Robert M. Boyar

Cortisol Secretion and Metabolism in Anorexia Nervosa

We studied cortisol secretion and metabolism in 10 women with anorexia nervosa. The 24-hour mean plasma cortisol concentration was 8.9 mug per deciliter (controls, 4.9) (P less than 0.01). Secretory patterns showed normal circadian rhythms. Cortisol half-life was prolonged from 60 to 78 minutes (P less than 0.01), and metabolic clearance rate was decreased from 359 to 177 liters per day (P less than 0.001). Cortisol production was normal (19.4 mg per day). Urinary cortisol was slightly elevated in two of five patients. These findings, as well as the increased tetrahydrocortisol/tetrahydrocortisone ratio (1.2 vs 0.65, P less than 0.01), also appear in hypothyroid patients. Thyroid-function studies showed normal total and free thyroxine and thyrotropin, but low plasma tri-iodothyronine levels (52.7+/-13.2 vs. 137.8+/-24.1 ng per deciliter in the controls, P less than 0.001). In five additional patients with anorexia nervosa studied before and after short-term tri-iodothyronine administration, metabolic abnormalities decreased as plasma tri-iodothyronine levels rose to or above normal.

weight and Circadian Luteinizing Hormone Secretory Pattern in Anorexia Nervosa

&NA; In previous studies we had established that emaciated women with active primary anorexia nervosa (AN) had immature 24‐hr luteinizing hormone (LH) secretory patterns. In this study, we have examined the circadian LH patterns of eight women with AN who had partially or fully recovered their ideal weights. Three of the women were studied before and after weight gain and five women were studied only after the appearance of binge‐eating and consequent weight gain (by history). Our findings are: (1) The adult (mature) circadian LH secretory pattern was not present in women who had partially or totally achieved ideal weight but who otherwise remained symptomatic; (2) those women who showed both weight gain and normalization of LH pattern were also symptomatically improved in other respects; (3) the degree of immaturity of pattern did not correlate reliably with the duration of illness, the degree of fatness, or the extent of deficit from ideal weight; (4) the mode of illness onset and the type of secretory pattern were not related; and (5) the return of menses did not show a simple relationship to weight, fatness, or maturity of LH pattern.

Daily Rhythms in Cortisol and Melatonin in Primate Cerebrospinal Fluid

Cerebrospinal fluid was continuously collected from the cisternal-cervical subarachnoid space of chair-restrained rhesus monkeys. The concentrations of melatonin and cortisol were measured in the cerebrospinal fluid. Under diurnal lighting (light:dark, 12:12 h) melatonin concentrations were elevated during darkness and low during illumination. The melatonin rhythm persisted in constant darkness but was suppressed in constant illumination. Under diurnal lighting, cortisol concentrations were elevated in the early portion of the light period. This daily rhythmicicty of cortisol secretion was not altered by constant illumination or constant darkness. The differential response of the two hormones to constant light suggest that the daily fluctuation of melatonin secretion was not responsible for the daily rhythmicity of cortisol secretion in the rhesus monkey.

LHRH responsiveness in anorexia nervosa: intactness despite prepubertal circadian LH pattern.

&NA; Consistent with previous findings, six women with primary anorexia nervosa who underwent 24‐hour endocrine studies were all observed to have immature (prepubertal or pubertal) patterns of circadian luteinizing hormone (LH) secretion. This abnormality was present despite negligible weight deficit (but active symptomatology) in three of the women. Regardless of the extent of immaturity of circadian pattern, each woman showed a completely normal release of LH in response to the single intravenous administration of luteinizing hormone releasing hormone (LHRH). These findings provide further evidence for the intactness of pituitary function and for the possibility of a functional hypothalamic disturbance in anorexia nervosa. The discrepant finding in certain other studies of inadequate LH response to LHRH in women with anorexia nervosa is reviewed, and the potential influences of differing variables in these studies and the possibility of a heterogeneous illness are emphasized.

Pituitary microadenoma and hyperprolactinemia: a cause of unexplained secondary amenorrhea.

The recent development of precise and sensitive radioimmunoassay methods for the measurement of human prolactin has resulted in a large body of data concerning the regulation of this hormone in phy...

The effect of oral contraceptive treatment on the serum concentration of dehydroisoandrosterone sulfate

Dehydroisoandrosterone sulfate (DS), the major C19-steroid in the human circulation, was measured in serum obtained from blood samples collected daily (8 to 10 A.M.) throughout the menstrual cycles of eight normal, presumably ovulatory women and daily throughout the treatment cycles in four women taking an oral contraceptive (norethindrone, 1 mg., plus mestranol, 80 mcg.). The serum concentrations of DS in the ovulatory women ranged from 1,025 to 4,200 ng. per milliliter; mean, 2,062 +/- 137 ng. per milliliter (mean and standard error; n = 213). Serum DS concentrations during the follicular and luteal phases of the menstrual cycles of these women were similar. In women taking the oral contraceptive, the plasma DS concentrations ranged from 475 to 1,400 ng. per milliliter (mean, 895 +/- 83; n = 119). The 24 hour secretory pattern of DS was evaluated in one subject during a nontreatment cycle and again after 20 days of oral contraceptive treatment. In this subject, the mean serum DS level was 34 per cent lower during oral contraceptive treatment than the level before treatment. The decrease in the serum concentration of DS during oral contraceptive treatment likely results from a reduction in adrenal DS secretion since DS secretion by the normal human ovary is negligible and ovarian dehydroisoandrosterone secretion is small. Therefore, it is likely that the reduced serum DS levels in women taking oral contraceptives are the consequence of reduced adrenal secretion of DS resulting from reduced release of adrenocorticotropic hormone.

Regulation of Gonadotropin Secretion in Turner's Syndrome

Abstract To determine the role of body fat in regulating secretion of luteinizing hormone and follicle-stimulating hormone, we measured both at 20-minute intervals for 24 hours in eight children with Turners syndrome. The 24-hour mean luteinizing hormone levels varied from 20.2 to 70.5 mlU per milliliter. Total body weight, total body fat and percentage of body fat showed a significant negative correlation with the 24-hour mean luteinizing hormone concentrations (P<0.01). The 24-hour mean follicle-stimulating hormone concentrations ranged from 60.4 to 229 mlU per milliliter, with a significant negative correlation between total body fat and percentage body fat and the 24-hour mean concentrations (P<0.05). These negative correlations were not mediated by estrogens or androgens. (N Engl J Med 298:1328–1331, 1978)

The 24-Hour Secretory Pattern of LH and the Response to LHRH in Transsexual Men

Ten separate aspects of hypothalamic and pituitary function were studied in 13 male-to-female transsexuals and compared to the results of 7 heterosexual adult men. In 4 of 5 transsexuals, the 24-hour mean serum concentration of LH, the LH pulse frequency or amplitude, or the apparent half-life of disappearance of serum LH were greater than the 95% confidence limit of normal men. The maximum concentration of LH or FSH following the administration of 100 µg LHRH, the area under the response curve of LH or FSH following LHRH, or both were significantly greater than normal in 5 of 13 male-to-female transsexuals. The response of LH following the administration of LHRH was repeated in 3 subjects during estrogen therapy, and in one there was a paradoxical increase in the response of LH. Transsexualism may be associated with a neuroendocrine defect in the hypothalamus or pituitary that is characterized by high-frequency, high-amplitude pulsatile secretion of pituitary LH.

Analysis of secretory patterns of prolactin and gonadotropins during twenty-four hours in a lactating woman before and after resumption of menses

Twenty-four hour secretory patterns of prolactin, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were obtained on two separate occasions from a woman with late physiologic lactation. The studies were performed 26 and 34 months after her childs birth. During the initial study, she had amenorrhea, and her child suckled 13 per cent of the 24 hour period (Study 1). At the time of the second study, she had resumed regular menses and her child suckled for 7 per cent of the 24 hour period (Study 2). The average concentrations of prolactin during Studies 1 and 2 were 40 +/- 1.0 (mean and standard error; No. = 72) and 31 +/- 1.4 ng. per milliliter, respectively. The mean plasma prolactin concentration in Study 1 was significantly greater than that in Study 2 (p less than 0.001). The plasma concentrations of LH and FSH were significantly less in Study 1 than in Study 2 (p less than 0.001 and less than 0.01, respectively). It is concluded that hyperprolactinemia and hypogonadotropinemia were endocrinologic correlates of the amenorrhea of late physiologic lactation in this woman.

Testicular function in transsexual men.

Although the sperm counts of 5 of 8 adult male-to-female transsexuals were low, other aspects of testicular function were normal. Plasma production rates of testosterone averaged 6.4 mg/24 hours, a value similar to the 5.7 mg/24 hours produced by heterosexual adult men. Production rates of 17β-estradiol and estrone, 55µg/24 hours and 52 µg/24 hours, were also normal. Observed abnormalities of pituitary function and pituitary response to LHRH cannot be explained by abnormal testicular steroidogenesis.