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Background: The Sertoli cells act to induce testis differentiation and subsequent development in fetal and post-natal life which makes them key to an understanding of testis biology. As a major step towards characterisation of factors involved in Sertoli cell function we have identified Sertoli cell-specific transcripts in the mouse testis and have used the data to identify Sertoli cell-specific transcripts altered in mice lacking follicle-stimulating hormone receptors (FSHRKO) and/or androgen receptors (AR) in the Sertoli cells (SCARKO). Results: Adult iDTR mice were injected with busulfan to ablate the germ cells and 50 days later they were treated with diphtheria toxin (DTX) to ablate the Sertoli cells. RNAseq carried out on testes from control, busulfan-treated and busulfan + DTX-treated mice identified 701 Sertoli-specific transcripts and 4302 germ cell-specific transcripts. This data was mapped against results from microarrays using testicular mRNA from 20 day-old FSHRKO, SCARKO and FSHRKO.SCARKO mice. Results show that of the 534 Sertoli cell-specific transcripts present on the gene chips, 85% were altered in the FSHRKO mice and 94% in the SCARKO mice (mostly reduced in both cases). In the FSHRKO.SCARKO mice additive or synergistic effects were seen for most transcripts. Age-dependent studies on a selected number of Sertoli cell-specific transcripts, showed that the marked effects in the FSHRKO at 20 days had largely disappeared by adulthood although synergistic effects of FSHR and AR knockout were seen. Conclusions: These studies have identified the Sertoli cell-specific transcriptome in the mouse testis and have shown that most genes in the transcriptome are FSH- and androgen-dependent at puberty although the importance of FSH diminishes towards adulthood. [ABSTRACT FROM AUTHOR]

FSH and androgen act to stimulate and maintain spermatogenesis. FSH acts directly on the Sertoli cells to stimulate germ cell number and acts indirectly to increase androgen production by the Leydig cells. In order to differentiate between the direct effects of FSH on spermatogenesis and those mediated indirectly through androgen action, we have crossed hypogonadal (hpg) mice, which lack gonadotrophins, with mice lacking androgen receptors (AR) either ubiquitously (ARKO) or specifically on the Sertoli cells (SCARKO). These hpg.ARKO and hpg.SCARKO mice were treated with recombinant FSH for 7 days and testicular morphology and cell numbers were assessed. In untreated hpg and hpg.SCARKO mice, germ cell development was limited and did not progress beyond the pachytene stage. In hpg.ARKO mice, testes were smaller with fewer Sertoli cells and germ cells compared to hpg mice. Treatment with FSH had no effect on Sertoli cell number but significantly increased germ cell numbers in all groups. In hpg mice, FSH increased the numbers of spermatogonia and spermatocytes, and induced round spermatid formation. In hpg.SCARKO and hpg.ARKO mice, in contrast, only spermatogonial and spermatocyte numbers were increased with no formation of spermatids. Leydig cell numbers were increased by FSH in hpg and hpg.SCARKO mice but not in hpg.ARKO mice. Results show that in rodents 1) FSH acts to stimulate spermatogenesis through an increase in spermatogonial number and subsequent entry of these cells into meiosis, 2) FSH has no direct effect on the completion of meiosis and 3) FSH effects on Leydig cell number are mediated through interstitial ARs. [ABSTRACT FROM AUTHOR]

Background: Monitoring adherence to the Norwegian food-based dietary guidelines (FBDGs) could provide valuable insight into current and future diet-related health risks. This study aimed to develop and evaluate an index measuring adherence to the Norwegian FBDGs to be used as a compact tool in nutrition surveillance suitable for inclusion in large public health surveys., Methods: The Norwegian Dietary Guideline Index (NDGI) was designed to reflect adherence to the Norwegian FBDGs on a scale from 0-100, with a higher score indicating better adherence. Dietary intakes were assessed through 19 questions, reflecting 15 dietary components covered by the Norwegian FBDGs. The NDGI was applied and evaluated using nationally representative dietary data from the cross-sectional web-based Norwegian Public Health Survey which included 8,558 adults.​ RESULTS: The population-weighted NDGI score followed a nearly normal distribution with a mean of 65 (SD 11) and range 21-99. Mean scores varied with background factors known to be associated with adherence to a healthy diet; women scored higher than men (67 vs. 64) and the score increased with age, with higher educational attainment (high 69 vs. low 64) and with better self-perceived household economy (good 67 vs. restricted 62). The NDGI captured a variety of dietary patterns that contributed to a healthy diet consistent with the FBDGs., Conclusion: The NDGI serve as a compact tool to assess and monitor adherence to the Norwegian FBDGs, to identify target groups for interventions, and to inform priorities in public health policies.​ The tool is flexible to adjustments and may be adaptable to use in other countries or settings with similar dietary guidelines., (© 2024. The Author(s).)

Luteinizing hormone (LH) is a key regulator of male fertility through its effects on testosterone secretion by Leydig cells. Transcriptional control of this is, however, currently poorly understood. Mice in which the LH receptor is knocked out (LuRKO) show reduced testicular size, reduced testosterone, elevated serum LH, and a spermatogenic arrest that can be rescued by the administration of testosterone. Using genome-wide transcription profiling of LuRKO and control testes during postnatal development and following testosterone treatment, we show that the transcriptional effects of LH insensitivity are biphasic, with an early testosterone-independent phase and a subsequent testosterone-dependent phase. Testosterone rescue re-enables the second, testosterone-dependent phase of the normal prepubertal transcription program and permits the continuation of spermatogenesis. Examination of the earliest responses to testosterone highlights six genes that respond rapidly in a dose-dependent fashion to the androgen and that are therefore candidate regulatory genes associated with the testosterone-driven progression of spermatogenesis. In addition, our transcriptional data suggest a model for the replacement of fetal-type Leydig cells by adult-type cells during testicular development in which a testosterone feedback switch is necessary for adult Leydig cell production. LH signaling affects the timing of the switch but is not a strict requirement for Leydig cell differentiation.

Androgens act to stimulate spermatogenesis through androgen receptors (ARs) on the Sertoli cells and peritubular myoid cells. Specific ablation of the AR in either cell type will cause a severe disruption of spermatogenesis. To determine whether androgens can stimulate spermatogenesis through direct action on the peritubular myoid cells alone or whether action on the Sertoli cells is essential, we crossed hypogonadal (hpg) mice that lack gonadotrophins and intratesticular androgen with mice lacking ARs either ubiquitously (ARKO) or specifically on the Sertoli cells (SCARKO). These hpg.ARKO and hpg.SCARKO mice were treated with testosterone (T) or dihydrotestosterone (DHT) for 7 d and testicular morphology and cell numbers assessed. Androgen treatment did not affect Sertoli cell numbers in any animal group. Both T and DHT increased numbers of spermatogonia and spermatocytes in hpg mice, but DHT has no effect on germ cell numbers in hpg.SCARKO and hpg.ARKO mice. T increased germ cell numbers in hpg.SCARKO and hpg.ARKO mice, but this was associated with stimulation of FSH release. Results show that androgen stimulation of spermatogenesis requires direct androgen action on the Sertoli cells.

Development and maintenance of the male phenotype and establishment of fertility are all dependent upon the activity of the Sertoli cells and Leydig cells of the testis. This review examines the regulation and function of these cell during fetal and post-natal development. Fetal Leydig cells are sensitive to both luteinising hormone (LH) and adrenocorticotrophic hormone (ACTH) but Leydig cell function appears normal in fetal mice lacking both hormones or their receptors. Post-natally, the Sertoli cells and Leydig cells are reliant upon the pituitary gonadotrophins. Leydig cells are critically dependent on LH but follicle-stimulating hormone (FSH), presumably acting through the Sertoli cell, can also affect Leydig cell function. Testosterone secreted by the Leydig cells acts with FSH to stimulate Sertoli cell activity and spermatogenesis. Study of animals lacking FSH-receptors and androgen-receptors shows that both hormones can act to maintain the meiotic germ cell population but that androgens are critical for completion of meiosis.

FSH acts through the Sertoli cell to ensure normal testicular development and function. To identify transcriptional mechanisms through which FSH acts in the testis, we have treated gonadotrophin-deficient hypogonadal (hpg) mice with recombinant FSH and measured changes in testicular transcript levels using microarrays and real-time PCR 12, 24 and 72 h after the start of treatment. Approximately 400 transcripts were significantly altered at each time point by FSH treatment. At 12 h, there was a clear increase in the levels of a number of known Sertoli cell transcripts (e.g. Fabp5, Lgals1, Tesc, Scara5, Aqp5). Additionally, levels of Leydig cell transcripts were also markedly increased (e.g. Ren1, Cyp17a1, Akr1b7, Star, Nr4a1). This was associated with a small but significant rise in testosterone at 24 and 72 h. At 24 h, androgen-dependent Sertoli cell transcripts were up-regulated (e.g. Rhox5, Drd4, Spinlw1, Tubb3 and Tsx) and this trend continued up to 72 h. By contrast with the somatic cells, only five germ cell transcripts (Dkkl1, Hdc, Pou5f1, Zfp541 and 1700021K02Rik) were altered by FSH within the time-course of the experiment. Analysis of canonical pathways showed that FSH induced a general decline in transcripts related to formation and regulation of tight junctions. Results show that FSH acts directly and indirectly to induce rapid changes in Sertoli cell and Leydig cell transcript levels in the hpg mouse but that effects on germ cell development must occur over a longer time-span.

Female mice in which the gene encoding the follicle-stimulating hormone FSH receptor (FSHR) knockout (KO) or its ligand (FSHbetaKO) have been disrupted were infertile. Ovaries of these mice were significantly smaller than those of heterozygous littermates but significantly larger than those of hypogonadal mice of the same age. Uterine masses in all three mutants were <6 mg, significantly reduced compared with heterozygous mice. At 1 year of age uterine mass had increased to >12 mg in 63% of FSHRKO females and 88% of FSHbetaKO females. Despite the increase in uterine size there was no evidence of contractility: uteri were flaccid and unresponsive to electrical or pharmacological stimulation. In most females in which uterine growth had occurred there was evidence of ovarian growth with hypertrophy of the interstitial tissue, occurrence of ovarian cysts and epithelial and tubular inclusions. There was no evidence of uterine or ovarian hypertrophy in hypogonadal (hpg) mice at any age or in 1 year old females in which the FSH mutations were bred onto the hpg background. There was an inverse correlation of plasma LH concentrations and uterine mass in 1 year old mutant females with uterine hypertrophy. Ovariectomy of both FSHRKO and FSHbetaKO females with large uteri resulted in decreased uterine mass and increased plasma concentration of LH. The number of mice with ovarian pathology, reminiscent of the serous ovarian adenocarcinomas found in humans, was significantly greater in the FSHbetaKO mice, indicating that the presence of an intact FSH receptor on ovarian cells of FSHbetaKO females may allow constitutive basal stimulation of the ovary, which is absent in mice lacking FSH receptors.

To investigate further brain-pituitary-gonadal interrelationships we have generated mice in which the gene encoding the FSH receptor has been disrupted. Female FSH receptor knockout (FSHRKO) mice were infertile. The ovaries were significantly reduced in size, with follicular development arrested at the preantral stage, but there was evidence of stromal hypertrophy. The vagina was imperforate, and the uterus was atrophic. There was no response to administration of PMSG. Inhibins A and B were undetectable in both the serum and gonads. Compared with those in control animals, serum concentrations of FSH and LH were significantly elevated in mutant females. The pituitary content of FSH, but not LH, was also significantly elevated. Estrogen administration in FSHRKO female mice suppressed serum LH levels to those seen in control mice, whereas FSH levels were reduced by only 50%. Male FSHRKO mice were fertile, although testis weight was significantly reduced. However, testicular inhibin A and B concentrations did not differ from those in normal littermates. Serum levels of FSH and LH were elevated in the null mutant male mice, whereas no differences were found in the pituitary content of these hormones. In conclusion, ovarian follicular development cannot progress beyond the preantral stage without FSH. In the absence of mature follicles ovarian estrogen remains low, and consequently accessory sex tissue growth and negative feedback regulation of gonadotropin secretion are severely compromised. In the male, however, inability to respond to FSH does not impair fertility, although testicular weight is reduced, and feedback regulation of pituitary gonadotropins and intratesticular paracrine interactions may be disturbed.

This study is an examination of the interaction of humor and gender in moderating relationships among perceived stress, anxiety, and physical symptoms. Introductory psychology students (70 women, 61 men) completed self-report scales measuring perceived stress, humor, and symptomology. Multiple regression analyses revealed a moderating effect for humor between stress and anxiety, but only for men. When humor was low, a positive relationship was obtained between stress and anxiety; no relationship existed when humor was high. No gender differences were found in the significant moderating effect of humor between stress and physical symptoms. When humor was low, stress was related to physical symptoms; no relationship was found when humor was high. Overall, the findings supported humor as a moderator of stress; gender differences also existed for some outcomes.

The effects of traditional risk factors on low birth weight were examined, using logistic regression analyses and adjusting for interactions between multiple factors. Data for 11,936 births were obtained from a state birth cohort file. The effect for maternal ethnicity was dependent on education and marital status; the effect of marital status was dependent on ethnicity, medical risk, and level of prenatal care; and the effect of prenatal care was dependent on marital status. Results suggest that examining only main effects and ignoring interactions can produce overgeneralized conclusions about the influence of individual risk factors on low birth weight.

Self-esteem was explored as a factor in appropriate (typical) and inappropriate (atypical) changes in performance expectations across trials of a nonthreatening success condition vs. a threatening failure condition. Participants (51 women, 45 men) were randomly assigned to one of the conditions and completed a self-esteem scale and 8 trials of a timed digit-substitution task. Moderated multiple regression revealed significant interactions between self-esteem and condition for typical and atypical changes. A significant positive relationship between self-esteem and typical changes was found under success and between self-esteem and atypical changes under failure. Differences between conditions were evident only for high self-esteem, with greater typical changes for success and greater atypical changes for failure.

This study examined the effects of traditional risk factors on receipt of inadequate prenatal care when controlling for interactions of multiple factors. Birth certificate data on 11,936 births were obtained from a state birth cohort file. A logistic regression model indicated significant interactions between maternal ethnicity (black vs white), marital status, and education in the prediction of inadequate prenatal care. Examining only main effects and ignoring interactions can produce oversimplified conclusions about individual risk factors.

Relationships between perceived stress, self-esteem, and expectancy of success were examined, and the moderating and mediating effects of self-esteem between perceived stress and expectancy of success were explored. Participants (48 women, 27 men) completed self-rating scales measuring perceived stress, self-esteem, and expectancy of success. Negative relationships were obtained between perceived stress and self-esteem and between perceived stress and expectancy of success. Self-esteem and expectancy of success were positively associated. Moderated multiple regression analysis yielded no moderating effect of self-esteem between perceived stress and expectancy of success; however, a moderating effect of self-esteem was obtained using regression techniques.

The National Institute on Alcohol Abuse and Alcoholism, in consultation with the National Institute on Drug Abuse, awarded nine demonstration grants in 1988 for community-based programs addressing issues of the homeless alcohol and other drug (AOD) abusers. Project Connect in Louisville, Kentucky, was one of the nine demonstration grants. The three-year project was designed to address a multitude of needs of the homeless male AOD abuser, including housing, medical, employment/economic, and social support, in addition to treatment for AOD abuse. The present article details the evolution and implementation of Project Connect and describes characteristics of the target population. In addition, the article presents issues and problems that surfaced during program implementation in order to assist other communities that are considering similar programs for their homeless populations.

THe main metabolite of prostaglandin E2 (PGE2) 13,14-dihydro-15-keto-PGE2 readily dehydrates and can subsequently form a cyclic derivative. This problem can be overcome by the immediate formation of oximes of the 9 and 15 ketones in aqueous solution followed by subsequent extraction, methylation and t-butyldimethyl silylation of the free hydroxyl groups at 11 and on the oximes. Deuterogenated 13,14-dihydro-15-keto-PGE2 is used as the internal standard and can be stored as the oxime and added with the oximating solution immediately the biological sample is obtained. The sensitivity of the method allows measurement of 2 ng of 13,14-dihydro-15keto-PGE2 in tissue incubates. The intra-batch precision is 11.8% and the inter-batch precision for measurement of 100 ng of metabolite is 8.1%.

We have tested the action of a catechol oestrogen -2,3,17 beta-trihydroxy oestra-1,3,5 (10)-triene (2-OH oestradiol) in stimulating prostaglandin (PG) production by an homogenate of rat uterus. Marked and dose dependent stimulation was observed in PGF2 alpha and PGE2 production using 20-250 microM concentrations of catechol oestrogen; a concentration of 250 microM 2-OH oestradiol resulted in a 23 fold increase in PGF2 alpha production with a 50% reduction in the synthesis of 6-keto PGF1 alpha. Tryptophan, catechol and glutathione were without effect on PGF2 alpha and PGE2 production whereas adrenalin stimulated the production of all PGs, although the increase was less than that seen with 2-OH oestradiol. Oestradiol had a slight stimulatory action on PGF2 alpha production which reached a maximum at around 40 microM but had a more marked stimulation of 6-keto PGF1 alpha formation. Stimulation of prostaglandin production by oestradiol and 2-OH oestradiol showed no variation at different stages of the rat oestrous cycle. The use of 5 to 100 mg of tissue/ml gave similar product distribution although the effect of catechol oestrogen both in terms of stimulation of E and F formation (expressed per mg of tissue) and in its action on product distribution was more marked at lower concentrations of tissue.

The ovariectomized, oestrogen-treated, late pregnant rat has been used to compare the ability of two calcium antagonists, diltiazem and nifedipine, with an agonist at beta-adrenoceptors, salbutamol, to prevent the development of uterine contractions, prolong gestation and maintain fetal survival in utero. Preterm delivery of the fetuses was not prevented in the animals infused with salbutamol (2 micrograms/kg/min), occurring at the same time, 30-40 h after ovariectomy, as in the saline-infused rats. The overall integral of uterine contractions was significantly reduced in the salbutamol-treated compared with the saline-treated animals due to decreased contractions after abortion. Both diltiazem (100 micrograms/kg/min) and nifedipine (3.1 and 6.2 micrograms/kg/min) produced significant inhibition of uterine contractions and in contrast to salbutamol prolonged gestation and improved fetal survival in utero as assessed at post mortem on Day 21. However, maternal survival was low (57%) with the higher dose of nifedipine, possibly reflecting the relaxant effect of this compound on vascular smooth muscle with consequent underperfusion of vital organs.

The pattern of prostaglandins (PGs) synthesized by persistent proliferative endometrium of women with excessive menstrual bleeding (greater than 50 ml) associated with anovulatory cycles was compared to endometrium collected from women with normal menstrual blood loss (less than 50 ml). Levels of PGF2 alpha in normal and persistent proliferative endometrium were lower than the levels of PGF2 alpha found in normal secretory endometrium (P less than 0.005 for both normal and persistent proliferative endometria). When incubated with exogenous [1-14C]arachidonic acid (9.1 nmol), normal secretory endometrium synthesized more PGF2 alpha and PGE2 than did normal proliferative endometrium, but the amounts of PGF2 alpha and PGE2 released by persistent proliferative endometrium were similar to those obtained by normal secretory endometrium. These findings suggest that persistent proliferative and normal secretory endometria have the same PG synthetase activity, and that the low endogenous concentrations of PGF2 alpha in the former arise from a lack of endogenous precursor. PGF2 alpha has predominantly vasoconstricting properties, and a reduced capacity to synthesize this PG by persistent proliferative endometrium may result in excessive menstrual bleeding, as was suggested by the inverse correlation between the ratio of the endogenous concentrations of PGF2 alpha and PGE and the menstrual blood loss (r = -0.7; P less than 0.005; n = 26).

The potencies of four calcium antagonists (nifedipine, gallopamil, verapamil and diltiazem) at inhibiting uterine contractions in vivo have been assessed in the conscious ovariectomized, post-partum rat. Their selectivities for this action, relative to their effects on blood pressure and heart rate, have been compared with salbutamol. All compounds produced a dose-dependent inhibition of intra-uterine pressure cycles. The rank order of potency was salbutamol greater than nifedipine greater than diltiazem = gallopamil greater than verapamil. All compounds produced a dose-dependent fall of mean blood pressure. The rank order of potency was salbutamol greater than nifedipine greater than gallopamil greater than verapamil greater than diltiazem. Salbutamol and nifedipine produced a tachycardia, which was very marked with salbutamol. Gallopamil, verapamil and diltiazem induced a moderate tachycardia at low doses but temporary cessation of heart beat occurred at high doses. Nifedipine and diltiazem, like salbutamol, exhibited some selectivity for inhibition of uterine contractions relative to their cardiovascular actions. Gallopamil and verapamil showed no selectivity for the uterus.

17 beta-estradiol and progesterone were administered to post-menopausal women to determine their effects in vivo on the capacity of human endometrium to synthesize prostaglandins (PGs) F2 alpha and E. Basal amounts of PGF2 alpha and PGE synthesized by endometrium exposed to 17 beta-estradiol and progesterone were significantly higher than the levels produced by endometrium exposed to 17 beta-estradiol alone (p less than 0.02 for both PGs). Levels found in the former endometrium were broadly comparable to levels in secretory endometrium and in the latter to amounts found in proliferative endometrium of spontaneous, ovulatory cycles.

Concentrations of prostaglandin F2 alpha (PGF2 alpha) and prostaglandin E (PGE) were measured in endometrium from 18 women with ectopic pregnancies. In the nine pregnancies not associated with vaginal bleeding or an intra-uterine contraceptive device (IUCD; intact ectopics), concentrations of PGF2 alpha (12.8 +/- 7.4 (S.E.M.) ng/g) and PGE (4.7 +/- 3.0 ng/g) were similar to those in decidua from nine intra-uterine pregnancies of comparable gestational age (14.4 +/- 4.4 and 8.2 +/- 2.2 ng/g respectively). In both ectopic and intra-uterine pregnancies concentrations of prostaglandins were significantly lower than those found in endometrium throughout the normal menstrual cycle (P < 0.01). In nine ectopic pregnancies with associated vaginal bleeding and/or an IUCD, concentrations of PGF2 alpha and PGE were significantly higher than in the intact group (P < 0.05), although the concentration of PGF2 alpha remained significantly lower than levels in normal secretory endometrium (P < 0.05). These results suggested that suppression of endometrial synsthesis of prostaglandin during early pregnancy may be mediated systemically rather than through a local action of the conceptus.

The sensitivity of the uterus to the inhibition of contractions by salbutamol, diltiazem or nifedipine was assessed in the ovariectomized, post-partum rat by dose-response curves following bolus intravenous (i.v.) administration. These tests were performed before (day 1), immediately after a 20 h i.v. infusion of salbutamol, diltiazem, nifedipine or appropriate control infusate (day 2) and after a further 20 h infusion of saline (day 3). In a further group of animals sensitivity to nifedipine was assessed before and after a 20 h infusion of salbutamol. Uterine contractions were monitored throughout infusions. Infusion of salbutamol (2 micrograms kg-1 min-1) produced an initial marked inhibition of uterine contractions, an effect which was not maintained despite continued infusion. Contractions reappeared after 2 h of infusion and reached pre-infusion levels by 5 h. The dose-response curve to salbutamol on day 2 was shifted more than 100 fold to the right compared with that on day 1. Sensitivity of the uterus on day 3 did not differ from that on day 1. Nifedipine (25 micrograms kg-1 min-1) produced sustained inhibition of uterine contractions throughout the 20 h of infusion. Sensitivity of the uterus to nifedipine could not, therefore, be tested on day 2; sensitivity on day 3 did not differ from that on day 1. In addition, there was no change in sensitivity of the uterus to nifedipine after a 20 h infusion of salbutamol. 4 Diltiazem (200 Ig kg-' min-') produced a marked initial inhibition of uterine contractions, with a partial return of contractions during continued infusion in 7 out of 12 animals so that mean integral values reached 40% of those pre-infusion. The dose-response curve to diltiazem on day 2 showed a 25 fold shift to the right compared with that on day 1 in 4 out of 12 animals where the test could be performed. Sensitivity of the uterus on day 3 did not differ from that on day 1. 5 These findings suggest that marked but reversible tolerance to the inhibitory actions of salbutamol on uterine contractions occurs during long-term infusion. There was no evidence of tolerance to the uterine actions of nifedipine, but there was evidence of tolerance to diltiazem in some animals.

In this study we have obtained endometrium and myometrium from women whose menstrual blood loss had been measured objectively. Samples of tissue were snap frozen in liquid nitrogen for the estimation of PG content and tissue was homogenized and incubated with and without added arachidonic acid. PGE, PGF2 alpha and 6-oxo PGF1 alpha were measured by gas chromatography - mass spectometry. We confirm that the F2 alpha/E2 ratio in the snap frozen samples was significantly lower in women with a high blood loss although this was not reflected in the production by incubated homogenates. Incubation of endometrial tissue with myometrium from the same patient and with a pool of myometrium showed that the source of myometrium was not important. This suggests that previous observations of increased 6 oxo F1 alpha production in incubations of endometrium and homologous myometrium from women with high MBL, resulted from differences in endometrium. When prostaglandin E and F production by endometrium is studied there is a significant inverse correlation between the percentage difference in production with and without added arachidonic acid and menstrual blood loss which suggests that women with high MBL have relatively high levels of available arachidonic acid in their endometrium.

Prostaglandins (PGs) have often been cited as intermediates in the action of the inert and copper-bearing intrauterine contraceptive device (IUD). Although investigations have shown an effect of copper at high (approx. 1 x 10(-4) mol/l) concentrations on PG synthesis, little consideration has been given to the possible effects of copper on PG metabolism. In this study the effect of copper and zinc ions on PG metabolism by human endometrium and myometrium has been investigated using radiolabel techniques together with gas chromatography mass spectrometry (GCMS) measurements of metabolites of PGE2. These experiments showed that concentration of 1 X 10(-5) mol/l of copper and zinc were sufficient to inhibit significantly (P less than 0.01) PGE metabolism. These levels of copper are within the physiological range of levels thought to be present in the uterine tissue and fluid of wearers of the copper-containing IUD and the inhibition of PG metabolism in these women might account for the small but significant decrease in the length of the luteal phase of their menstrual cycles.

Endometrium collected from 18 normal women at various stages of the menstrual cycle was maintained in organ culture for periods of 6 days. Both prostaglandin F2 alpha (PGF2 alpha) and PGE were detected in medium from late proliferative (days 10-14; n = 13) and late secretory (days 20-26; n = 5) endometria cultured in the absence of exogenous steroids. During the first 48 h in culture, the output of PGF2 alpha by secretory endometrium was significantly greater than that of proliferative tissue. The addition of 17 beta-estradiol to the culture medium at doses ranging from 1.0-100.0 ng/ml induced a significant increase in the output of PGF2 alpha by secretory but not proliferative endometria. The addition of progesterone at doses ranging from 5.0-500.0 ng/ml significantly reduced the output of PGF2 alpha and PGE by both proliferative and secretory endometria and prevented the 17 beta-estradiol-stimulated increase in PGF2 alpha output by secretory tissue.

We investigated the ability of the nonpregnant human uterus to metabolize prostaglandins E2 and F2 alpha (PGE2 and PGF2 alpha) using radiolabeled substrates together with gas chromatography-mass spectrometry for the measurement of specific metabolites. Both the 15-hydroxyprostaglandin dehydrogenase and the delta 13-reductase enzymes are present in endometrium and myometrium. As shown for other tissues, the dehydrogenase is NAD+ dependent, while the delta 13-reductase requires NADPH as cofactor. PGE2 was the preferred substrate in both tissues; however, the metabolizing capacity of follicular phase myometrium was comparable with that of midluteal phase endometrium. The Km values of the dehydrogenase for PGE2 and PGF2 alpha were similar in both endometrium (1.89 X 10(-6) and 18.52 X 10(-6) mol/liter, respectively) and myometrium (2.76 X 10(-6) and 11.64 X 10(-6) mol/liter, respectively), suggesting that the same enzyme is present in both tissues although the regulation of this enzyme may differ in endometrium and myometrium.

A detailed description is given of a method to section the pituitary stalk of the fetal lamb after 105 days gestational age. The approach to the stalk is made through a window in the frontal bone. In order to prevent regeneration of the hypothalamo-pituitary connections a silicone plate is introduced through the probe used to fracture the stalk. The surgical outcome and viability of 11 pituitary stalk sectioned fetuses is described over periods of up to 23 days. The presence of pituitary infarction following stalk section was related to damage of the anterior hypophysial vesssels if the probe was deviated from the mid-line at any time in its course. The effect of this procedure on fetal plasma T4 and PRL concentrations and the initiation of premature labour by the continuous infusion of cortisol into the fetus is described.

The concentrations of PGF2 alpha, PGE2 and 6-oxo-PGF1 alpha were measured in human uterine tissues during the menstrual cycle. The concentrations of all PGs in endometrium were greater than in myometrium. PGF2 alpha, which was found in the greatest concentrations, was high in the mid-secretory phase in both endometrium and myometrium. The concentration of PGE2 did not vary during the menstrual cycle in either tissue. The biosynthetic capacity of endometrium to produce both PGF2 alpha and PGE2 was significantly greater in the mid than the late secretory phase in the presence of exogenous arachidonic acid. Also, in spite of low endogenous concentrations, both endometrium and myometrium were able to produce significant amounts of 6-oxo-PGF1 alpha during a 30 minute incubation. The possible significance of this late secretory decline in the capacity of the endometrium to produce PGF2 alpha and PGE2 is discussed.

The endogenous concentrations of prostaglandins F2 alpha (PGF 2 alpha) and E (PGE) were measured during the luteal phase of the menstrual cycle in the endometrium from 14 women with unexplained menorrhagia (measured menstrual blood loss in excess of 50 ml) and 15 women with normal menses (blood loss 50 ml or less). Although there was no significant difference in the PGF 2 alpha/PGE ratio between the two groups, this ratio was significantly lower in the endometrium from eight of the women whose blood loss exceeded 90 ml (p less than 0.05). There was a significant inverse correlation between the PGF 2 alpha/PGE ratio and blood loss (r = 0.36, p less than 0.025). The synthetic capacity of the endometrium was assessed by incubation of the tissue with 14C arachidonic acid. Endometria from nine women with unexplained menorrhagia synthesized more PGE2 than PGF 2 alpha, whereas the converse was true with 11 control endometria. Consequently the PGF2 alpha/PGE2 ratio was significantly reduced in the former group (p less than 0.025). Oestradiol-17 beta (200 microM) and to a greater extent 2 hydroxy oestradiol (200 microM) increased the total prostaglandin synthesis by the endometria, but did not significantly alter the PGF2 alpha/PGE2 ratio. These results suggest that excessive blood loss may be associated with a shift in the endometrial conversion of prostaglandin endoperoxide from PGF2 alpha to PGE2.