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Biomedical subjects

G D Hodgen

Publications and source records attributed to G D Hodgen.

At least 37 records · Page 2Linked to original sources
PubMed1996

Role of hypoestrogenism or sex steroid antagonism in adhesion formation after myometrial surgery in primates.

OBJECTIVE: To determine the contribution of estrogen in the development of pelvic adhesions during myometrial surgery. DESIGN: A randomized, prospective study in the nonhuman primate. SETTING: A primate colony, Department of Obstetrics and Gynecology, Eastern Virginia Medical School. INTERVENTIONS: All primates were assigned prospectively to one of three treatment groups: [1] GnRH analogue (GnRH-a), [2] mifepristone, or [3] vehicle control. After 3 months of treatment, a standard uterine fundal hysterotomy, for full thickness endometrial biopsy, was performed at the time of exploratory laparotomy, with subsequent scoring of utero-omental adhesions to the hysterotomy site at a future staging procedure based upon adhesion area, vascularity, and tenacity. Serum was drawn on the day of surgery for E2 determination. Endometrial height, from the surface interface between the endometrium and myometrium, was used as a bioassay of estrogen activity. RESULTS: The hypoestrogenic (GnRH-a) group and the mifepristone group had significantly fewer utero-omental adhesions compared with the normally cycling control monkeys as measured by a lower adhesion score. Similarly, the endometrial thickness was significantly reduced in the GnRH-a and mifepristone groups (one-third) compared with the cycling controls, demonstrating the effects of either hypoestrogenism or noncompetitive estrogen antagonism. Serum E2 on the day of surgery was predictive of the postoperative adhesion score by both a regression analysis and analysis of covariance. CONCLUSIONS: The actions of E2 seem to have a dramatic effect on the formation of pelvic adhesions after myometrial surgery.

Animals↗
PubMed1995

Activation of the hypothalamo-anterior pituitary corticotropin-releasing hormone, adrenocorticotropin hormone and beta-endorphin systems during the estradiol 17 beta-induced plasma LH surge in the ovariectomized monkey.

The present work describes time-dependent changes in the content of corticotropin-releasing hormone (CRH), adrenocorticotropin (ACTH), and beta-endorphin (beta-EP) in the hypothalamus (HT) and anterior pituitary (AP) and in the concentration of ACTH and beta-EP in the plasma during the 17 beta estradiol (E2) benzoate (E2B)-induced luteinizing hormone (LH) surge in ovariectomized cynomolgus monkeys. Monkeys were euthanized at 0, 30, 48, 72, and 96 hr post-E2B. HT and AP were rapidly dissected, extracted in 2 N acetic acid containing 1 mM phenylmethane sulfonyl fluoride at 4 degrees C, and centrifuged at 18,000g for 30 min. Peptide concentrations were measured in the supernatant by specific radioimmunoassays (RIAs). In the HT, there were significant (P < 0.05) decreases in ACTH and beta-EP content by 30 hr post-E2B and a significant (P < 0.05) decrease in HT CRH content 48 hr post-E2B. Thereafter, CRH, ACTH, and beta-EP content increased up to 72 hr post-E2B. In the AP, there was an almost linear decrease in the CRH content through 48 hr post-E2B followed by a marked 20-fold (P < 0.01) increase in the AP CRH content at 72 hr post-E2B, which corresponds to the time of the descending arm of the LH surge. The patterns of ACTH and beta-EP content were very similar in the AP, while that of CRH differed markedly. In contrast, in the HT CRH, ACTH, and beta-EP profiles were very similar. Significant (P < 0.05) increases in circulating levels of ACTH, beta-EP, and cortisol were evident at 30 hr (all 3 hormones), 48 hr (beta-EP and cortisol), and 72 hr (cortisol) post-E2B, which corresponds with the time of decreased hypothalamic content of CRH, ACTH, and beta-EP. These results suggest that there maybe a marked activation of the hypothalamo-anterior pituitary-adrenal axis during the negative and positive feedback phases of the E2B-induced LH surge in the ovariectomized monkey.

Adrenocorticotropic Hormone↗
PubMed1995

Mechanism for species-specific induction of Leydig cell tumors in rats by lansoprazole.

Lansoprazole is a substituted benzimidazole which inhibits gastric acid secretion by inhibiting the hydrogen-potassium ATPase (proton pump) in the parietal cell. The finding of Leydig cell hyperplasia and Leydig cell tumors in 2-year oral studies in Sprague-Dawley rats but not in CD-1 mice prompted investigative studies to determine the mechanism for the Leydig cell changes. hCG challenge studies in Sprague-Dawley rats revealed decreased testosterone responsiveness in rats treated orally for 1 or 2 weeks with lansoprazole. After 4 weeks of daily oral treatment increases in serum LH and decreases in serum testosterone were detected within a few hours after dosing. In a study where 9-month-old male F344 rats were given testosterone supplementation via Silastic implants and then treated with lansoprazole for 6 months, a high incidence of Leydig cell tumors was seen in lansoprazole-treated, unsupplemented rats, whereas no Leydig cell tumors were seen in testosterone supplemented rats. This implied that reduction of the normal feedback inhibition at the level of the hypothalamus and/or pituitary due to reduced testosterone levels, thus giving rise to elevated levels of LH, was involved in the induction of Leydig cell tumors by lansoprazole. In vitro studies with Leydig cells from rats using various stimulators and precursors of testosterone biosynthesis demonstrated that the most sensitive site for inhibition of testosterone synthesis by lansoprazole is the transport of cholesterol to the cholesterol side chain cleavage enzyme. The IC50s for inhibition of LH or hCG-stimulated testosterone synthesis in Leydig cells from rats, mice, and monkeys were 11-12, 8, and 24.7 micrograms/ml, respectively. In vitro studies with metabolites of lansoprazole revealed that three metabolites were more potent inhibitors of testosterone synthesis than the parent drug, two of them being at least 10 times more potent. These metabolites are present in rats at substantial levels but are undetectable in humans. The lack of induction of Leydig cell tumors in mice, lower sensitivity of primate Leydig cells, and the absence of testosterone synthesis-inhibiting metabolites in man suggest that Leydig cell tumors found in rats represent a species-specific sensitivity and does not imply a risk for clinical use in man.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1995

Estrogen and progesterone receptor mRNA are expressed in distinct pattern in male primate reproductive organs.

PURPOSE: The role(s) of estrogens (E) and progesterone (P) in male reproductive physiology remain unclear. Estrogens are used in the treatment of prostatic cancer. Progestins have been used to control excessive sexual behavior in men, and proposed as a male contraceptive. Previous immunohistochemical studies have shown that E receptors (ER) are present in the reproductive tract of male nonhuman primates. METHOD: We examined the expression pattern of ER and progesterone receptor (PR) mRNA in adult primate male reproductive tract. mRNA was extracted from male pituitary, testis, prostate and different regions of the epididymis of three intact adult cynomolgous monkeys. Ovarian, myometrial and spleen mRNA were used as controls. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to amplify ER and PR mRNA; beta-actin mRNA was used as a reference. Primers for ER, PR and beta-actin were designed using the most conserved areas in the corresponding human cDNA sequences, and the identity of the PCR products was verified using Southern hybridization. Semiquantitative analysis of ER and PR mRNA content in different parts of the male reproductive tract was carried out by spiking the PCR reaction with 33P-dCTP, and amplifying the samples for 20 cycles with the beta-actin primers, whereas 30 cycles were used for ER and PR. RESULTS: The results are expressed as cpm ratios of ER or PR/beta-actin. All the male reproductive organs studied revealed a strong signal for ER and PR mRNA. The results of the semiquantitative analysis indicate that the expression of both ER and PR was highest in testis (mean +/- SE 6.4 +/- 1.3 and 0.5 +/- 0.1, respectively). The mean figures for prostate were 0.5 and 0.4, respectively. The mean content of ER and PR in the different areas of epididymis was 0.5 and 0.1, respectively. The epididymal ER mRNA was highest in the corpus region (ER/beta-actin 0.7), the ratio being 0.4 for the caput and cauda regions. The expression pattern of PR mRNA was different, and the caput of epididymis being the most intense (0.2). Surprisingly, the pituitary content of ER and PR mRNA was close to that seen in the ovary, the mean +/- SE values being 7.6 +/- 0.5 and 1.3 +/- 0.1, respectively. CONCLUSIONS: We, therefore, conclude that male monkey reproductive tract contains mRNA for ER and PR, and there appears to be regional variation in their expression. Thus the role(s) of Es and P in male reproductive physiology, specifically in sperm maturation, warrants further investigations.

Actins↗
PubMed1995

Pharmacokinetics of a single dose of buccal testosterone.

The bioavailability, pharmacokinetics, and metabolism of a novel transbuccal delivery system of testosterone was investigated in five healthy eugonadal men. Total serum testosterone (T), dihydrotestosterone (DHT), and sex hormone-binding globulin (SHBG) concentrations were determined from blood samples obtained at 8:00 a.m. (zero hour), and 30 min and 1, 2, 3, 4, 6, 12 and 24 hours later on day 1, and again on day 2, after dosing. This single transbuccal administration of Buccal T induced a prompt rise in serum T and DHT concentrations. The maximal concentration (Cmax) of T was 19.56 7.64 ng/mL (mean +/- SD; 5.3-fold increase from the baseline) at< 30 min (Tmax) after administration. The elimination half-life of Buccal T was about 1.75 h. Serum DHT peaked at 1 h at a concentration of 1.46 +/- 0.46 ng/mL (2.3-fold increase from the baseline). The drug was well tolerated. This study suggests that the Buccal T is a promising delivery system for natural T.

Administration, Buccal↗
PubMed1995

Prediction of ovarian response to exogenous gonadotropin stimulation: utilization for collection of primate oocytes for fertilization in vitro.

The predictive value of 2 tests for ovarian response to controlled ovarian hyperstimulation in the cynomolgus monkey model was evaluated. The tests utilized were: 1) the cycle Day 3 (Day 1 = onset of menses) FSH value and 2) the acute estradiol (E(2)) response to a GnRH agonists (GnRHa) administered on Day 3. Both tests were performed during the cycle preceding control ovarian hyperstimulation. Subsequently, monkeys (n = 26) were stimulated with Metrodin(T) (Days 2-6, 25IU/d) and Pergonal(T) (Day 7 to hCG administration, 25IU/d). Laparoscopic oocyte retrieval was performed 32 to 34 after hCG administration. Analysis of the data revealed that Day 3 FSH values could not predict whether an animal would respond well to control ovarian hyperstimulation in a subsequent cycle (P = 0.77). However, the E(2) change 24 h post-GnRHa administration was significantly greater for animals responding well to control ovarian hyperstimulation compared with the animals deleted after 6 d of stimulation (P = 0.042). The mean change in E(2) levels in animals taken to aspiration was 97.8 pg/ml compared with only 21.6 pg/ml for the deleted animals. This differential response of E(2) production after GnRHa treatment was used to correctly identify (by discriminant analysis) 78% of the animals subsequently deleted for poor response. Thus, the increase in serum E(2) level after GnRHa, but not the basal FSH level, was found to be predictive of ovarian response to stimulation in the cynomolgus monkey.

Journal Article↗
PubMed1995

Factors affecting fertilization: endometrial placental protein 14 reduces the capacity of human spermatozoa to bind to the human zona pellucida.

OBJECTIVE: To examine whether placental protein 14 (PP14) may affect directly those sperm functions crucial to fertilization and early embryo development. DESIGN: In these prospective studies, we evaluated semen samples of fertile men incubated under capacitating conditions with and without PP14. SETTING: Academic tertiary institution. INTERVENTIONS: Biologically active PP14 was purified from human midtrimester amniotic fluid by anion exchange and immunoaffinity chromatography. After separation of the motile fraction, spermatozoa were incubated for 30 minutes with or without PP14 (concentration range of 0.01 to 100 micrograms/mL), washed, and then aliquots were prepared for use in the different assays. Human sperm-zona pellucida (ZP) binding was assessed using the hemizona assay (HZA) in a 4-hour gametes coincubation period. Sperm motility parameters were evaluated using a computerized semen analyzer. The acrosome reaction (AR) was determined by fluorescein isothiocyanate-conjugated Pisum sativum agglutinin and indirect immunofluorescence. MAIN OUTCOME MEASURES: Sperm-ZP binding, sperm motility patterns, and AR. RESULTS: Preincubation of sperm (and not the hemizonae) with PP14 produced a significant and dose-dependent inhibition of binding in the HZA. Monoclonal antibodies generated against PP14 showed no direct effect in the HZA and partially neutralized the inhibitory activity of PP14 in the HZA. Insulin-like growth factor binding protein-1 (IGFBP-1), an endometrial stromal cell product, showed no effect in the HZA. Neither PP14 nor IGFBP-1 interfered with sperm motility parameters or the AR. CONCLUSIONS: Placental protein 14 produced a potent, fast, and dose-dependent inhibition of binding of human spermatozoa to the human ZP without affecting other prefertilization events (i.e., hyperactivated motility or AR). The detrimental effect on sperm-zona interaction seems to be specific for this endometrial epithelial protein (not observed with an endometrial stromal product) and may have fundamental bearance to the fertilization process thus providing a mechanism for endometriosis-related infertility.

Acrosome↗
PubMed1995

Preimplantation genetic diagnosis for Tay-Sachs disease: successful pregnancy after pre-embryo biopsy and gene amplification by polymerase chain reaction.

OBJECTIVE: To determine the ability to apply preimplantation genetic diagnostic techniques to screen for and prevent Tay-Sachs disease (TSD). DESIGN: A couple, both carriers for the 4 base pair (bp) insertion in exon 11 of the beta-hexosaminidase A gene, which results in TSD, underwent IVF, pre-embryo biopsy, polymerase chain reaction (PCR) DNA amplification of the biopsied blastomeres, and pre-embryo transfer. One to two blastomeres were aspirated using a biopsy pipette that was inserted through an opening in the zona formed with acidified phosphate buffer. Polymerase chain reaction was performed on the individual blastomeres for 20 cycles followed by an additional 30 cycles using nested primers. This yielded amplified DNA products of 272 and 276 bp for the normal and mutant gene, respectively. Heteroduplex formation was used for identification of normal, homozygous affected, and heterozygous pre-embryos. RESULTS: Seven of 13 oocytes fertilized normally and were biopsied at the four- to eight-cell stages. Deoxyribonucleic acid amplification occurred in four of seven pre-embryos (one homozygous affected and three homozygous normal pre-embryos). The three normal pre-embryos that continued to cleave after biopsy were transferred on the evening of day 3 after retrieval. Subsequently, a single gestational sac was observed and the genetic diagnosis was confirmed at amniocentesis. CONCLUSION: A successful pregnancy and birth were accomplished after preimplantation genetic diagnostic screening for the prevention of TSD.

Base Sequence↗
PubMed1995

Evaluation of the meiotic spindle apparatus in oocytes undergoing intracytoplasmic sperm injection.

OBJECTIVE: To determine whether intracytoplasmic sperm injection has an adverse effect on the meiotic spindle of oocytes after injection of a sperm into the ooplasm. DESIGN: Hamster oocytes were injected with human sperm (Test group) and evaluated for meiotic spindle and chromosome morphology using immunofluorescent staining. Results were compared with control uninjected oocytes exposed to the microscope environment (CS group) and untreated oocytes remaining in the incubator (CI group). SETTING: Basic research center at a medical school. RESULTS: No significant differences were noted in spindle appearance and chromosome alignment between Test (13 abnormal/68 normal) and both control groups (CS 9/73 and CI 12/71; P = 0.602). CONCLUSION: Our results demonstrate that injection of human sperm into the cytoplasm of hamster oocytes may not result in a significant increase in damage to the meiotic spindle provided care is taken to orient the polar body away from the site of injection.

Animals↗
PubMed1995

The role of endothelin-1 in regulating human granulosa cell proliferation and steroidogenesis in vitro.

The effects of endothelin-1 (ET-1) on luteinized human granulosa cells (L-HGCs) have not been examined. It is well known that there are differences of actions of several autocrine/paracrine regulators between L-HGCs and GCs of other species, and therefore the present study was designed to examine the effects of ET-1 1) on intracellular Ca2+ concentrations ([Ca2+]i) using the Ca(2+)-responsive fluorescent indicator Fura-2, 2) on cell proliferation by the nonradioactive method using bromodeoxyuridine, and 3) on basal and gonadotropin-stimulated steroidogenesis, and to examine the expression of ET receptor messenger RNA (mRNA) using freshly isolated and cultured L-HGCs obtained from patients undergoing in vitro fertilization. ET-1 increased [Ca2+]i in L-HGCs in a dose-dependent manner between 1 and 1000 nmol/L. High concentrations (100-1000 nmol/L) of ET-1 produced a more rapid and transient increase in [Ca2+]i than that observed with low concentrations (1-10 nmol/L) of ET-1. The increase in [Ca2+]i elicited by ET-3 (1000 nmol/L) and IRL-1620 (1000 nmol/L), a selective ETB receptor agonist, was 16% and 3% (vs. ET-1, 100%), respectively. BQ-123 (1000 nmol/L), an ETA receptor antagonist, inhibited the increase in [Ca2+]i elicited by ET-1 (by 50% at 1000 nmol/L ET-1 and by > 90% at < 500 nmol/L ET-1). mRNAs for the two known receptor subtypes (ETA and ETB) were also present in L-HGCs; however, the expression of ETA receptor mRNA was much greater than that of ETB receptors. ET-1 stimulated cell proliferation in L-HGCs in a dose-dependent manner (1000 nmol/L, 210.5 +/- 13.1%; 100 nmol/L, 198 +/- 11%; 10 nmol/L, 146 +/- 18%; and 1 nmol/L, 103 +/- 9%; vs. control, 100%). These stimulatory effects were completely blocked by BQ-123 (1000 nmol/L). ET-3 and IRL-1620 had no effects on cell proliferation in L-HGCs. Significant stimulatory effects on cell proliferation by the calcium ionophore, ionomycin (10-1000 nmol/L), were observed. ET-1, ET-3, and IRL-1620 attenuated basal progesterone secretion in L-HGCs. These results suggest that ETA receptor predominantly exist in L-HGCs and that ET-1 may stimulate cell proliferation of L-HGCs by increasing [Ca2+]i via ETA receptors.

Calcium↗
PubMed1995

Antiovulatory actions of RU 486: the pituitary is not the primary site of action in vivo.

Continuous administration of RU 486 impairs follicular development and inhibits ovulation in women. Yet, the mechanism of ovulation inhibition remains unknown. To characterize the mechanism(s) of ovulation inhibition, we studied six regularly menstruating cynomolgus monkeys for three consecutive (control-rest-treatment) cycles. Monkeys received 1 mg/kg.day RU 486 in between cycle days 2-22. Basal and GnRH-stimulated (1 and 50 micrograms GnRH, iv, 2 h apart) secretion of LH and FSH was assessed using serial blood samples (every 15 min for 12 h) collected on cycle day 10. Serum levels of estradiol (E2), progesterone (P4), RU 486, cortisol, LH, FSH, and PRL were analyzed by RIAs, the bioactivity of LH was assessed using a mouse Leydig cell assay. The mean cycle length was prolonged by RU 486 treatment from 31.8 to 69.8 days (P = 0.008). During RU 486 treatment, patterns of E2 secretion varied considerably; the mean +/- SD E2 level was 204 +/- 139 pmol/L. LH peaks and P4 profiles compatible with luteal function were seen only before resumption of menstruation. However, one monkey had an increase in P4 after the GnRH challenge-induced LH secretion. Basal levels of LH varied between suppressed and apparently normal values, whereas basal FSH seemed little affected by RU 486 treatment. In two monkeys with E2 secretion indicative of normal follicular development, minor peaks of LH, but no rises in serum P4, were seen. The ratio of bioactive/immunoactive LH was reduced in these monkeys during RU 486 treatment compared to that during the washout period of the treatment cycle. Surprisingly, the pituitary responsiveness to acute GnRH challenge was not affected by RU 486 administration. The individual levels of RU 486 were similar during the treatment period (mean, 40 nmol/L). A resumption of ovulatory cycles occurred when RU 486 concentrations were below 2.5 nmol/L. We conclude that in cynomolgus monkeys, inhibition of ovulation by RU 486 occurs mainly at the level of the hypothalamus, with possible additional effects on the granulosa cell function and alterations of LH bioactivity.

Animals↗
PubMed1994

The reduction of postoperative adhesions by two different barrier methods versus control in cynomolgus monkeys: a prospective, randomized, crossover study.

OBJECTIVES: To determine the effectiveness of two different surgical membranes in preventing postoperative adhesions as compared with control and to evaluate the benefit as compared with "second-look" adhesiolysis. DESIGN: A randomized, prospective, crossover study. SETTING: A colony of individually caged non-human primates, Department of Obstetrics and Gynecology, Eastern Virginia Medical School Norfolk, Virginia. INTERVENTIONS: Hysterotomy or adhesiolysis at the time of exploratory laparotomy, with subsequent scoring of adhesions based on area, vascularity, tenacity, and adhesion score. RESULTS: The combined crossover data reveal that both surgical barriers are superior in adhesion prevention to microsurgical technique alone. Expanded polytetrafluoroethylene (Gore-Tex Surgical Membrane; WL Gore and Associates, Flagstaff, AZ) was better than oxidized regenerated cellulose (Interceed; Johnson and Johnson Medical, Inc., Arlington, TX) with respect to adhesion area, tenacity, and vascularity, with a significant improvement in the total adhesion score. Second-look adhesiolysis resulted in significant adhesion reduction in the control group, making second-look adhesiolysis statistically similar to the use of either barrier alone (without subsequent adhesiolysis). Gore-Tex removal does not result in adhesion formation as determined by third-look surgery. CONCLUSIONS: Both Interceed and Gore-Tex show a reduction in the prevention of postsurgical adhesions after hysterotomy incisions, as compared with microsurgical technique alone. Second-look adhesiolysis is as effective as either barrier in the reduction of permanent pelvic adhesions.

Animals↗
PubMed1994

Hypothalamo-pituitary effects of RU486: inhibition of progesterone-induced hyperprolactinaemia.

Monkeys given oestrogen priming at physiological levels for at least 1 week become hyperprolactinaemic upon the addition of physiological progesterone administration. Here, using RU486, we test whether that this oestrogen/progestin-induced hyperprolactinaemia results from classical progesterone actions at the hypothalamo-pituitary level. Blood samples were collected daily from study day 1-67. Each monkey (n = 2) received daily injections of 25 micrograms/kg oestradiol benzoate, i.m., on study days 5-60. Progesterone-filled silastic capsules (3 cm) were inserted on study day 14 and removed on day 53. On study days 39-45, each monkey received RU486 (25 mg/day, p.o.). Serum samples were stored at -20 degrees C until assayed for prolactin, oestradiol, progesterone and RU486 by radioimmunoassay. Hyperprolactinaemia was induced in all three monkeys upon insertion of progesterone capsules. Prolactin concentrations fell sharply during RU486 treatment to nadirs some 10-fold less than prior to RU486 treatment. The time series was modelled by the Box-Jenkins autoregressive-integrated moving average (ARIMA) method with progesterone producing a gradual increase in prolactin concentrations and RU486 producing a sudden decrease. Statistically significant effects of progesterone and RU486 were found. Thus, the addition of progesterone to an oestrogenized milieu significantly increased prolactin concentrations, and RU486 fully reversed this effect. This evidence indicates that the progesterone-induced hyperprolactinemia in an oestrogenized milieu results from classical progesterone effects.

Animals↗
PubMed1994

Non-competitive anti-oestrogenic activity of progesterone antagonists in primate models.

We have summarized some of the studies containing basic biological data suggesting potential therapeutic utility of the anti-proliferative activity of antiprogestins on uterine tissues. The non-competitive anti-oestrogenic effects of RU486 were examined using oestradiol-treated ovariectomized monkeys given RU486, progesterone or both. The oestradiol-induced luteinizing hormone surge of control animals was abrogated by progesterone and/or RU486. Secretory transformation by progesterone was inhibited by RU486 co-administration. RU486 alone (1 mg/kg) induced endometrial secretory transformation, but higher doses (5 mg/kg) induced inhibited proliferation and secretory activity. Thus, in the presence of progesterone, RU486 is antagonistic but, in its absence, RU486 exhibits endometrial progestational effects at low doses and an anti-proliferative (anti-oestrogenic) effect at higher doses. These data encourage continued evaluation of RU486 as a potential contraceptive agent acting at the pituitary and/or endometrial level. Our study also demonstrates that after physiological oestradiol replacement therapy, oestradiol receptor concentrations rise dramatically following antiprogestin treatment; this effect was dose-dependent.

Animals↗
PubMed1994

A sequential analysis of the effect of progesterone on specific sperm functions crucial to fertilization in vitro in infertile patients.

The objective of these studies was to evaluate the modulatory effect(s) of progesterone on sperm functions crucial to fertilization in infertile men with abnormal sperm parameters. A prospective, controlled study applying a sequential diagnostic analysis capable of identifying specific dysfunctions of the male gamete was performed. Patients (n = 14) were allocated to the study group if they had a history of infertility of > 1 year duration and after semen evaluation showed teratozoospermia (< 14% normal sperm forms as diagnosed by strict criteria) or terato-asthenozoospermia (< 50% progressive motility). After swim-up separation of the motile sperm fraction, the following functions were assessed with and without previous exposure to progesterone (1.0 micrograms/ml): acrosome reaction (using Pisum sativum agglutinin), hyperactivated motility (using a computerized semen analyser), sperm-zona pellucida binding (in the hemizona assay), sperm-zona pellucida penetration (in a sperm-zona penetration assay), and sperm-oocyte penetration (using the hamster zona-free oocyte/sperm penetration assay). Progesterone did not affect the percentage of acrosome-reacted spermatozoa after 1 or 3 h of incubation. Hyperactivated motility was significantly enhanced by progesterone after 1 h (12 +/- 4 versus 6 +/- 2% in controls; P < 0.02). Although progesterone did not affect sperm-zona binding, it significantly enhanced both sperm-zona pellucida penetration (27 versus 12% in controls; P = 0.03) and sperm-oocyte penetration (15 versus 8% in controls; P < 0.05). Because those sperm functions enhanced by progesterone are crucial to fertilization, the steroid may have value in the treatment of some male-factor patients undergoing assisted reproductive therapy.

Acrosome↗
PubMed1994

Early follicle growth in the juvenile macaca monkey ovary: the effects of estrogen priming and follicle-stimulating hormone.

The mechanism(s) that drives preantral and early antral follicle growth in the primate ovary is poorly understood. We previously reported that estrogen does not stimulate preantral or early antral follicle growth in juvenile primates. The purpose of the present study was to determine whether estrogen priming may play a role in enhancing FSH-stimulated follicle growth. Eight juvenile monkeys received implants on Day 1 of silastic capsules containing estradiol (or vehicle) to elevate circulating estradiol levels. Daily FSH injections were initiated on Day 4 and continued for up to 12 days. The left ovary was removed on Day 8 and served as a control. Ovulation was induced, and a luteal phase followed. On the first day of menses, the estradiol (vehicle) capsule-FSH protocol was repeated. The remaining ovary was removed on Day 8 of the second cycle. The number and size of all follicles in both ovaries were evaluated by light microscopy. Results indicate that estrogen priming in the first cycle did not enhance growth of preantral or antral follicles, but did result in fewer developing follicles > 1.0 mm in diameter, this was accompanied by an increase in early atretic antral follicles of similar size. In the second cycle, an even further reduction in number and size of developing antral follicles > 1.0 mm in diameter was observed. These data suggest that pretreatment with exogenous estrogen has an anti-follicular action on follicle growth in these primates.

Animals↗
PubMed1994

Anti-ZP3 antibodies binding to the human zona pellucida: effect of oocyte-storage conditions.

PROBLEM: The zona pellucida protein 3 (ZP3) is a zona pellucida (ZP) glycoprotein crucially involved in fertilization. ZP3 plays a major role in sperm binding and induction of the acrosome reaction. In different species, ZP3 proteins differ in their primary structure as derived from cDNA clones. The hemizona assay (HZA) is a bioassay that evaluates binding of human sperm to human ZP and is highly predictive of fertilization outcome under in vitro conditions. METHOD: In these studies, we used antisera generated against synthetic ZP3 peptides to compare antibody binding patterns to ZP with sperm-ZP binding capacity under different HZA conditions. RESULTS: Analysis of antibody binding to hemizonae derived from metaphase II human oocytes that were used either after refrigeration at 4 degrees C or stored in a hyperosmotic salt solution revealed a strong reaction with human ZP3. However, treatment of human oocytes using a protocol to freeze embryos with the addition of 1,2 propanediol drastically reduced binding of ZP3 antibodies to the hemizonae. Nevertheless, no significant difference of sperm binding occurred under HZA conditions when oocytes were refrigerated, salt-stored, or frozen with 1,2 propanediol. CONCLUSIONS: Our results indicate that the ZP3 protein backbone might be altered by 1,2 propanediol-treatment while the glycoprotein-receptor remains intact. We conclude that antisera against ZP3 peptides can be used as markers for the ZP3 protein backbone in human oocytes and might be useful tools for the evaluation of ZP3 protein integrity.

Cells, Cultured↗