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F F Bartol

Publications and source records attributed to F F Bartol.

45 records · Page 3Linked to original sources
PubMed1987

Histogenesis of the ovine uterus.

Reproductive tracts from fetal (d 55 to 150) and neonatal (d 9 to 3 mo) lambs were examined by light microscopy in order to describe ovine uterine histogenesis. Morphologically, d-55 and -60 fetal uteri were bipartite, though characteristic external cornual morphology was not apparent until d 100 to 110. Histologically, lumina of d-55 and -60 fetal uteri were tubular and smooth with no indication of caruncular or glandular areas. In d-90 to -100 fetal uteri, luminal clefts were visible along the mucosal surface and a band of eosinophilic, elongated, smooth muscle-like cells was distinguishable. By d 100 to 110, nodular and internodular areas were clearly defined as luminal clefts deepened. Expansion of deep internodular areas, parallel to the luminal nodular surface, progressed in fetal uteri from d 118 to 150. Slight invaginations along deep internodular areas were visible in d-135 fetal uteri and were regular features of d-150 fetal uteri. In contrast, shallow, slightly coiled simple tubular glands were visible in the endometrium of internodular (intercaruncular) areas in a d-9 neonatal uterus. Older neonatal uteri (d 26 to 3 mo) contained coiled tubular glands which extended to the myometrium. Data indicate a systematic pattern of ovine uterine histogenesis involving dynamic morphogenetic alterations, especially between d 80 to 130 of fetal life. The observation that uterine glands were absent in fetal uteri but present in neonatal uteri suggests that glandular induction must occur during the periparturiet/neonatal period.

Animals↗
PubMed1986

Uterine prostaglandin and blood flow responses to estradiol-17 beta in cyclic cattle.

Normal cyclic dairy cattle (n = 7) underwent a midventral laparotomy on day 17 of the estrous cycle and were fitted, ipsilateral to the CL, with: an electromagnetic flow transducer around the uterine artery (UA; n = 5); catheters within the ovarian vein (OV; n = 7) via a uterine branch of the ovarian vein, uterine branch of the ovarian artery (UBOA; n = 5) and facial artery (FA; n = 7). On day 18, blood samples were collected at 30 min intervals for 1 h prior to injection of estradiol-17 beta (E2; 3 mg) and 12 h post-E2. Uterine blood flow (UBF) was monitored continuously and plasma samples analyzed for PGF2 alpha and PGFM. Exact locations of catheters in reproductive tracts were verified post-slaughter. Data were analyzed by method of least squares analysis of variance. Uterine blood flow (ml/min) increased above pre-E2 flow rates within 30 min post-E2 injection, peaked between 2.5 to 3.5 h and declined between 4 to 8.5 h. A small secondary rise in UBF occurred between 9 and 12 h. Regression analysis for concentrations (pg/ml) of PGF2 alpha and PGFM in the OV (i.e., [OV]-[FA]) demonstrate a similar response as PGFM concentration in the FA in that all increased at approximately 3 h, peaked between 5 and 7 h and returned to near baseline levels by 9 to 10 h post-E2. Facial artery PGFM concentrations were positively correlated with uterine production of PGF2 alpha (r = .66) and PGFM (r = .30), whereas FA PGF2 alpha concentrations were not. In three of five cows, a difference in PGF2 alpha was detected between UBOA and FA (UBOA greater than FA); supportive of a local countercurrent exchange between the uterine venous drainage and the ovarian artery.

Animals↗
PubMed1986

Developmental alterations in the regulation of glucagon and insulin secretion in Holstein calves.

Twenty-one Holstein bull calves were randomly assigned at birth to 3 groups. Two groups (each of 7 calves) were raised as follows: fed a milk diet alone or fed milk with grain supplementation after 2 weeks of age; studies were done when calves reached 4 weeks of age. The 3rd group was fed on milk with grain supplementation until weaning after which the calves were maintained on grain and pasture. These calves (older calves) were studied at 12 weeks of age. Either propionate (0.28 mmol/kg) or glucose (0.56 mmol/kg) was injected IV in a random order. Samples of blood were obtained from the calves before and immediately after injections were done and at 2, 5, 10, 15, 30, 45, and 60 minutes after secretagogue injection. Plasma was examined for glucose by a glucose oxidase procedure and for immunoreactive insulin (IRI) and glucagon (IRG) by radioimmunoassay. The IRI response to the injection of glucose was greater in older calves (P less than 0.02). Patterns of IRI secretion, as determined by heterogeneity of regression, showed age differences for both secretagogues (P less than 0.05). Base-line IRG was greater in milk/grain-fed calves than in milk-fed calves (P less than 0.05). Mean IRG response to propionate injection was higher (P less than 0.05) in milk/grain-fed calves than in milk-fed calves. Plasma glucose concentration increased in older calves, but decreased in milk-fed calves after propionate injection. The data indicate that maturation in the ruminant is accompanied by altered regulation of insulin and glucagon secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1985

Characterization of proteins produced in vitro by periattachment bovine conceptuses.

Bovine conceptuses from Days 16 (n = 4), 19 (n = 6), 22 (n = 3), and 24 (n = 4), and chorion from Day 69 (estrus/mating = Day 0) were cultured for 24 h in modified minimum essential medium (MEM) in the presence of radioactive L-leucine [( 3H] leucine) to characterize de novo synthesis and release of proteins. Proteins released into MEM were identified by two-dimensional polyacrylamide gel electrophoresis, fluorography, and gel and ion exchange chromatography. Major polypeptides identified in MEM were different from those identified in conceptus and chorionic tissues. Both uptake of [3H] leucine and quality of polypeptides produced de novo and released into MEM were related to stage of conceptus development. Percent retention of [3H] leucine in MEM was lowest (P less than 0.01) in Day 16 cultures (1.2 +/- 4.1%), increased in Days 19 (16.8 +/- 3.7%) and 22 cultures (20.9 +/- 5.8%), and decreased (P less than 0.07) in Day 24 cultures (6.9 +/- 4.1%). Complexity of polypeptides increased after Day 16. Days 16, 19, 22 and 24 conceptus culture MEM was enriched in low-Mr, acidic polypeptides (Mr/isoelectric point ranges: 22K-26K/6.5-5.6, 20K-26K/5.5-5.4, and 16K-20K/5.0-4.5), which were not prominent products of Day 29 and 69 tissues. A high-Mr (Mr +/- SEM; 735K +/- 22K) glycoprotein was produced by all conceptus and chorionic tissues. The transient nature of production of low-Mr polypeptides suggests that they may be required during the periattachment period.

Amino Acids↗
PubMed1985

Characterization of proteins produced in vitro by bovine endometrial explants.

Endometrial tissues were obtained from 17 pregnant (P, estrus/mating = Day 0; Day 16, n = 4; Day 19, n = 6; Day 22, n = 3; Day 24, n = 4) and six nonpregnant (NP; Day 16, n = 4; Day 19, n = 2) cattle, as well as from one cyclic (nonbred) cow (Day 4), one later-pregnant cow (Day 69), and both ligated and pregnant uterine horns of three unilaterally pregnant cattle (UP; Day 270). Tissues (approximately equal to 500 mg wet tissue/explant) were cultured for 24 or 48 h in modified minimal essential medium (MEM), in the presence of radioactive amino acid and/or amino sugar substrate(s) (L-[3H] leucine, L-[14C] leucine, and D-[3H] glucosamine), in order to characterize substrate uptake and de novo synthesis and release of proteins and polypeptides in vitro. Endometrial explants from all cattle produced proteins de novo from radiolabeled substrates. Chromatographic (gel filtration, cation, and anion exchange) and two-dimensional polyacrylamide gel electrophoretic analyses revealed complex patterns of primarily acidic radiolabeled polypeptides in dialyzed MEM, which were absent from endometrial tissue homogenates. No qualitative differences were noted in the array of proteins released into MEM associated with either pregnancy status (P vs. NP, UP) or stage of gestation (Days 16, 19, 22, 24, 69, and 270). Medium from all endometrial explants was enriched in polypeptides in four Mr (X 10(3)/pH classes (I, approximately equal to 14/greater than 7.2; II, 19-24/5.4-6.3; III, 28-31/6.9-7.3; and IV, greater than or equal to 150/less than or equal to 5.1).

Amino Acids↗
PubMed1984

Maternal recognition of pregnancy in cattle.

Nature and potential functions of chemical signals involved in the process of pregnancy recognition in cattle are discussed. The array of prostaglandins, steroid metabolites, and proteins produced by the conceptus and endometrium are described and collated with histological and physiological responses of the uterus and ovary that lead toward maintenance of the corpus luteum. Advances during the last 10 yr partially have identified the conceptus-endometrial-ovarian signal sequence that is associated with maternal recognition of pregnancy in cattle. Final evaluation of the control system should permit investigators to improve embryo survival and augment further the impact of embryo manipulation to improve genetic merit of the cattle population.

Animals↗
PubMed1983

A function of the allantoic sac in the metabolism of uteroferrin and maternal iron by the fetal pig.

The possible roles of the allantoic sac in metabolism of uteroferrin, the iron-containing, purple phosphatase, were examined. This protein, which originates in the maternal endometrium, was measured in allantoic fluid by a specific double-antibody radioimmunoassay and by its beta-mercaptoethanol-activated acid phosphatase activity. Total uteroferrin reaches a maximum between days 60 and 75 of pregnancy, when it constitutes up to one-third of the total protein, and then declines towards term. Fluid volume, total protein and total iron also reach a maximum around day 60. Two-dimensional polyacrylamide-gel electrophoresis was employed to identify proteins in allantoic fluid. Of the proteins detected, at least three basic and two acidic polypeptides are also characteristic of maternal uterine secretions. The remaining proteins appeared identical to those found in fetal serum and included transferrin, albumin and alpha-fetoprotein. Although uteroferrin acid phosphatase activity is stable when incubated in buffer, the enzyme loses activity in sterile allantoic fluid collected at all stages of pregnancy. Experiments with 59Fe-uteroferrin have shown that allantoic fluid promotes iron loss from uteroferrin and that the metal appears in transferrin. Thus the allantoic sac may serve not only as a depot for uteroferrin accumulation but as a site of active iron metabolism.

Acid Phosphatase↗
PubMed1981

Effect of estradiol-17beta on PGF and total protein content in bovine uterine flushings and peripheral plasma concentration of 13, 14-dihydro-15-keto-PGF(2alpha).

Two experiments were conducted to examine the effect of estradiol-17beta (E(2)-17beta) on content of immunoreactive prostagladin F(2)alpha (PGF, ng) and total protein (TUP, mg) in uterine flushings, as well as concentrations of 13, 14-dihydro-15-keto-PGF(2)alpha (PGFM) in plasma (Pg/ml). In experiment 1, Holstein heifers were utilized in a single reversal trial in which either E(2)-17beta (3 mg in 2 ml saline/ethanol 50:50; n=5) or vehicle alone (n=6) were given intravenously on day 14 or 15 of the estrous cycle (Period 1) following an induced estrus (day of estrus = day 0). Treatment (Trt) groups were reversed in Period 2 (Day 14 or 15 of the second estrous cycle). Jugular venous plasma was obtained before treatment (Oh), and at 5, 6, and 9h posttreatment (PT). Uterine flushings were collected nonsurgically in vivo , per cervix, via Foley catheter at 6h PT (20 ml of .9% saline per uterine horn). E(2)-17beta did not significantly alter (E(2)-17beta vs vehicle; x(-) +/- S.E.M.) PGF (1674 +/- .11 +/- 338.39 vs 1889.91 +/- 400.24 ng; P> .10) or TUP (33.25 +/- 2.57 vs 39.16 +/- 3.04 mg; P > .10). However, E(2)-17beta increased (P < .05) plasma PGFM (E(2)-17beta vs vehicle) after treatment (0h, 113.2 vs 163.8; 5h, 312.5 vs 203.9; 6h, 324.5 vs 198.0; 9h, 323.2 vs 246.8, pg/ml). In experiment 2, crossbred beef cattle received comparable treatments of either E(2)-17beta (n=5) or vehicle (n=5) on day 14 or 15 postestrus. Jugular venous plasma was obtained at 0h PT, and at 6h PT. Uterine flushings (1.9% saline, 20 ml per uterine horn) and peripheral plasma were collected at slaughter. Estradiol-17beta increased PGF (30.07 +/- 5.94 vs 8.46 +/- 2.01 ng; P> <.05) in uterine flushings as well as PGFM in plasma (E(2)-17beta : 55.82 +/- 19.13 pg/ml, at 0h and 89.31 +/- 14.02 pg/ml, at 6h, vs saline: 103.46 +/- 50.73 pg/ml, at 0h and 17.78 +/- 14.22, at 6h). Estradiol-17beta stimulated uterine production and release of PGF and protein as measured in flushings (experiment 2) as well as plasma PGFM responses (experiments 1 and 2). Uterine and/or cervical stimulation of experiment 1 may have masked uterine response to E(2)-17beta.

Journal Article↗