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R L Stouffer

Publications and source records attributed to R L Stouffer.

At least 19 recordsLinked to original sources
PubMed1992

Inhibin production by macaque granulosa cells from pre- and periovulatory follicles: regulation by gonadotropins and prostaglandin E2.

Although inhibin (IN) is secreted by granulosa cells (GC) of preovulatory follicles, the major source of immunoreactive IN circulating during the primate ovarian cycle is the corpus luteum. The aims of this study were (1) to investigate culture conditions for optimal IN production by luteinized GC (LGC) from rhesus monkeys and (2) to compare IN and progesterone (P) production by nonluteinized GC (NGC) and LGC in response to putative agonists. Animals were treated for up to 9 days with human menopausal gonadotropins to promote the development of multiple preovulatory follicles. GC were obtained from large follicles before (NGC) or 27 h after (LGC) an ovulatory injection of hCG. For Aim 1, cells were cultured in Hams F-10 medium +/- hCG (100 ng/ml) with or without the addition of insulin/transferrin/selenium, 10% fetal bovine serum, or 10% Serum-Plus (JRH Biosciences, Lenexa, KS). Medium was changed on Days 1, 2, 4, 6, and 8, and IN and P concentrations were determined by RIA. Basal (unstimulated) IN production by LGC was enhanced and maintained for 6-8 days in the presence of serum, but rapidly declined in the absence of serum. In contrast, basal P secretion declined regardless of exposure to serum. Human CG consistently increased (p less than 0.05) IN production only in the presence of serum but stimulated (p less than 0.05) P production under all conditions. For Aim 2, cells were cultured for 4 days in Ham's F-10 medium + 10% macaque serum +/- hCG (100 ng/ml), hFSH (100 ng/ml), prostaglandin E2(PGE2; 14 microns), or dibutyryl(db)-cAMP (5 mM).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

The Sulawesi Crested Black Macaque (Macaca nigra) menstrual cycle: changes in perineal tumescence and serum estradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone levels.

Events in the normal menstrual cycle of the endangered Sulawesi Crested Black Macaque (Macaca nigra) were characterized. Daily blood samples were obtained during 10 menstrual cycles from five M. nigra demonstrating regular cycles. The amount of perineal tumescence was scored daily. Serum levels of estradiol and progesterone were determined by RIA, serum LH levels were determined by the mouse Leydig cell bioassay, and serum FSH levels were determined by the rat granulosa cell aromatase bioassay. Cycle length was 39.8 +/- 1.0 days (mean +/- SEM) with an LH surge occurring 25 +/- 1.5 days from the onset of menses. After menses, both LH and estradiol were initially depressed, with estradiol first exceeding 50 pg/ml 8 days before the LH surge. In five cycles, peak estradiol levels (340 +/- 44 pg/ml) occurred on the day of the LH surge (637 +/- 58 ng/ml) and in the other five cycles, on the day before the LH surge. There was a broad increase of FSH in midcycle without a well-defined surge corresponding to the LH surge. Progesterone began increasing on the day of the LH surge and reached peak levels (6.8 +/- 0.96 ng/ml) 8 days later. Maximal perineal tumescence was generally associated with the time of the LH surge, but variation between animals made it impossible to predict accurately the day of the LH surge by perineal tumescence scores alone.

Animals↗
PubMed1992

Gonadotropin surge increases fluorescent-tagged low-density lipoprotein uptake by macaque granulosa cells from preovulatory follicles.

In the primate ovary, luteal steroidogenesis is largely dependent upon cholesterol derived from receptor-mediated uptake of circulating low-density lipoprotein (LDL). However, granulosa cells (GC) of preovulatory follicles possess few LDL binding sites compared to those present in developing and mature corpora lutea. We recently reported (Endocrinology 1991; 129:3247-3253) that uptake of LDL tagged with the fluorescent probe 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanine perchlorate (DiI) can be monitored in macaque luteal cells by fluorescence-activated flow cytometry. This study was designed to determine whether an ovulatory stimulus induced uptake of DiI-LDL in GC aspirated from preovulatory follicles of macaques undergoing ovarian stimulation. Development of multiple large follicles was stimulated in adult rhesus macaques with human gonadotropin treatment for 9 days. On Day 10, monkeys received either no ovulatory stimulus or 1000 IU hCG to initiate ovulatory events. GC were aspirated on Day 10 in monkeys receiving no ovulatory stimulus (nonluteinized GC) or 27 h or 34 h after hCG injection (luteinizing GC). GC were resuspended in Ham's F-10 medium + 0.1% BSA and incubated with several concentrations (0-25 micrograms/ml) of DiI-LDL (Biomedical Technologies, Stoughton, MA) for various time intervals (2-60 min). DiI-LDL uptake by GC was time- and concentration-dependent. Coincubation of cells with DiI-LDL and unlabeled LDL dose-dependently suppressed the percentage of fluorescent cells. In contrast, coincubation with up to a 250-fold excess of acetylated LDL or high-density lipoprotein did not alter the percentage of fluorescent GC.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Administration of human luteinizing hormone (hLH) to macaques after follicular development: further titration of LH surge requirements for ovulatory changes in primate follicles.

After stimulation of multiple follicular development, endogenous LH surges elicited by GnRH or GnRH agonist were of insufficient duration (4-14 h) to evoke oocyte maturation and luteinization in this species. In this study, periovulatory LH surge requirements were further titrated using hLH as the ovulatory stimulus. Beginning at menses, rhesus monkeys were treated with human gonadotropins for 9 days to stimulate follicular growth. To induce ovulatory maturation on day 10, animals received: 1) hCG (1000 IU, im; n = 8); 2) highly-purified, urinary hLH (2542 IU, im; n = 4); or 3) hLH (2542 IU, im) followed by three injections of hLH (200 IU, im) at 8-h intervals (0800, 1600, 2400 h) daily during the luteal phase until menses (n = 3). Oocytes and luteinizing granulosa cells were obtained via follicle aspiration 27 h after the initial hLH or hCG injection. Estradiol and progesterone levels were measured in daily serum samples by RIA. Bioactive LH levels were determined at selected intervals within 36 h of the hLH ovulatory stimulus. Nuclear maturity of oocytes was evaluated as an indicator for reinitiation of meiosis. Luteinizing granulosa cells were processed for indirect immunocytochemistry using a monoclonal antibody to human progesterone receptor. In vitro progesterone production by luteinizing granulosa cells over 24 h was also assessed in the absence and presence of hCG. In all groups, serum estradiol rose to similar peak levels on day 10. After hLH, bioactive LH levels peaked (1262 +/- 79 ng/mL; mean +/- SEM) by 2-6 h, declined thereafter but remained above surge levels (100 ng/mL) for 18-24 h. Within 24 h of hLH injection, serum progesterone increased to 13 +/- 3 nmol/L, but returned to baseline in 1-6 days. In contrast, higher levels of progesterone were observed after hCG (114 +/- 51 nmol/L) and during luteal phase treatment with hLH (137 +/- 25 nmol/L) and the luteal phase was longer (11.5 +/- 0.4 and 14.3 +/- 0.7 days, respectively). Of the total cohort of oocytes aspirated, the proportion of oocytes resuming meiotic maturation (metaphase I plus metaphase II) was similar after hCG (76%) and hLH (74%). However, the proportion of oocytes maturing to metaphase II tended to be less (P = 0.08) after hLH (13%) than hCG (22%). Fertilization rates were similar between the two groups. Progesterone receptor was detected in nuclei of luteinizing granulosa cells from all animals receiving hCG, but only in some given hLH.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

Activin-A inhibits progesterone production by macaque luteal cells in culture.

Since inhibin is produced during the luteal phase of the menstrual cycle in women and nonhuman primates, the primate corpus luteum (CL) may be a local site of inhibin/activin action. This study was designed to determine whether inhibin or activin altered steroidogenesis by macaque luteal cells in vitro. Luteal cells were obtained by enzymatic dispersion of CL from rhesus monkeys at midluteal phase of the menstrual cycle. Cells (2 x 10(4)/0.2 mL) were cultured in wells coated with extracellular matrix from bovine corneal endothelial cells in Dulbecco's modified Eagle's medium/F-12 medium (1:1 vol/vol) + insulin (2 ng/mL), transferrin (5 ng/mL), H2SeO3 (0.25 nmol), and aprotinin (10 micrograms/mL). Various concentrations (0-400 ng/mL) of recombinant human-inhibin-A, recombinant human-activin-A or human CG (hCG) (100 ng/mL; CR123) alone or in combination with inhibin or activin were added to the culture media (n = 5 Exp). Media were changed daily for 4 days and progesterone (P) concentrations were determined by RIA. Inhibin exposure did not alter P levels compared to that of control (untreated) cultures. In contrast, activin (10-400 ng/mL) suppressed P production (P less than 0.05) below controls and inhibin-treated cultures by days 3 and 4. Exposure to hCG increased P levels throughout culture (9 x control levels by day 4; P less than 0.05). hCG-stimulated P production was unaltered by inhibin, whereas activin (50-400 ng/mL) reduced (maximal inhibition of 40%; P less than 0.05) hCG-stimulated P production by day 4 of culture. Cell number on day 4 was not altered by any dose of inhibin or activin, but the number of cells staining for 3 beta-hydroxysteroid dehydrogenase was reduced (P less than 0.05) by 32.9 +/- 2.6% in activin-treated cultures. Since P levels declined during culture in all treatment groups, in a second series of experiments (n = 4), luteal cells were cultured for 4 days with or without hCG (100 ng/mL) and low density lipoprotein (LDL; 100 micrograms/mL) +/- 0-400 ng activin/mL. P production in the presence of hCG+LDL was greatly enhanced compared to other treatment groups and was sustained during days 2-4 of culture. Activin at doses of 50-400 ng/mL suppressed (maximal inhibition of approximately 35%; P less than 0.05) hCG+LDL-stimulated P production on days 3 and 4. These results suggest that the primate CL is a target for activin action to suppress luteal cell activities, including gonadotropin-regulated, lipoprotein-mediated steroidogenesis.

3-Hydroxysteroid Dehydrogenases↗
PubMed1991

Progesterone production by monkey luteal cell subpopulations at different stages of the menstrual cycle: changes in agonist responsiveness.

Small (less than or equal to 15 microns diameter) and large (greater than 20 microns diam.) luteal cells of the rhesus monkey have been separated by flow cytometry based on light scatter properties. To determine whether the steroidogenic ability and agonist responsiveness of luteal cell subpopulations vary during the life span of the corpus luteum, small and large cells were obtained at early (Days 3-5), mid (Days 7-8), mid-late (Days 11-12), and late (Days 14-15) luteal phase of the cycle. Cells (n = 4 exp./group) were incubated in Ham's F-10 medium + 0.1% BSA for 3 h at 37 degrees C with or without hCG (100 ng/ml), prostaglandin E2 (PGE2; 14 microM), dibutyryl-cAMP (db-cAMP; 5 mM), or pregnenolone (1 microM). Basal progesterone (P) production by large cells was up to 30-fold that by small cells depending on the stage of the cycle. HCG stimulated (p less than 0.05) P secretion by both small (1.8 +/- 0.2-fold) and large (3.7 +/- 0.7-fold) cells in the early luteal phase. HCG responsiveness declined during the luteal lifespan; P production by small cells was not significantly enhanced by hCG by mid luteal phase, whereas that by large cells was stimulated 1.7 +/- 0.2-fold (p less than 0.05) even at late luteal phase. Cell responses to db-cAMP were similar to those for hCG.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Localization of androgen receptor in the follicle and corpus luteum of the primate ovary during the menstrual cycle.

Ovarian androgens may act locally to modulate follicular and luteal function in various species. This study examined the distribution of androgen receptors within the primate ovary throughout the menstrual cycle. Ovaries were collected from rhesus and cynomolgus monkeys during the early, mid-, and late (n = 3-5 per stage) follicular and luteal phases of the cycle. The tissues were processed for indirect immunocytochemical localization of androgen receptors with a specific monoclonal antibody against human androgen receptor (AN1-15). In addition, ovaries (n = 3) were collected from rhesus monkeys for biochemical detection of androgen receptor using 3H-androgen and AN1-15. Specific immunocytochemical staining, as determined by comparing adjacent tissue sections incubated with either AN1-15 or a nonspecific control antibody, was exclusively nuclear. Androgen receptor was detected in the germinal epithelium and ovarian stroma at all stages of the cycle. The thecal and granulosa cells of growing follicles, and of many but not all atretic follicles, contained androgen receptors. Luteinizing granulosa cells of the periovulatory follicle and luteal cells from the early and midluteal phase stained intensely for androgen receptor. Regressing corpora lutea of the late luteal phase also stained for androgen receptor; however, fully regressed corpora lutea in the early follicular phase of the next cycle did not exhibit receptor staining. Luteal cells that were androgen receptor-positive also stained histochemically for the presence of 3 beta-hydroxysteroid dehydrogenase. Sucrose gradient analysis with radiolabeled androgen demonstrated a shift in the androgen receptor peak in monkey ovarian tissue upon addition of AN1-15, confirming the presence of androgen receptor.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Comparison of the steroidogenic response of luteinized granulosa cells from rhesus monkeys to luteinizing hormone and chorionic gonadotropin.

The dynamics of the steroidogenic response of nonprimate gonadal cells to gonadotropins suggests that the biologic action of pituitary LH differs from that of placental CG. To compare the response to LH and CG in primate species, luteinized granulosa cells (LGCs) obtained from rhesus monkeys following follicle stimulation were cultured in vitro. The pattern and levels of progesterone (P) produced during culture was influenced by the concentration (0-10%) and type (fetal bovine or macaque) of serum in the medium and whether LGCs were plated on plastic or extracellular matrix from bovine corneal endothelial cells. After 2-3 days of culture, LGCs were exposed acutely (15-30 min) or chronically (6 h) to 1 or 100 ng/ml human LH (hLH, NIH 1-2) or hCG (CR123), 50 micrograms/ml ovine LH (oLH, NIH-oLH-25), or incubated in the absence of gonadotropins (controls). After the first 15-30 min, the media were changed at 30-min intervals. Both acute and chronic exposure to hLH, hCG, and oLH increased (p less than 0.05) P concentrations above control levels within 15-30 min. There were no differences in the patterns or levels of P elicited by hLH or hCG over time for each treatment condition. Chronic exposure to 1 and 100 ng/ml hLH or hCG and 50 micrograms/ml oLH sustained P levels above that of controls for the 6-h interval. Acute exposure to 1 ng/ml hLH or hCG failed to maintain elevated P levels throughout the experiment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Current understanding of the corpus luteum in women and nonhuman primates.

Despite the important advances detailed in this review, our understanding of the factors and mechanisms controlling the function of the corpus luteum in the menstrual cycle is rudimentary. Luteolysis remains a mystery. As the activities and interactions between different cell types in the corpus luteum are defined and the role(s) of endocrine, paracrine, and autocrine factors are elucidated, however, we should begin to understand the "self-destruct" process at the end of the cycle. As cellular and molecular approaches combine with physiologic techniques, new information will be available to address the clinical issues of luteal dysfunction which perplex us all.

Animals↗
PubMed1991

Differential uptake of fluorescent-tagged low density lipoprotein by cells from the primate corpus luteum: isolation and characterization of subtypes of small and large luteal cells.

Three enriched populations of cells [C alpha, non-steroidogenic cells less than or equal to 15 microns in diameter; R1, small (less than or equal to 15 microns) steroidogenic cells; and R3, large (greater than 20 microns) steroidogenic cells] have been isolated from the macque corpus luteum using flow cytometry based on light scatter properties. To determine whether the cell populations differ in their ability to bind and internalize low-density lipoprotein (LDL), collagenase-dispersed cells were prepared from the corpus luteum of rhesus monkeys at midluteal phase of the menstrual cycle. Cells were incubated in Hams F-10 medium containing fluorescent-tagged LDL (DiI-LDL). Optimal labeling occurred at 10 micrograms DiI-LDL/10(6) cells.ml incubated for 20 min at 37 degrees C. Labeled cells were analyzed and sorted by flow cytometry based on light scatter and fluorescence. Only 8.2 +/- 1.0% (n = 10) of C alpha cells exhibited fluorescence intensity greater than the autofluorescence of unlabeled cells. In contrast, 52.3 +/- 3.4% of R1 cells and 83.9 +/- 2.3% of R3 cells were fluorescent. Uptake of DiI-LDL was competitively inhibited when cells were conincubated with either unlabeled monkey or human LDL, but human high-density lipoprotein and very low-density lipoprotein were less effective. Progesterone (P) production by fluorescent [DiI-LDL(+)] R1 luteal cells was increased (P less than 0.001) in the presence of pregnenolone, but not human (h) CG, consistent with earlier results for the R1 population. Surprisingly, basal P production by the nonfluorescent [DiI-LDL(-)] R1 cells was similar to that by fluorescent cells and was stimulated by both hCG (P less than 0.01) and pregnenolone (P less than 0.001). Basal P production by DiI-LDL(+) R3 cells was nearly 10-fold greater than that by DiI-LDL(-) R3 cells. P secretion by both DiI-LDL(+) and (-) R3 cells was stimulated by hCG (P less than 0.01) and pregnenolone (P less than 0.001). DiI-LDL(-) C alpha cells produced barely detectable levels of P, but DiI-LDL(+) C alpha cells secreted P at levels similar to R1 cells. We conclude that: 1) multiparameter (light scatter and fluorescence) cell sorting is a useful method for separating enriched populations of cells from the corpus luteum; and 2) small and large luteal cell populations from the macaque corpus luteum consist of subtypes of steroidogenic cells that differ in lipoprotein uptake and/or gonadotropin sensitivity.

Animals↗
PubMed1991

Titrating luteinizing hormone surge requirements for ovulatory changes in primate follicles. I. Oocyte maturation and corpus luteum function.

The amplitude and duration of the midcycle LH surge required for ovulatory maturation of the follicle and its enclosed oocyte in primates are unknown. To titrate periovulatory LH requirements, female rhesus monkeys received human gonadotropins (FSH with/without LH) for 9 days beginning at menses to promote the development of multiple preovulatory follicles. The next day, animals (n = 4-6/group) received: 1) no ovulatory stimulus; 2) 1000 IU hCG, im; 3) one injection of 100 micrograms GnRH, sc (GnRH-1); 4) three injections of GnRH (GnRH-3) at 3-h intervals (0800, 1100, and 1400 h); or 5) two injections of 50 micrograms GnRH agonist (GnRHa), sc, 8 h apart (0800 and 1700 h) to induce ovulatory maturation. Follicles were aspirated 27 h after the hCG or initial GnRH/GnRHa injection or on days 8 and 10 in animals receiving no ovulatory stimulus. Nuclear maturity of oocytes was evaluated as a marker for reinitiation of meiosis. Estradiol and progesterone levels were determined in daily serum samples by RIA. Levels of LH(-like) bioactivity were measured at selected intervals after hCG injection and within 24 h of GnRH/GnRHa treatment. In all groups, estradiol continuously rose to similar peak levels on day 10. The hCG treatment markedly elevated circulating LH-like bioactivity for up to 3 days. In GnRH-1, bioactive LH increased to 433.1 +/- 170.2 ng/mL (mean +/- SEM; n = 3) within 1-2 h, but then decreased to baseline (4.9 +/- 1.5 ng/mL) within 6 h. GnRH-3 and GnRHa treatment extended the interval of elevated bioactive LH to 8 and 14 h, respectively. There was no difference in the peak levels of LH(-like) bioactivity reached after hCG, GnRH, or GnRHa injection. Functional luteal phases were absent in monkeys receiving no ovulatory stimulus, whereas hCG treatment increased progesterone levels to 101 +/- 9 nmol/L (n = 6) and elicited functional luteal phases of 11.8 +/- 0.4 days. In contrast, only one animal in the GnRH/GnRHa groups (i.e. one GnRH-3 monkey) displayed elevated progesterone levels in the luteal phase. Of the total cohort of oocytes aspirated from follicles, a greater (P less than 0.05) proportion were classified as being in metaphase I or II of meiosis after hCG treatment (86%) compared to no ovulatory stimulus (13%), GnRH-1 (0%), GnRH-3 (43%), and GnRHa (12%). Thus, GnRH elicits a transient LH surge that can be extended by GnRH-3 or GnRHa in stimulated cycles of monkeys.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Titrating luteinizing hormone surge requirements for ovulatory changes in primate follicles. II. Progesterone receptor expression in luteinizing granulosa cells.

The events in granulosa cells that are initiated by the midcycle LH surge during luteinization of the primate follicle are poorly defined. This study was designed 1) to determine whether an ovulatory dose of hCG can induce progesterone receptors (PR) in macaque granulosa cells, and if so, 2) to begin titrating gonadotropin requirements for PR expression and progesterone production by luteinizing granulosa cells. Rhesus monkeys were treated with human FSH and LH for up to 9 days to stimulate the growth of multiple follicles. The next day, animals (n = 4-5/group) received: 1) no ovulatory stimulus; 2) 1000 IU hCG, im; 3) one injection of 100 micrograms GnRH, sc (GnRH-1); 4) three injections of GnRH (GnRH-3) at 3-h intervals (0800, 1100, and 1400 h); or 5) two injections of 50 micrograms GnRH agonist (GnRHa), sc, 8 h apart (0800 and 1700 h). Granulosa cells obtained by follicle aspiration 27 h after the hCG or initial GnRH/GnRHa injection or on days 8 or 10 from animals receiving no ovulatory stimulus were processed for indirect immunocytochemistry using a monoclonal antibody to human PR (JZB39). Specific staining for PR, determined by comparing cells incubated with PR antibody vs. a nonspecific antibody, was undetectable in granulosa cells from monkeys without an ovulatory stimulus. In contrast, the majority (64 +/- 5%) of cells from hCG-treated animals stained intensely for PR. In the GnRH/GnRHa groups, granulosa cells from only one animal (i.e. one GnRH-3 monkey) showed positive staining for PR. During 24-h culture in Ham's F-10 medium containing 10% monkey serum, basal progesterone production by cells from the hCG-treated group (2163 nmol/L.8 x 10(4) cells) was higher than that by cells from the no ovulatory stimulus/GnRH-1/GnRH-3/GnRHa groups (60, 111, 194, and 332 nmol/L, respectively). However, granulosa cells from the hCG-treated group were less responsive to hCG in vitro in terms of enhanced progesterone production (2 times control levels) than cells from the other four groups (up to 30 times control levels). This study provides direct evidence that an ovulatory dose of hCG induces PR expression in granulosa cells of luteinizing follicles during stimulated cycles in rhesus monkeys. However, repeated injections of GnRH/GnRHa that produced surge levels (greater than 100 ng/mL) of endogenous LH for up to 14 h failed to induce PR expression or progesterone production by granulosa cells. Thus, an extended LH surge more typical of that in the normal menstrual cycle (48-50 h) may be necessary for PR expression and luteinization of granulosa cells in primate follicles.

Animals↗
PubMed1990

Maturity at collection and the developmental potential of rhesus monkey oocytes.

The purpose of this study was to evaluate the in vitro fertilizability of rhesus monkey oocytes and the developmental capacity of the resulting embryos as they relate to oocyte maturation at the time of follicular aspiration. Animals were hyperstimulated with human follicle-stimulating hormone (hFSH) and human luteinizing hormone (hLH), with follicular aspiration performed 27 h after administration of an ovulatory stimulus (1000 IU human chorionic gonadotropin [hCG] or 3 x 100 micrograms gonadotropin-releasing hormone [GnRH]). In 7 animals exhibiting a continuously rising pattern of serum estradiol through Day 10 of hyperstimulation, 45 germinal vesicle-intact (GV), 106 metaphase I (MI), and 24 metaphase II (MII) oocytes were collected and cultured in vitro. Upon reaching MII, oocytes were inseminated with 5 x 10(4) motile sperm/ml. Twenty-four percent of GV oocytes cultured in vitro matured to MII with 11 inseminated and none fertilized. Seventy-three percent of MI oocytes matured to MII in vitro with 50% inseminated and 32% fertilized. Oocytes collected at MII stage and inseminated underwent fertilization at a high rate of efficiency (93%). Pronuclear to 8-cell stage embryos were frozen and, upon thawing, 67% (10/15) survived with all blastomeres intact. Frozen-thawed embryos (2- to 6-cell) were transferred to the oviducts of 4 recipients (2 embryos/recipient) during the early luteal phase (1-3 days post LH surge) of natural menstrual cycles. Three twin pregnancies resulted. Thus, a positive correlation exists between the degree of nuclear maturation of rhesus monkey oocytes at collection and their potential for fertilization in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Intraluteal infusions of prostaglandins of the E, D, I, and A series prevent PGF2 alpha-induced, but not spontaneous, luteal regression in rhesus monkeys.

A luteotropic role for prostaglandins (PGs) during the luteal phase of the menstrual cycle of rhesus monkeys was suggested by the observation that intraluteal infusion of a PG synthesis inhibitor caused premature luteolysis. This study was designed to identify PGs that promote luteal function in primates. First, the effects of various PGs on progesterone (P) production by macaque luteal cells were examined in vitro. Collagenase-dispersed luteal cells from midluteal phase of the menstrual cycle (Day 6-7 after the estimated surge of LH, n = 3) were incubated with 0-5,000 ng/ml PGE2, PGD, 6 beta PGI1 (a stable analogue of PGI2), PGA2, or PGF2 alpha alone or with hCG (100 ng/ml). PGE2, PGD2, and 6 beta PGI1 alone stimulated (p less than 0.05) P production to a similar extent (2- to 3-fold over basal) as hCG alone, whereas PGA2 and PGF2 alpha alone had no effect on P production. Stimulation (p less than 0.05) of P synthesis by PGE2, PGD2, and 6 beta PGI1 in combination with hCG was similar to that of hCG alone. Whereas PGA2 inhibited gonadotropin-induced P production (p less than 0.05), that in the presence of PGF2 alpha plus hCG tended (p = 0.05) to remain elevated. Second, the effects of various PGs on P production during chronic infusion into the CL were studied in vivo. Saline with or without 0.1% BSA (n = 12), PGE2 (300 ng/h; n = 4), PGD2 (300 ng/h; n = 4), 6 beta PGI1 (500 ng/h; n = 3), PGA2 (300 ng/h; n = 4), or PGF2 alpha (10 ng/h; n = 8) was infused via osmotic minipump beginning at midluteal phase (Days 5-8 after the estimated LH surge) until menses. In addition, the same dose of PGE, PGD, PGI, or PGA was infused in combination with PGF2 alpha (n = 3-4/group) for 7 days. P levels over 5 days preceding treatment were not different among groups. In 5 of 8 monkeys receiving PGF2 alpha alone, P declined to less than 0.5 ng/ml within 72 h after initiation of infusion and was lower (p less than 0.05) than controls. The length of the luteal phase in PGF2 alpha-infused monkeys was shortened (12.3 +/- 0.9 days; mean +/- SEM, n = 8; p less than 0.05) compared to controls (15.8 +/- 0.5). Intraluteal infusion of PGE, PGD, PGI, or PGA alone did not affect patterns of circulating P or luteal phase length.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1990

Disparate effects of the prostaglandin synthesis inhibitors, meclofenamate, and flurbiprofen on monkey luteal tissue in vitro.

Intraluteal infusion of the prostaglandin (PG) synthesis inhibitor, sodium meclofenamate (Mec) causes premature luteolysis in rhesus monkeys. To evaluate further the actions of PG synthesis inhibitors in primate luteal function, we examined the in vitro effects of Mec and another inhibitor, flurbiprofen (Flur), on PG, cAMP, and progesterone (P) production by macaque luteal tissue obtained at midluteal phase of the menstrual cycle. First, collagenase dispersed luteal cells were incubated with 0-100 microM Mec or Flur, either alone or in the presence of 10 microM arachidonic acid (AA) to assess PGF2 alpha and PGE2 synthesis. Levels of both PGF2 alpha and PGE2 were stimulated (P less than 0.05) by AA (3.3- and 5.8-fold, respectively). Maximal suppression (P less than 0.01) of basal and AA-stimulated PGF2 alpha and PGE2 synthesis was elicited by 1 microM Mec and Flur. Second, adenylate cyclase activity, measured by the conversion of alpha 32P-ATP to alpha 32P-cAMP, was monitored in luteal homogenates exposed to increasing doses of Mec and Flur either alone or with maximal stimulatory doses of hCG, PGE2, or PGI2. Mec elicited a dose-dependent reduction (P less than 0.01) in control activity (incubated with 50 microM GTP), as well as inhibiting hCG- and PG-stimulated activity. The presence of 100 microM Mec suppressed (P less than 0.01) hCG-, PGE2- and PGI2-stimulated activity to control levels, but had no effect on activity stimulated by GMP-P(NH)P or forskolin. In contrast, Flur at any dose did not alter control activity or that stimulated by hormonal or nonhormonal activators. Third, P production by dispersed luteal cells was quantified during exposure to 0, 1, and 100 microM Mec or Flur alone or with maximal stimulatory doses of hCG, PGE2, PGD2, 6 beta PGI1, PGA2, or dibutyryl cAMP (dbcAMP). All hormones and dbcAMP stimulated (P less than 0.01) P synthesis 2-3 fold over basal levels, except PGA2, which had no effect. The presence of 100 microM Mec reduced (P less than 0.01) basal P production by 62% and abolished (P less than 0.05) hCG-, PG-, and dbcAMP-induced stimulation. Conversely, neither 1 microM Mec nor either dose of Flur affected P synthesis in the absence or presence of hormones or dbcAMP. These data indicate that: 1) Mec and Flur are potent inhibitors of PG synthesis in primate luteal cells in vitro and 2) higher doses of Mec suppress PG- and gonadotropin-sensitive adenylate cyclase activity and P production.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenylyl Cyclases↗
PubMed1990

The effect of intraluteal infusion of deglycosylated human chorionic gonadotropin on the corpus luteum in rhesus monkeys.

Removal of the carbohydrates from hCG results in an antagonist (degly-hCG) that competitively inhibits hCG/LH-stimulated adenylate cyclase in macaque luteal tissue in vitro, but its effect in vivo is controversial. To examine the effect of degly-hCG on the lifespan and steroidogenic activity of the primate corpus luteum, the antagonist was administered to female rhesus monkeys (n = 7) beginning at the midluteal phase of the menstrual cycle. In a control cycle the saline vehicle was infused via an osmotic minipump directly into the corpus luteum. In a subsequent cycle, one of three dose rates of degly-hCG (0.001, 0.009, and 0.09 nmol/h) was infused into the corpus luteum. Pump implantation and infusion began 5-9 days after the midcycle LH surge and continued for 7 days. Peripheral venous blood was collected daily from day 8 of the cycle until menses, and serum progesterone levels were determined by RIA. Progesterone levels and patterns were similar in animals that received either the saline vehicle or degly-hCG, and the length of the luteal phase in monkeys receiving any dose of degly-hCG (16.4 +/- 0.5 days) was not different from that in animals receiving a control infusion (16.1 +/- 0.9 days). In a corollary study, an intraluteal infusion of degly-hCG (0.009 nmol/h) in the midluteal phase did not prevent stimulation of progesterone levels after im injection of hCG (15 IU/day for 5 days). We conclude that whereas degly-hCG is a useful tool to examine gonadotropin action in vitro, it is not a potent gonadotropin antagonist in vivo.

Adenylyl Cyclases↗