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Biomedical subjects

D T Baird

Publications and source records attributed to D T Baird.

At least 145 records · Page 8Linked to original sources
PubMed1992

Medical abortion in women of less than or equal to 56 days amenorrhoea: a comparison between gemeprost (a PGE1 analogue) alone and mifepristone and gemeprost.

OBJECTIVE: To determine the efficacy of a new dose regimen of vaginal gemeprost (1 mg every 6 h up to three doses) in induction of abortion in women less than or equal to 56 days gestation, and to compare this regimen with mifepristone (200-600 mg) followed 48 h later by a single dose of gemeprost (1 mg). DESIGN: Two separate protocols, with 50% of the subjects randomized to one or other protocol. SETTING: The Royal Infirmary of Edinburgh, Scotland, UK. SUBJECTS: 301 referred by their general practitioner or local family planning clinic, requesting termination of pregnancy at less than or equal to 56 days amenorrhoea. INTERVENTIONS: Ongoing pregnancies and incomplete abortions were terminated surgically. MAIN OUTCOME MEASURES: Number of complete abortions, analgesic requirements and bleeding pattern following treatment. RESULTS: Complete abortion occurred in 87% of women treated with gemeprost alone and 98% of women treated with mifepristone and gemeprost (P = 0.0004). Analgesic requirements were greater in the group treated with gemeprost alone, compared with the group treated with mifepristone and gemeprost (P = 0.0001). CONCLUSION: The new dose regimen of gemeprost can be used for early induced abortion, but the use of mifepristone and gemeprost has several advantages over the use of gemeprost alone.

Abortifacient Agents, Nonsteroidal↗
PubMed1992

Hormonal regulation of the growth and steroidogenic function of human granulosa cells.

The aim of this study was to assess development-related interactions between gonadotropins and insulin-like growth factor (IGF-I) on DNA synthesis and steroidogenesis in human granulosa cells. "Immature" granulosa cells were obtained from follicles during the late luteal phase or first half of the follicular phase; "mature" granulosa cells came from follicles during the second half of the follicular phase but before the midcycle LH surge; and granulosa-lutein cells were obtained as a by-product of in vitro fertilization. Granulosa cells were cultured for 96 h in serum-free medium 199 with and without LH or FSH, and in the presence and absence of IGF-I. The cell monolayers were then incubated with [3H]methyl thymidine to assess DNA synthesis. Spent culture medium was assayed for progesterone and estradiol content. Immature granulosa cells: Tritiated thymidine uptake in granulosa cell cultures from immature follicles were significantly increased by IGF-I. FSH was able to maintain or increase basal and IGF-I stimulated growth whereas LH had no effect. Basal progesterone production was low and not increased by either FSH or LH. However, treatment with FSH, but not LH, increased aromatase activity. Mature granulosa cells: IGF-I also stimulated thymidine uptake. However, whereas FSH either maintained or increased thymidine uptake by these cells, LH dose dependently suppressed thymidine uptake. This inhibitory action of LH was accentuated by the presence of IGF-I. Despite the inhibitory effect of LH on thymidine uptake, the gonadotropin markedly stimulated steroid production and the maximal steroidogenic response to LH was equivalent to 3-fold greater than that to FSH. Granulosa-lutein cells: Patterns of basal and IGF-I- and gonadotropin-stimulated steroid synthesis were similar to those observed for mature granulosa cells but steroid production rates were higher. Suppression of basal and IGF-I-stimulated thymidine uptake by LH was even more pronounced. These results suggest that the granulosa cell LH receptor, once expressed, negatively regulates cell growth and, simultaneously, positively regulates steroid synthesis. This development related event could be crucial to the mechanism whereby granulosa cells cease to divide and commence maximal rates of steroid synthesis in response to the LH surge.

Adult↗
PubMed1992

Hormone production in vivo and in vitro from follicles at different stages of the oestrous cycle in the sheep.

This experiment was undertaken in order to investigate the production of inhibin, oestradiol and androstenedione by ovarian follicles at different stages of the oestrous cycle in sheep. Twenty-four Scottish Blackface ewes were allocated to four groups of six ewes, i.e. those operated on during the luteal phase (day 10), and those operated on during the follicular phase 24-30, 36 and 60 h after the induction of luteal regression by an injection of 125 micrograms cloprostenol on day 10 of the luteal phase. Samples of jugular and ovarian venous blood were collected under anaesthesia and ovaries were then removed and all follicles larger than 3 mm diameter dissected out and incubated in medium for 2 h. After injection of cloprostenol, luteal regression occurred as indicated by a fall in the secretion rate of progesterone. The ovarian secretion rate of inhibin was similar at all stages of the follicular phase and during the luteal phase while, in contrast, the secretion rate of oestradiol was significantly (P less than 0.05) elevated in the group 24 h after injection of cloprostenol. There was good correlation between the in-vivo ovarian secretion rate and production rate during incubation in vitro for both inhibin (r = 0.57) and oestradiol (r = 0.60). When follicle diameter was compared with in-vitro hormone production there was good correlation for inhibin (r = 0.72) with larger follicles producing more inhibin, while the value for oestradiol was somewhat lower (r = 0.57) owing to the presence of large atretic follicles with low oestradiol production. Androstenedione production showed a lower correlation with follicle diameter (r = 0.39). When the four time periods were compared separately, there were significantly (P less than 0.05) more follicles with high in-vitro oestradiol production (greater than 90 fmol/min) in the group at 36 h than in the other three groups, while inhibin release in relation to follicle size was similar in the four groups. Large oestrogenic follicles were responsible for 90% of the total oestradiol production during culture while only providing 55% of the total inhibin production, with large non-oestrogenic and small follicles contributing 33% and 12% of inhibin production respectively. From the results of this study we conclude that while oestradiol is mainly produced by the large oestrogenic follicles, a considerable amount of inhibin is also produced by large non-oestrogenic and small follicles.(ABSTRACT TRUNCATED AT 400 WORDS)

Androstenedione↗
PubMed1992

The role of inhibin and oestradiol in the control of FSH secretion in the sheep.

The relative importance of inhibin and oestradiol in the control of FSH and LH secretion in the ewe was investigated by passive immunization in intact animals and by hormone replacement therapy following acute ovariectomy, in the same experiment. Mature Scottish Blackface ewes on day 10 of the luteal phase were allocated to nine groups of four to five animals. Four groups were ovariectomized and immediately treated with either progesterone alone or in combination with steroid-stripped ovine follicular fluid ('inhibin') and/or oestradiol. Three further groups of ewes were left intact and injected with antibodies to the 1-26 alpha peptide fragment of porcine inhibin and/or oestradiol-17 beta. Two groups of animals were either ovariectomized alone with no further treatment, or were left intact and treated with normal sheep plasma to act as controls. Blood samples were collected at 2 h intervals from 12 h before until 48 h after ovariectomy/immunization, and from 12 to 24 h after treatment, blood samples were collected at 10-min intervals. After ovariectomy there was a large rise in the peripheral concentration of LH (P less than 0.001) which was not affected by treatment with progesterone alone but was completely prevented by treatment with progesterone and oestradiol. Treatment with inhibin had no effect on this post-castrational rise in LH. In intact ewes, immunization against oestradiol, alone or in combination with inhibin, resulted in a rise in the concentration of LH, while immunization against inhibin had no effect on LH concentration. The peripheral concentration of FSH showed a significant (P less than 0.001) increase after ovariectomy which was not affected by treatment with progesterone alone. Treatment with inhibin or oestradiol alone caused a significant (P less than 0.01) reduction in this rise, while treatment with inhibin and oestradiol together completely prevented this post-castrational rise in FSH concentration. Passive immunization against inhibin or oestradiol alone resulted in a transitory (P less than 0.01) rise in the peripheral concentration of FSH, while immunization against the two hormones in combination resulted in a significantly (P less than 0.01) larger rise. During the 14-h period after treatment, the rise in the concentration of FSH in this combined immunization group was not significantly different from that seen in the control ovariectomized group. These results provide evidence that FSH secretion is under the control of both oestradiol and inhibin, while reinforcing the hypothesis that inhibin is not involved in the regulation of LH production, which is under the dual control of oestradiol and progesterone.

Animals↗
PubMed1992

An open study comparing two regimens of gemeprost for the termination of pregnancy in the second trimester.

Two regimens of the prostaglandin E1 analogue, gemeprost, were compared in an open trial for termination of pregnancy between 12 and 18 weeks. Fifty women received 5 x 1 mg of gemeprost every 3 h and in another 50 cases, 4 x 1 mg of gemeprost was administered every 6 h. Although the median abortion interval was slightly shorter in the 3-hourly group (15.9 h vs. 16.9 h; p = 0.5), the cumulative abortion rates at 24 h were similar (88% vs. 82%; p less than 0.5). In women who aborted within the first 24 h, significantly fewer pessaries (p less than 0.01) were required to induce abortion in the 6-h treatment group (median 3, range 1-4) than the 3-h group (median 5, 2-5). Parous women in both treatment groups required fewer pessaries to induce abortion than did nulliparous women (not significant; p = 0.5). Significantly (p less than 0.01) fewer pessaries were required to induce abortion in the 6-h gemeprost group. The were no significant differences between the groups regarding incidences of diarrhea, vomiting, or the request for analgesia. These results suggest that in many women the number of pessaries used to induce mid-trimester abortion could be reduced by lengthening the interval between insertion of pessaries within the first 24 h, without loss of clinical efficacy.

Abortifacient Agents, Nonsteroidal↗
PubMed1992

Molecular basis of gonadotrophin action on human granulosa cell function.

We studied in vitro the effects of Follicle Stimulating Hormone (FSH) and Luteinising Hormone (LH) on: 1) mature human granulosa cell proliferation and steroidogenesis; 2) intra-cellular second messenger (cAMP) generation, and the effects of cAMP analogues on cell function; and 3) mRNA expression of the rate limiting enzymes for progesterone and oestradiol synthesis namely: Cholesterol side chain cleavage (P450 SCC), Aromatase (P450 Arom); and 4) LH receptor mRNA expression. FSH maintained or stimulated, whereas LH markedly inhibited, basal granulosa cell proliferation. Steroidogenesis (oestradiol and progesterone production) was dose dependently increased by both gonadotrophins; with LH having the greater effect. However, only LH was able to induce maximal progesterone production. FSH generated about ten fold less cAMP than LH; and low and high doses of cAMP analogue were able to mimic FSH and LH effects respectively. Northern analyses showed that both FSH and LH were able to induce maximal P450 Arom mRNA expression, whereas only LH could stimulate maximal P450 SCC mRNA transcription. Maximal P450 Arom mRNA expression was associated with less cAMP generation than for P450 SCC. LH-R mRNA expression was induced by FSH but the strongest stimulatory effect was with LH. These results indicate that: 1) FSH and LH have markedly different effects on mature granulosa cell function; 2) the differential action of FSH and LH are dose dependently mediated through intracellular cAMP; 3) mRNA expression of P450 SCC and P450 Arom are differentially regulated by gonadotrophins and intracellular cAMP; and 4) LH was the most potent inducer of its own receptor mRNA.(ABSTRACT TRUNCATED AT 250 WORDS)

Cyclic AMP↗
PubMed1991

Uterine contractility and induction of abortion in early pregnancy by misoprostol and mifepristone.

A combination of the antiprogestagen mifepristone and an exogenous prostaglandin given by intramuscular injection or intravaginal pessary is a highly effective means of inducing abortion in early pregnancy. However, the search for a stable oral prostaglandin preparation has been largely unsuccessful. The effect of misoprostol, an orally active prostaglandin used to treat peptic ulcer, on uterine contractility was investigated in 33 women in early pregnancy (under 56 days' amenorrhoea). After administration of misoprostol in doses ranging from 200 micrograms to 600 micrograms, there was a significant increase in uterine pressure. In a second group of women who were given 200-1000 micrograms misoprostol 48 h after the administration of 200 mg mifepristone, there was a significant increase in the amplitude and frequency of uterine contractions. Complete abortion took place in 18 of the 21 women who received misoprostol after mifepristone, but in only 2 of 40 women given misoprostol alone. Our findings show that misoprostol increases uterine activity in early pregnancy and suggest that, in combination with mifepristone, it may be a highly effective method of inducing therapeutic abortion.

Abortion, Therapeutic↗
PubMed1991

Effects of mifepristone in vivo on decidual prostaglandin synthesis and metabolism.

Mifepristone is an effective abortifacient in combination with an exogenous prostaglandin but its mechanism of action is unknown. Mifepristone stimulates prostaglandin production from decidua in tissue culture. To determine whether this effect also operates in vivo, we treated women with mifepristone 24, 36 and 48 hours prior to surgical termination. Decidua was removed at operation and the ability of the tissue to generate prostaglandin in culture subsequently assessed. Pretreatment with mifepristone 36 hours prior to termination of pregnancy resulted in an increased production of PGF2 alpha in tissue culture (p less than 0.01). A significant decrease in PGFM production was seen 24 hours after pretreatment with mifepristone in vivo (p less than 0.01). These results suggest that the increased uterine activity observed after administration of mifepristone may be due to stimulation of endogenous prostaglandin production and inhibition of prostaglandin metabolism.

Culture Techniques↗
PubMed1991

Effect of recombinant inhibin on androgen synthesis in cultured human thecal cells.

Effects of inhibin (recombinant human inhibin-A) on ovarian androgen synthesis were tested in vitro using serum-free monolayer cultures of human thecal cells. Treatment for 4 days with inhibin alone at doses between 10 and 100 ng/ml caused modest (approximately 2-fold) increases in production of androgen (androstenedione and dehydroepiandrosterone): similar to the maximal level of stimulation caused by luteinizing hormone (LH) (10 ng/ml) alone but only about one-third of that caused by insulin-like growth factor I (IGF-I) (30 ng/ml) alone. Combined treatment with LH and inhibin elicited additive effects on androgen production whereas LH and IGF-I were synergistic, giving rise to androgen production rates at least 40 times greater than control. Additional presence of inhibin caused up to 10-fold augmentation of the response to LH + IGF-I. Activin (recombinant human activin-A) was previously shown to inhibit LH + IGF-I-induced androgen synthesis in this human thecal cell culture system. In the present study we found that the additional presence of inhibin (greater than 1 ng/ml) completely neutralized this inhibitory action of activin (10 ng/ml). These effects of inhibin were dose-dependent (ED50 1-10 ng/ml) and maximal at approximately 100 ng/ml. Inhibin stimulation of androgen synthesis occurred in the absence of measurable effects on progesterone production, and cell numbers in cultured cell monolayers were unaltered by the protein. It is concluded that inhibin exerts potent and selective stimulation of human thecal cell androgen synthesis in vitro. These results a paracrine role for inhibin(s) in modulating follicular androgen biosynthesis in the human ovary.

Activins↗
PubMed1991

Cytogenetic analysis of unfertilized human oocytes.

Cytogenetic studies were carried out on 180 oocytes that appeared unfertilized after in-vitro fertilization. The majority of the 135 that were informative had grossly haploid second meiotic metaphases, two were grossly diploid, and five had a variety of different abnormalities. Twenty-one oocytes were abnormally fertilized and included prematurely condensed sperm chromosomes. The frequency of this phenomenon varied according to the stimulation protocol, those oocytes maturing longer in vivo showing less propensity to abnormal fertilizations. Thirteen per cent of the analysable haploid metaphases were hyperhaploid but none contained extra whole chromosomes. The extra components were a single chromatid (one case), or two single chromatids replacing a whole chromosome (four cases). The data suggest that the chromatids arose as a result of premature centromere division at meiosis I, and that this may be a major mechanism for trisomy formation rather than non-disjunction of whole bivalents at meiosis I, as generally believed.

Cells, Cultured↗
PubMed1991

Uterine activity and decidual prostaglandin production in women in early pregnancy in response to mifepristone with or without indomethacin in vivo.

Mifepristone stimulates uterine activity in pregnant women in the first trimester. In-vitro studies have shown that the addition of mifepristone to culture medium increases the ability of decidual cells to generate prostaglandins. In this study, pregnant women of less than 56 days gestation were treated with mifepristone (600 mg) 24, 36 or 48 h prior to surgical termination of pregnancy. Another cohort of women were similarly treated with mifepristone, but also received indomethacin (100 mg b.d.). Control groups, given indomethacin alone (100 mg b.d. for 48 h) or no treatment, were also included. Uterine activity was measured immediately prior to surgical termination of pregnancy and the ability of decidua obtained at operation to generate prostaglandins in culture was measured. Uterine activity was increased in all groups pretreated with mifepristone, an increase which was not prevented by co-administration of indomethacin. In the groups pretreated with mifepristone 36 h previously, the production of prostaglandin F2 alpha (PGF2 alpha) by decidua in vitro was increased. In the group in whom indomethacin was given in addition to mifepristone 36 h prior to the study, there was a marked reduction in the ability of decidua to generate PGF2 alpha. In spite of this suppression, the increase in uterine activity was similar to the group which had not received indomethacin. These results suggest that factors other than an increase in decidual prostaglandin production are responsible for the increase in uterine activity seen following mifepristone administration in vivo.

Culture Techniques↗
PubMed1991

The effect of stage of estrous cycle and follicular maturation on ovarian inhibin production in sheep.

Twenty-four Scottish Blackface ewes (mean weight 50.0 +/- 0.1 kg with ovulation rate 1.3 +/- 0.1) were randomly divided into 4 groups of 6 animals. Under general anesthesia, following the collection of a timed sample of ovarian venous blood, the ovaries of these animals were collected either on Day 10 of the luteal phase or 12, 24, and 48 h after a luteolytic dose of a prostaglandin (PG) F2 alpha analogue (cloprostenol 100 micrograms i.m.) administered on Day 10. All follicles greater than 3 mm were dissected from the ovaries and incubated in Medium 199 (M199) at 37 degrees C for 2 h, following which the granulosa cells were harvested and incubated in triplicate for 24 h in M199 with or without ovine FSH or ovine LH. Plasma and culture media samples were assayed for inhibin, estradiol (E2), androstenedione (A4), and testosterone (T) by specific RIA. After correcting for hematocrit, ovarian secretion rates were calculated from the product of the plasma concentration and flow rate. The rate of ovarian inhibin secretion during the luteal phase was similar from ovaries categorized on the basis of presence of luteal tissue (1.0 +/- 0.3 and 0.9 +/- 0.5 ng/min for CL present and absent, respectively), confirming that the ovine CL does not secrete appreciable amounts of inhibin. Inhibin secretion was higher (p less than 0.05) at 12 h after PG-induced luteolysis but not at 24 or 48 h compared to values for luteal phase control ewes. Although ovaries containing large estrogenic follicles (greater than or equal to 4 mm in diameter and classified as estrogenic from in vitro criteria) secreted the most inhibin (55%; p less than 0.05), both ovaries containing large nonestrogenic follicles (33%) and small (11%; less than 4 mm in diameter) follicles secreted appreciable amounts of inhibin. This contrasted strongly with E2 where greater than 80% of the steroid was secreted by large estrogenic follicles. The rate of ovarian inhibin secretion was positively correlated (p less than 0.05) with the rate of E2, A4, and T secretion. Overall, there was no significant effect of stage of cycle on follicular inhibin content after 2 h incubation in vitro, release of inhibin by follicles incubated in vitro, or synthesis of inhibin by granulosa cells cultured in vitro. FSH and LH had no effect on the production of either inhibin or estradiol by cultured granulosa cells. Follicular diameter was positively correlated (p less than 0.001) with follicular inhibin and steroid release. Follicular inhibin content after 2 h incubation in vitro was more highly correlated with inhibin release by incubated follicles (r = 0.7; p less than 0.001) than with inhibin synthesis by granulosa cells in vitro (0.4; p less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Control of immunoactive inhibin production by human granulosa cells.

OBJECTIVE: The aim was to determine the relation between stage of antral follicular development and granulosa cell production of immunoactive inhibin. DESIGN: Primary granulosa cell cultures in serum-free Medium 199 were incubated at 37 degrees C for 96 hours with a change of medium at 48 hours. Inhibin and steroid levels in culture medium were determined by radioimmunoassay. The inhibin assay was based on the N-terminal 1-26 amino acid sequence of the alpha-chain of porcine 32 kDa inhibin using pl alpha 1-26-GLY27-TYR28 as the immunogen, tracer and standard. PATIENTS: Granulosa cells were obtained from the ovaries of women with regular menstrual cycles undergoing hysterectomy with unilateral or bilateral oophorectomy to treat non-malignant gynaecological disease. RESULTS: Basal production of immunoactive inhibin by granulosa cells from presumptive preovulatory follicles (greater than 15 mm diameter) was 5-13 times higher than that by granulosa cells from immature (less than 10 mm diameter) or intermediately mature (10-15 mm diameter) follicles. Basal production of progesterone and oestradiol followed a qualitatively similar pattern, establishing a positive relation between functional granulosa cell maturity and inhibin production. Treatment of granulosa cell cultures from immature follicles with follicle-stimulating hormone (FSH), but not luteinizing hormone (LH), increased inhibin production, time and dose dependently. FSH, but not LH, also brought about similar increases in steroid hormone synthesis by granulosa cells from immature follicles. The stimulatory effect of FSH on granulosa cell inhibin production was augmented at least twofold by the presence of testosterone or 5 alpha-dihydrotestosterone (1.0 mumol/l) but was unaffected by oestradiol. Granulosa cells from intermediately mature follicles undertook variable degrees of both FSH and LH-responsive inhibin production which generally corresponded with gonadotrophin-responsive steroid production. Granulosa cells from presumptive preovulatory follicles showed inconsistent inhibin responses to FSH. However, LH caused marked (at least twofold) increases in inhibin production, paralleling LH-responsive steroid production. CONCLUSION: These results show that for human beings, granulosa cell capacity to produce immunoactive inhibin in vitro increases with follicular maturity. FSH, but not LH, stimulates inhibin production by immature granulosa cells and this response to FSH is subject to modulation by androgen. During preovulatory follicular development, production of inhibin, like steroids, becomes increasingly responsive to LH. Such a development-related pattern of granulosa cell inhibin production helps explain how, post-ovulation, the corpus luteum is able to secrete inhibin as well as steroids. It is also compatible with the concept that locally produced inhibin could participate in the paracrine control of follicular development during the human menstrual cycle.

Adult↗
PubMed1991

Effect of recombinant activin on androgen synthesis in cultured human thecal cells.

The effect of activin-A on ovarian androgen synthesis was tested in vitro using serum-free monolayer cultures of human thecal cells. Maximal rates of androgen (androstenedione and dehydroepiandrosterone) production were induced by treating the cells for 4 days with LH (10 ng/mL) in the presence of insulin-like growth factor-I (greater than or equal to 30 ng/mL). The additional presence of recombinant activin-A (1-100 ng/mL) in culture medium caused dose-dependent suppression of thecal cell androgen production, with 50% maximal inhibition occurring at an activin-A concentration of about 10 ng/mL. Progesterone production was only suppressed by high dose (100 ng/mL) activin-A, and inhibition of steroid production occurred without inhibition of DNA synthesis (tritiated thymidine uptake). These results reveal a potent and selective inhibitory action of activin-A on thecal cell androgen synthesis, consistent with a paracrine function for activin(s) in modulating follicular androgen biosynthesis in the human ovary.

Activins↗
PubMed1991

The source of inhibin secretion during the human menstrual cycle.

The source of inhibin secretion during the human menstrual cycle was investigated in two ways. The concentration of inhibin was compared in samples obtained from the ovarian and peripheral veins of 41 women undergoing hysterectomy. In 13 of the women, the corpus luteum was enucleated at operation and the peripheral concentration of inhibin measured at intervals for 24 h. Inhibin was assayed by a heterologous RIA using an antiserum raised against 31 kilodalton bovine inhibin. The concentrations of estradiol and progesterone in the peripheral and ovarian veins were similar to those previously reported. During the early follicular phase, the geometric mean inhibin concentrations were found to be significantly higher in both the right and left ovarian veins than the peripheral vein (180.4 and 157.7 vs. 78.7 U/L: P less than 0.02) but no difference was found in the late follicular phase between the vein draining the dominant ovary and the contralateral ovarian vein (231.1 vs. 193.4 U/L: NS). The inhibin concentrations in the veins draining the ovary bearing a corpus luteum were, however, significantly higher than those in the contralateral ovarian veins during the mid (409.1 vs. 203.6 U/L: P less than 0.02) and late (287.1 vs. 153.2 U/L: P less than 0.01) luteal phases. After enucleation of the corpus luteum, the inhibin concentration fell from the level seen before lutectomy (134.4 U/L) to 80.0 U/L at 24 h (P less than 0.01). This study demonstrates conclusively that the human corpus luteum secretes inhibin. No increase in inhibin secretion was seen from the dominant follicle in the late follicular phase. This casts doubt on the hypothesis that the selective suppression of FSH during the follicular phase is due to inhibin from the dominant follicle.

Adult↗