Search PubMed⌕ Search

Biomedical subjects

H L Judd

Publications and source records attributed to H L Judd.

At least 91 records · Page 5Linked to original sources

Estrogen and sex hormone-binding globulin levels in nulliparous and parous women.

The hormone profiles of nulliparous and parous women on day 11 of their menstrual cycle have been studied in an attempt to seek evidence for the hormonal basis of the protective effect of first birth on breast cancer risk. A previous publication reported that there were significantly lower (26%) early morning prolactin levels in parous women as compared to those levels in nulliparous women but that there were no differences in plasma and urinary estrogen levels. The present study shows, however, that parous women had significantly shorter cycle lengths than nulliparous women of the same age, and the data were reevaluated with this difference being taken into account. After adjustment for cycle length (within the range of 24-32 days) and age, estrogen levels were significantly lower (22%) in parous women compared to those in nulliparous women. Two further aspects of estrogen metabolism were measured in the plasma samples of these women: the binding capacity of sex hormone-binding globulin (SHBG) and the percentage of free estradiol (E2). SHBG levels were 12% higher in parous women, but there was no difference in percentage of free E2. In the previous publication it was suggested that the protective effect of first birth on breast cancer risk was mediated in part by permanently lowering prolactin levels. The current findings suggest that changes in estrogen metabolism also are a factor.

Adult↗

Direct action of androgen on hot flushes in the human male.

Hot flushes (HF) were demonstrated definitively in a hypogonadal man by continuous recordings of finger temperature, skin resistance and subjective symptoms. The magnitudes and temporal interrelationships of these physiological changes were similar to those previously observed in oophorectomized women. HF were abolished by injections of methyl testosterone (MT) and during oral administration of fluoxymesterone (FM), a non-aromatizable androgen. Increases of the non-SHBG bound fractions of T and E2 were noted during MT therapy, either of which may have been responsible for suppression of HF. No significant changes of the non-SHBG bound levels of E2 were observed during FM ingestion. These data confirm that typical HF occur in the male and support the concept that androgen acts directly on the central nervous system without requiring aromatization to estrogen in the brain or other tissues.

Adult↗

Prepubertal treatment with estrogen or testosterone precipitates the loss of regular estrous cyclicity and normal gonadotropin secretion in adult female rats.

To examine the effects of prepubertal steroid environment on subsequent estrous cyclicity and gonadotropin secretion, Silastic implants containing 25, 50 or 100% 17 beta-estradiol (E2;n=34), 50% diethylstilbestrol (DES; n=16) or 50% testosterone (T; n=17) were placed into female rats at 12 days of age and removed on the day of vaginal opening (18-24 days of age). At 80 days of age, the percentages of regularly cycling females in the E2-(three groups combined), DES- and T-implanted groups were 59%, 0% and 59%, respectively. By 110 days of age, the percentages were reduced to 24%, 0% and 0%, and at 140 days of age 6%, 0% and 0%, respectively. Many of these females displayed irregular estrous cycles followed by a persistent estrous (PE) state. By contrast, 89% of the control females (blank implants or no implant) maintained regular cycles up to 140 days of age. At 150 days of age, an i.p. injection of gonadotropin-releasing hormone (GnRH; 100 ng/100 g BW) markedly increased serum luteinizing hormone (LH), but not follicle-stimulating hormone (FSH), in intact PE females treated prepubertally with E2 implants. After the test with GnRH, PE rats were ovariectomized (OVX). Thirty days after OVX, similar GnRH administration significantly increased serum levels of both LH and FSH, but these responses were significantly (P less than 0.01) reduced when compared with those in OVX controls. Progesterone administration to estradiol benzoate-primed, acutely (3 days) OVX, or long-term (43 days) OVX-PE females did not increase LH or FSH release. These results indicate that exposure to exogenous estrogen or T prior to puberty precipitates the decline in estrous cyclicity associated with the loss of gonadotropin surge response, presumably due to an alteration in hypothalamic GnRH release.

Animals↗

The effects of naloxone on hot flashes and gonadotropin secretion in postmenopausal women.

Hot flashes have a close temporal relationship with the initiation of LH pulses, suggesting that factors stimulating gonadotropin release are involved in the mechanism of this disturbance. It has been reported that the opiate antagonist naloxone acutely blocked subjective hot flashes, a seemingly paradoxical effect, since the use of this agent in premenopausal women increases the magnitude and frequency of LH pulses. We, therefore, studied the effects of naloxone in 16 postmenopausal women with frequent hot flashes using continuous recordings of finger temperature and skin resistance as objective indices of flushing and perspiration, respectively. After baseline recordings, the subjects were randomized into equal groups, and the recordings were repeated during 8-h infusion of either saline or naloxone (22 micrograms/min). Serum gonadotropin levels were measured at 15-min intervals before and during the last 4 h of the infusion. Naloxone did not change the rate of objectively measured hot flashes, mean serum LH or FSH levels, or the frequencies or amplitudes of gonadotropin pulses. These data suggest that there is a very low input of endogenous opiates on gonadotropin secretion in postmenopausal women and that opioid peptides do not play a role in the initiation of the postmenopausal hot flash.

Aged↗

The incidence of late-onset congenital adrenal hyperplasia due to 21-hydroxylase deficiency among hirsute women.

Late-onset congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is a cause of hirsutism in adult women. Its reported frequency of occurrence in hirsute women has varied from 0-30%, but the number of patients studied was small. To establish the incidence of CAH, 83 unselected hirsute women were studied prospectively with a standard ACTH stimulation test. On the basis of an exaggerated response of serum 17 alpha-hydroxyprogesterone to ACTH, 1 patient with CAH was found, for an incidence of 1.2%. The 95% confidence limits for the incidence of CAH among hirsute women were 0% and 3.4%. Five of seven hirsute women without CAH whose serum 17 alpha-hydroxyprogesterone levels rose above 3 ng/ml in response to ACTH had simultaneous serum progesterone values consistent with recent ovulation. Since routine screening of all hirsute women by means of ACTH stimulation does not appear to be cost effective, reported cases of CAH were reviewed in order to discern potentially helpful clinical clues. Severe hirsutism, virilization, early onset of symptoms, short stature, familial occurrence, and regular menses were identified as the clinical characteristics associated with late-onset CAH.

17-alpha-Hydroxyprogesterone↗

Stimulation of LH fragments with reduced bioactivity following GnRH agonist administration in women.

In eumenorrheic women with endometriosis and in oligo-amenorrheic women with polycystic ovarian disease (PCO), chronic administration of a long-acting GnRH agonist (GnRH-a) reduced the circulating concentrations of estrogens and androgens to levels similar to those of castrated women. The concommittant elevation of LH in both groups suggested that the measured immunoreactive LH had reduced bioactivity. In seven women with endometriosis, bioactive LH (BA LH) measured as the in-vitro secretion of testosterone by dispersed Leydig cells, was significantly (p less than 0.001) reduced from 10.8 +/- 1.2 (SEM) to 4.4 +/- 0.2 mIU/ml at the end of 28 days of GnRH-a therapy. In five women with PCO, BA LH decreased from 44.2 +/- 15.5 to 5.7 +/- 0.6 mIU/ml (p = 0.06). These changes of BA LH appeared to be responsible for the suppression of ovarian androgen secretion during GnRH-a treatment and in turn may have contributed to the profound decreases of estrogen production by reducing the amount of precursor androgen available for aromatization. Free alpha subunit levels increased simultaneously with the decrease of BA LH at the end of therapy, suggesting a post-receptor effect of GnRH-a. Beta subunit levels became undetectable. Cross-reaction of alpha subunit in the RIA for LH was sufficient to only partially account for the LH levels measured. On sephadex G-100 chromatography the excess immunoreactive material was detected at and immediately following the alpha subunit tracer. Further studies will be necessary to elucidate the chemical nature of the immunoreactive LH secreted during GnRH-a therapy.

Endometriosis↗

Further delineation of hypothalamic dysfunction responsible for menopausal hot flashes.

An association exists between pulsatile LH release and hot flashes (HFs). To further delineate the hypothalamic mechanism(s) responsible for HF, the basal levels and pulsatile release of LH, FSH, estradiol, and estrone and the rate of occurrence of HFs (measured objectively) were evaluated in patients with a defect of GnRH secretion [isolated gonadotropin deficiency (IGD)], patients with abnormalities of afferent input to GnRH neurons [hypothalamic amenorrhea (HA)], and postmenopausal women with severe HFs. Patients with IGD had received estrogens, which were discontinued before study. Patients with HA had experienced regular menses before disease onset, which followed emotional stress or weight loss. Studies were limited to HA patients with estrogen levels in the postmenopausal range. Pulsatile LH release was absent in patients with IGD and was absent or greatly reduced in women with HA. Objectively measured and subjectively experienced HFs occurred in IGD but not in HA patients. These results suggest that HFs are not an obligatory consequence of low endogenous estrogen levels and that the absence of episodic LH and GnRH release (IGD) does not influence the occurrence of HFs. It is possible that the dysfunction of afferent input to GnRH neurons in HA somehow prevents HFs in these women with low endogenous estrogen secretion.

Adult↗

Differential permeability of uterine and liver vascular beds to estrogens and estrogen conjugates.

The role of capillary membrane permeability and the effect of plasma protein binding on the influx of unconjugated and conjugated estrogens into a target organ, the uterus, and a metabolic organ, the liver, were studied in anesthetized rats. In the absence of plasma proteins, estrone (E1) and estradiol (E2) were freely diffusible through the uterine capillaries, but influx was significantly reduced for estriol (E3) and estetrol. In the uterus, the influx of the conjugated estrogens was markedly restricted and approximated the influx of dextran, a vascular space marker. The polarity of the compound (based on the number of hydrogen bond-forming functional groups and the presence of charged groups) appeared to predict uterine endothelial membrane permeability better than the octanol/Ringer's partition coefficient. In contrast to the selective permeability properties of the uterine endothelial barrier, the limiting membrane lining the hepatic microcirculation, the hepatocyte cell membrane, was highly permeable to all unconjugated and conjugated estrogens. The addition of 4% albumin to the injection solution led to a significant inhibition of uterine influx of E2, but not E1 or E3. In the liver, only the influx of E1 sulfate was slightly diminished by 4% albumin. In all cases, the influx of estrogens greatly exceeded the rate that would be expected if only the fraction that was free (dialyzable) in vitro was diffusible in vivo. Human sera containing sex hormone-binding globulin and albumin caused inhibition of influx of E1 and E2 through the uterine capillary barriers, whereas in the liver, the influx of E2 sulfate, and E3 glucuronide were diminished. The results are compatible with a difference in permeability of the microvasculature of the two organs and a differential availability of protein-bound estrogen for influx into liver and uterus. With the exception of E1, which is nearly completely diffusible into both organs, the influx of estrogens and estrogen conjugates into liver is greatly amplified compared to that into a peripheral organ such as the uterus.

Animals↗

Alterations in ovarian steroid and gonadotrophin secretion preceding the cessation of regular oestrous cycles in ageing female rats.

To determine whether discernible alterations in neuroendocrine and/or ovarian function precede the loss of regular oestrous cycles in ageing female rats, the present study examined the pattern of gonadotrophin secretion near the time of ovulation and the pattern of ovarian steroid secretion in the early morning of pro-oestrus in middle-aged (10-12 months old) females displaying regular oestrous cycles and compared these with young (4 months old) animals. In addition, the subsequent reproductive patterns in these animals were observed and correlations between the changes in hormonal profiles and the decline in regular reproductive cyclicity were established. In middle-aged females which subsequently ceased to display regular oestrous cycles (middle-aged non-regular; M-NR) within 1-2 months, the pro-oestrous surge of LH was significantly reduced in magnitude. There was no difference in the LH surge between young females and middle-aged animals which maintained regular oestrous cycles (middle-aged regular; M-R) for at least 2 months. There also was no difference in the magnitude of the pro-oestrous FSH surge or in the secondary rise in FSH in the early morning of oestrus among young, M-R and M-NR females. In a separate group of middle-aged females which subsequently became M-NR, serum concentrations of both oestradiol and testosterone in the early morning of pro-oestrus were markedly raised over those in the young and M-R groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗

Effects of the (imBzl)D-His6, Des-Gly analog of GnRH on gonadotropin and estradiol secretion in normal women.

The acute gonadotropin and estradiol responses following single subcutaneous injections of 10, 50, 100 and 200 micrograms of [(imBzl)]D-His6,Pro9-NEt]-GnRH were compared to those after 100 micrograms of [D-Trp6, Pro9-NEt]-GnRH. The gonadotropin responses after 50-100 micrograms of the D-His analog of GnRH were equivalent to those following 100 micrograms of the D-Trp analog. The ovarian E2 response, a reflection of the total cumulative secretion of gonadotropins, was similar at 100 micrograms of each analog. The estradiol response paralleled the increasing gonadotropin response accompanying the graded doses of the D-His analog, indicating the lack of a direct inhibitory action of this GnRH agonist on the ovary. Assessment of both gonadotropin and estradiol responses appears to be satisfactory for assessing relative potency among GnRH agonistic analogs.

Adolescent↗

Pituitary hormones during the menopausal hot flash.

Eighteen postmenopausal women with severe hot flashes had continuous recordings of finger temperature and skin resistance as objective indexes of flushing episodes, and serial measurements of anterior pituitary hormones as indirect indexes of hypothalamic neurotransmitter activity. Significant increases of growth hormone, adrenocorticotropic hormone (ACTH), and luteinizing hormone (LH) occurred with maximal concentrations at 30, five, and 15 minutes, respectively, after the onset of the skin temperature rises. No significant fluctuations of prolactin (PRL), thyroid-stimulating hormone (TSH), or follicle-stimulating hormone (FSH) were observed. The mean serum cortisol concentration increased 15 minutes after the hot flash, presumably consequent to the preceding elevation of ACTH. Pituitary ACTH release may be secondary to hypothalamic cooling, whereas increased growth hormone and LH output and the thermoregulatory adjustments comprising the flushing episodes are all consistent with cyclic episodes of increased hypothalamic norepinephrine activity.

Adrenocorticotropic Hormone↗

Origin of serum progestins in polycystic ovarian disease.

The glandular origin of excess circulating steroid hormones in women with polycystic ovarian disease has been difficult to establish with previously described perturbation techniques. Recently it was demonstrated that daily administration of a potent gonadotropin-releasing hormone agonist achieves complete and reversible suppression of ovarian steroid secretion. To examine the source of C-21 steroid hormones, circulating levels were measured before and after administration of the same agonist in polycystic ovarian disease subjects and normal control subjects. Serum levels of these hormones were also determined after administration of dexamethasone and adrenocorticotropic hormone (ACTH) as well as bilateral oophorectomy. Subjects with polycystic ovarian disease exhibited significant elevations of serum pregnenolone, 17OH -pregnenolone, and 17OH -progesterone by comparison with normal control subjects. The glandular origins of the excess levels of pregnenolone and 17OH -pregnenolone were more difficult to determine and appear to be different from that of 17OH -progesterone.

17-alpha-Hydroxypregnenolone↗

Estrogen replacement therapy by transdermal estradiol administration.

To determine whether the nonoral administration of estradiol (E2) might provide physiologic replacement without alteration of hepatic function, 20 postmenopausal women were studied before and after 3 weeks of treatment with either E2-containing transdermal therapeutic systems or placebo. Twenty premenopausal women were also studied. With E2-containing systems, serum E2 and estrone levels were restored to the premenopausal range. Variable responses of the different biochemical and biologic markers of the actions of E2 were observed. The most sensitive marker was vaginal cytology, with the E2 dosage reverting the maturation index to premenopausal values. Hot flashes, measured objectively, were reduced in frequency but not abolished. Serum levels of follicle-stimulating hormone and luteinizing hormone were lowered but remained higher than the premenopausal range. No significant changes were noted in urinary calcium/creatinine and hydroxyproline/creatinine ratios, which were used as markers of bone resorption. With active systems, no significant changes were noted in the concentrations of the hepatic proteins renin substrate and thyroxine-binding globulin or in the binding capacities of cortisol-binding globulin and sex hormone-binding globulin. These results indicate that transdermal E2 administration may be used to provide estrogen replacement while exerting limited effects on hepatic function.

Calcium↗

Physical characteristics and sex hormone levels in patients with osteoporotic hip fractures or endometrial cancer.

Comparisons were made of the physical characteristics and the sex hormone levels of 50 postmenopausal women, half of whom had sustained an osteoporotic hip fracture while the remainder had developed endometrial carcinoma. None of the patients had received estrogen replacement therapy for longer than 3 months during their lifetime. At the time of injury hip fracture patients were found to be lighter (121 +/- 5 versus 167 +/- 9 pounds) and older (73.4 +/- 1.0 versus 62.6 +/- 1.7 years) than the cancer patients at the time of diagnosis. Estrone, estradiol, percentage of free estradiol, and free estradiol levels were significantly lower in the hip fracture patients than in subjects with endometrial cancer, while sex hormone-binding globulin levels were significantly higher in the former group. Androstenedione and testosterone levels were similar. Previous studies have shown that the incidence of both lesions is influenced by body size. These data suggest that body size may exert this influence through alteration of endogenous estrogen metabolism with hip fracture patients having lower concentrations and endometrial cancer patients having higher concentrations of endogenous estrogens.

Aged↗

An increase in high-molecular weight renin substrate associated with estrogenic hypertension.

We have previously reported that estrogens have the potential to induce new forms of renin substrate in addition to elevating the major circulating form of this protein. One of these estrogen-induced forms had a molecular weight in excess of 150,000. In this study we have compared the plasma concentration of the high-molecular-weight renin substrate in normotensive women receiving estrogen therapy and women with estrogenic hypertension. A statistically significant elevation of this protein was associated with estrogenic hypertension and normotensive pregnant women at term. This form of renin substrate differed from the major form with respect to electrophoretic mobility, isoelectric point, and immunologic cross-reactivity. In addition, kinetic analysis indicated that this high-molecular-weight substrate has a significantly higher affinity for the enzyme renin than the major circulating form (Km = 1800 +/- 290 versus 3520 +/- 260 ng angiotensin I equivalents/ml). These results suggest that in addition to renin substrate concentration, substrate composition may play an important role in blood pressure regulation.

Adult↗

Gonadotropin secretion during prolonged hyperprolactinemia: basal secretion and the stimulatory feedback effect of estrogen.

Inoculation of cyclic female rats with the prolactin (Prl)/growth hormone-secreting pituitary tumor, MtT.W15, resulted in a cessation of estrous cyclicity within 5--10 days. Associated with this acyclicity was a persistently low serum concentration of estradiol and marked increases in both circulating Prl and progesterone. At Day 26 of acyclicity, basal serum luteinizing hormone (LH) values measured in samples taken every 20 min from 0900--1100 h were significantly reduced when compared to cyclic, nontumor animals on diestrus Day 2. There was no difference in basal follicle-stimulating hormone (FSH) concentrations. In a separate group of acyclic, tumor-bearing females 42--56 days after transplantation, a single s.c. injection of 20 micrograms estradiol benzoate (EB) at 1030 h elicited significant increases in both serum LH and FSH values between 1700 and 1830 h on the next day. The magnitude of the LH surge was reduced and that of FSH was increased in tumor-bearing animals when compared to cyclic, nontumor females given a similar EB injection on diestrus Day 1. These results demonstrate that chronic hyperprolactinemia is associated with inhibition of basal LH secretion and ovarian estrogen production and an increase in circulating progesterone concentrations. Nevertheless, the stimulatory feedback effects of estrogen on LH and FSH release are still present and functioning in acyclic female rats under chronically hyperprolactinemic conditions. These data suggest that the cessation of regular ovulatory cycles associated with hyperprolactinemia may be due to a deficiency of LH and/or estrogen secretion, but not to a lack of central nervous system response to the stimulatory feedback action of estrogen.

Animals↗

Impermeability of the rat blood-brain barrier to exogenously administered gonadotropin-releasing hormone.

To assess the permeability of the blood-brain barrier (BBB) to exogenously administered gondatrophin-releasing hormone (GnRH), a study was performed in male-rats using the double isotope, intracarotid, single injection technique of Oldendorf. The mean (+/- SEM) brain uptake indices (BUI) of 3H-GnRH in comparison to a freely diffusible reference compound, 14C-butanol, were 1.1 +/- 0.2, 3.5 +/- 0.7 and 3.0 +/- 0.6 when the injection vehicles were Ringer's lactate, rat serum and human serum, respectively. The BUI of 3H-GnRH was similar to that of 3H-inulin, a nondiffusible compound. With different concentrations, the BUI of 3H-GnRH did not change significantly. These data indicate that the BBB of the male rat is impermeable to exogenously administered GnRH.

Animals↗

Induction of hot flashes in premenopausal women treated with a long-acting GnRH agonist.

To examine the relationship between the occurrence of menopausal hot flashes and the pulsatile release of LH, we have investigated the serum hormone levels and the occurrence of hot flashes by objective recordings in five women with endometriosis given daily injections of a long-acting GnRH agonist (GnRH-a) for 28 days. Results were compared to the findings made in 25 young women 6-8 weeks after bilateral oophorectomy. Serum levels of estrone and estradiol were similar in the subjects given GnRH-a and the women who underwent a surgical castration. In comparison with values before GnRH-a administration, the mean FSH level was lower whereas the mean LH concentration was significantly higher (P less than 0.01) on the last day of therapy. The coefficients of variations of both gonadotropins measured during 4-h sampling periods at 20-min intervals before and at the end of GnRH-a administration were significantly reduced (P less than 0.01) with therapy. During the total of 20 h of frequent sampling in the 5 subjects, 15 pulses (20% rise from nadir) of LH and 12 pulses of FSH were detected before GnRH-a, whereas only 2 and 8 pulses, respectively, were observed on day 28 of treatment. Hot flashes were observed in both groups of patients. The proportion of women experiencing hot flashes, the rate of occurrence/h and the characteristics of the physiological changes were similar in the 2 groups of women. These data indicate that hot flashes can occur in the absence of prominent LH pulses, suggesting the pulsatile release of this hormone is merely associated with the hot flash rather than being etiological.

Castration↗