Time-related changes in the plasma concentrations of prolactin, gonadotropins, sex hormone-binding globulin, and certain steroid hormones in female runners after a long-distance race.

Running is associated with an increase in plasma concentrations of certain anterior pituitary hormones and adrenal steroids. This study reports such increases after a marathon race. Six trained female runners, 26 to 42 years old, participated in a marathon race. Fasting (resting) blood samples were collected a few weeks before the race (baseline) and immediately (0 hour), 1 hour, and 4 hours after the run. The data were analyzed with the use of two-way analyses of variance (F-test), paired t-test, and Page's test. At 0 hour, compared with baseline, significant increases were observed in the plasma concentrations of testosterone (T), dehydroepiandrosterone sulfate (DHEA-S), cortisol (F), free T index (T/SHBG), and prolactin (PRL). At 1 hour, levels of these steroid hormones and PRL declined, some significantly. At 4 hours, levels of all hormones except DHEA-S returned to baseline. No significant changes were observed in concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and sex hormone-binding globulin (SHBG), as evaluated by F-test. Running-associated changes in plasma hormonal concentrations revert to baseline in four hours, although DHEA-S may take a little longer.

Luteinized unruptured follicle syndrome in mild endometriosis. Assessment with biochemical parameters.

Failure to extrude an ovum, with subsequent luteinization of the unruptured follicle (LUF), has been proposed as a cause of infertility in women with mild endometriosis. To assess the incidence of this process we performed laparoscopies in the early luteal phase on 16 women with mild endometriosis and 8 control subjects. Peritoneal fluid was aspirated and a plasma sample obtained concurrently. Estradiol (E2) and progesterone (P) concentrations were determined. A review of the literature suggested that the following hormonal criteria correlated with follicular rupture: fluid E2 greater than or equal to 500 pg/ml, E2 fluid/plasma ratio greater than or equal to 3.1, fluid P greater than or equal to 3,000 ng/dl and P fluid/plasma ratio greater than or equal to 5:1. All control subjects met at least one E2 and one P criterion: 75% met all. In contrast, less than one-third with mild endometriosis met all, and three (19%) met none. Five met only E2 criteria. These findings suggest that LUF occurs occasionally in association with mild endometriosis. Additionally, ovarian steroidogenesis, particularly P secretion, was impaired frequently in the absence of LUF in women with endometriosis.

The effect of estrogen treatment on plasma concentrations of steroid hormones, gonadotropins, prolactin and sex hormone-binding globulin in post-menopausal women.

Twenty-one post-menopausal women on no other medication were treated with a low dose (0.625 mg/day) of conjugated equine estrogen (CEE) for a mean (+/- SEM) period of 2.6 +/- 0.2 mth (range 1.75-4.75). Blood samples were collected before and at the completion of therapy, and alterations in the levels of prolactin (PRL), follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG) and certain steroid hormones, including the free testosterone (T) index (T/SHBG) were studied. Following treatment, a significant increase in SHBG levels produced a significant decrease in the free T index (P less than 0.005). As expected, no changes were observed in the levels of PRL and steroid hormones other than estrone (E1) and estradiol-17-beta (E2). Our observations indicate that treatment of post-menopausal women with low-dose estrogen lowers the unbound T.

Vasoactive intestinal polypeptide stimulates nonovarian progesterone secretion in rabbits.

Recent experiments conducted in this laboratory have shown that intravenous infusions of vasoactive intestinal polypeptide (VIP) induced significant increases in plasma progesterone (P) in female rabbits. The purpose of this study was to determine the organ source of this P and to clarify the mechanisms by which it is induced. Intravenous infusions of VIP (37.5, 75, and 150 pmol/kg per min for 60 min) produced acute dose-dependent increases in plasma P in intact estrous rabbits. In ovariectomized (OVX) animals, VIP infusion (75 pmol/kg per min) produced a P increase of the same magnitude. In animals both OVX and adrenalectomized (ADX), this VIP effect was eliminated. The only significant change noted in luteotropic hormone (LH) or follicle stimulating hormone (FSH) was a decrease in FSH immediately following VIP infusion (150 pmol/kg). VIP infusion significantly increased plasma cortisol in intact and OVX animals, but not in OVX/ADX animals. It is concluded that VIP primarily stimulates the adrenal component of P secretion in the rabbit, via mechanisms independent of LH or FSH.

Effects of vasoactive intestinal polypeptide upon ovarian steroids, ovum transport and fertility in the rabbit.

The purpose of this study was to determine the effects of infused vasoactive intestinal polypeptide (VIP) upon reproductive function in the female rabbit. Intravenous infusions of VIP (37.5, 75, and 150 pmol/kg per min) induced acute dose-dependent increases in plasma progesterone (P) but not estradiol (E2) or testosterone (T) in estrous rabbits. This P effect was not associated with an increase in plasma prolactin (Prl) and was not altered by pretreatment with a Prl-inhibiting regimen of bromocriptine. In rabbits stimulated to ovulate with 75 IU human chorionic gonadotropin (hCG) and coitus, plasma P and E2 increased, reaching a peak at 180 min following stimulation. VIP (75 pmol/kg per min) infused from 120 to 180 min following the ovulatory stimuli increased this P peak but did not effect E2 levels. This VIP infusion had no effect upon fertility or upon the number of corpora lutea, uterine implants, or viable conceptuses. Infusions of VIP for 60 min at the P peak, and for 240 min at the time of ovulation, had no significant effect upon ovum pickup or the rate of ovum transport. These observations suggest that 1) VIP infusions in rabbits can increase plasma P from both the basal levels of estrus and from the peak levels preceding ovluation. 2) Infusions of VIP at the time of the preovulatory steroid surge or during ovulation have little effect upon fertility or gamete transport in the rabbit. 3) Endogenous VIP may play a role in the regulation of P secretion in the rabbit.

Sex-hormone-binding globulin in clinically hyperandrogenic women: association of plasma concentrations with body weight.

The relationship of sex-hormone-binding globulin (SHBG) with actual body weight (ABW), ideal body weight (IBW), ABW as percentage of the IBW (% IBW), Quetelet index (weight/height2) and plasma concentrations of various androgens and 17 beta-estradiol (E2) were studied in 9 normal and 57 hirsute patients (group 1). In hirsute patients, plasma levels (ng/dl, mean +/- standard error of the mean [SEM]) of testosterone (T; 77 +/- 4), dihydrotestosterone (DHT; 26 +/- 2), androstenedione (delta 4A; 184 +/- 16), and SHBG (0.91 +/- 0.05 micrograms DHT/dl) but not of dehydroepiandrosterone (DHA; 608 +/- 55) and E2 (6.1 +/- 0.1) were significantly different from those in controls. A negative correlation was observed between SHBG and ABW, both in controls (P less than 0.05) and hirsute patients (P less than 0.01). The hirsute patient population was subdivided into two groups: nonobese (group 2; 60 +/- 1 kg; n = 35) and obese (group 3; 96 +/- 2 kg; n = 22). Plasma androgens, T/SHBG (an index of free T) and E2 in groups 2 and 3 (T: 75 +/- 4, 81 +/- 7; DHT: 24 +/- 2, 28 +/- 3; T/SHBG: 85 +/- 7, 105 +/- 11; delta 4A: 203 +/- 13, 155 +/- 16; DHA: 663 +/- 83, 521 +/- 49; E2: 6.1 +/- 1.0, 5.8 +/- 0.9) were similar; yet SHBG in group 3 (0.75 +/- 0.04) was significantly lower than in group 2 (1.0 +/- 0.01). Inverse correlations between SHBG and ABW, % IBW, and ABW/H2 were observed in group 2 but not in group 3. We conclude that a negative relationship exists between SHBG and the body size in nonobese women and that in hirsute patients, obesity leads to a further lowering of SHBG through mechanism(s) probably independent of androgens.

Plasma gonadotropins, prolactin, and steroid hormone concentrations in female runners immediately after a long-distance run.

Six normally menstruating women who regularly run participated in a 10-mile race. Blood samples were collected within 20 minutes after the completion of the race (group 1). Samples were analyzed, and the results were compared with plasma hormonal concentrations in the same runners in samples collected between 12 and 24 hours after a previous practice run (group 2) and with our nonathletic female controls. Plasma concentrations of the following hormones in group 1 were significantly elevated when compared with group 2: dehydroepiandrosterone (DHA), androstenedione (delta 4A), testosterone (T), cortisol (F), luteinizing hormone (LH), and prolactin (PRL). Levels of 17 beta-estradiol (E2), 17-hydroxyprogesterone (17-OHP), dehydroepiandrosterone sulfate (DHAS), and follicle-stimulating hormone (FSH) were comparable in groups 1 and 2. However, DHAS in group 1 was elevated when compared with controls, as were HDA, delta 4A,T,F,LH, and PRL. In group 1, but not in group 2, a significant correlation (P less than 0.05) was observed between plasma LH and PRL concentrations but not between FSH an PRL. We conclude that the immediate effect of running is reflected in increased levels of the adrenal androgens, F, LH, and PRL. However, concentrations of these hormones revert back to baseline within 12 to 24 hours after the race.

Plasma androgens, 17 beta-estradiol, and sex hormone-binding globulin in patients with hirsutism and/or clitoromegaly.

Plasma androgen, 17 beta-estradiol, and sex hormone-binding globulin (SHBG) levels were measured in 11 normal subjects (group 1), 18 hirsute patients with no clitoromegaly (group 2), 13 hirsute patients with clitoromegaly (group 3), and 8 patients with clitoromegaly but no hirsutism (group 4). Significantly elevated levels of testosterone (T) and dihydrotestosterone (DHT) were found in groups 2 and 3 but not in group 4 when compared with group 1. In contrast, levels of dehydroepiandrosterone (DHEA) in groups 1 and 2 were comparable but significantly lower than those in group 3 and 4; the levels in the latter two groups were not significantly different from each other. In groups 2, 3, and 4, levels of androstenedione (delta 4A) and the factor T/SHBG were significantly elevated whereas SHBG levels were significantly suppressed when compared with those of group 1. The clitoral index correlated (P less than 0.01) with DHEA levels in group 3. It is concluded that clitoromegaly without hirsutism is associated with increased plasma levels of DHEA and delta 4A. In contrast, hirsutism without clitoromegaly is associated with elevated levels of T, DHT, and delta 4A but normal DHEA levels.

Plasma androgens and sex hormone-binding globulin in the evaluation of hirsute females.

Hirsutism is usually associated with increased testosterone (T) production and metabolic clearance rates. Considerable overlap of plasma T occurs between hirsute and normal groups. Plasma levels of sex hormone-binding globulin (SHBG) and the factor T/SHBG might separate hirsute patients from normal subjects better than plasma T. A group of 39 hirsute females and 22 normal ovulatory control subjects were studied. Plasma T, androstenedione, and dehydroepiandrosterone were measured by radioimmunoassay; apparent free T (AFT) by equilibrium dialysis; and SHGBG by a method based on saturating the binding sites by labeled dihydrotestosterone. Mean levels of androgens and SHBG of the hirsute patients were significantly different from those of the normal subjects (P less than 0.01). Positive linear correlations were observed between T and AFT, T/SHBG and AFT, and T/SHBG and T; a negative correlation was observed between T/SHBG and SHBG, but no correlation was observed between SHBG and T or AFT. Thirty (77%) of the patients had elevated T/SHBG factors and 28 (72%) had suppressed SHBG levels. Only two patients (5%) had hirsutism associated with normal levels of androgens, SHBG, and T/SHBG. We conclude that SHBG and the factor T/SHBG separate the hirsute population better than any of the androgens studied.

Plasma steroid concentrations in maternal and umbilical circulation after spontaneous onset of labor.

Blood samples were obtained from the maternal peripheral vein (n = 17) during the second stage of spontaneous labor and from the umbilical artery (UA) and vein (UVn) immediately after delivery. Four delta 4-and five delta 5-steroids as well as estradiol were measured by RIA. Additionally, cortisol was determined in maternal plasma. The maternal concentrations were compared with our control values obtained from samples (n = 30) collected at term but not in labor. All delta 5-steroids and F were significantly higher during labor than before labor. In the umbilical circulation, progesterone and 17-hydroxyprogesterone were significantly higher in the UVn than in UA (P < 0.05). Whereas androstenedione was significantly higher in the UA [1.01 +/- 0.12 ng/ml (mean +/- SEM)] than in the UVn (0.72 +/- 0.07 ng/ml), testosterone was almost identical in the two (UA, 0.33 +/- 0.03 ng/ml; UVn, 0.35 +/- 0.08 ng/ml). Four of the five delta 5-steroids (dehydroepiandrosterone, dehydroepiandrosterone sulfate, pregnenolone sulfate, and 17-hydroxypregnenolone) had significantly higher concentrations in the UA than in the UVn (P < 0.05). However, pregnenolone levels were not significantly different (UVn, 21.8 +/- 2.0 ng/ml; UA, 18.0 +/- 2.0 ng/ml). No significant correlations were observed between maternal and umbilical steroid concentrations.

Progesterone, 17-hydroxyprogesterone, estradiol, and estriol in late pregnancy and labor.

Levels of progesterone, 17 alpha-hydroxyprogesterone, estradiol, and estriol were measured in serial plasma samples collected from 30 uncomplicated pregnancies during the last eight weeks of gestation. From another group of 27 uncomplicated pregnancies, blood samples were collected during the second stage of labor and the same steroids were measured. Progesterone, 17-hydroxyprogesterone, and estradiol levels were highest during the last one to three weeks prior to the onset of labor, whereas estriol concentration increased progressively. The levels of these steroids during the second stage of labor were statistically not different from those just preceding labor. It is concluded that the onset of human labor is not associated with marked changes in the maternal levels of any of these steroids.