Fetal sera (9-20 weeks fetal age, n = 80) and pituitary glands (9.5-20 weeks, n = 36) obtained from hysterotomy specimens, and amniotic fluids (amniocentesis; 8-40 weeks, n = 123) were assayed for FSH, LH (betaLH assay) and CG (betaCG assay). Results are expressed as mass of pure hormone. Prior to 12 weeks fetal age, pituitary, serum and amniotic fluid concentrations of LH and FSH were low or unmeasurable. In contrast, levels of CG in serum and in amniotic fluid were clearly measurable prior to 12 weeks. There was a definite CG peak at 11-14 weeks with levels up to 550 ng/ml in serum and 7400 ng/ml in amniotic fluid. Although LH levels began to rise at 12 weeks, when CG levels started to decline, serum levels of LH from 14-20 weeks in males (2-13 ng/ml) were still lower than the majority of CG levels at this time (6-115 ng/ml). These observations suggest that CG is the primary stimulus to the fetal Leydig cell which results in testosterone secretion (peak 11-17 weeks) and masculine differentiation of the genital tract. Significantly lower concentrations of both FSH and LH were observed in pituitary, serum and amniotic fluid between 12-20 weeks fetal age in males compared to females. This may be a result of feedback inhibition by the higher concentrations of testosterone in males at this time. Amniotic fluid FSH and LH concentrations correlated with their respective serum and pituitary values (P less than 0.01) indicating that amniotic fluid may provide a convenient index of fetal serum concentrations.

Allgrove syndrome (isolated glucocorticoid deficiency, achalasia and alacrima) was found in eight members of an inbred French Canadian/North American Indian pedigree. The high degree of consanguinity supports an autosomal recessive mode of inheritance for this disorder. Six patients presented with hypoglycaemia and other evidence of cortisol deficiency between 2.5 and 8 years of age; however, two others became cortisol deficient after initial testing showed normal cortisol responses to ACTH, evidence that the glucocorticoid insufficiency of this syndrome may not be congenital, but may develop as late as the third decade. No evidence of mineralocorticoid deficiency has been found during 65 patient-years of follow-up. Alacrima was the earliest and most consistent clinical sign of Allgrove syndrome. Other manifestations of peripheral or autonomic neuropathy were found in four patients. The patients showed similar facial features, and three had significant velo-pharyngeal incompetence. All showed oesophageal dysmotility even in the absence of symptomatic dysphagia. In-vitro studies of lymphocyte ACTH binding showed no differences from normal controls. If such lymphocyte binding, as has been suggested, reflects adrenal ACTH receptor activity, these data would suggest that the glucocorticoid deficiency of Allgrove syndrome is not the result of a defect in that receptor. However, the observation that ACTH does not elicit increased adenylate cyclase activity even in normal lymphocytes casts considerable doubt on the physiological significance of ACTH binding to lymphocytes. It seems likely, therefore, that true ACTH receptors are not expressed on peripheral lymphocytes, and any conclusions regarding a possible receptor defect in Allgrove syndrome must await studies of receptor expression on adrenal cell membranes.

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