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George A. Bray and Olav Trygstad


Lipolysis was studied in subcutaneous fat from obese and lean individuals. Glycerol was released at similar rates using pieces of fat weighing 40 or 100 mg. Isolated fat cells offered no advantage over segments of fat for the study of lipolysis. The lipolytic effects of epinephrine and norepinephrine were potentiated by phentolamine (an α-adrenergic blocking drug) and blocked by propranolol (a β-adrenergic blocking drug). Isoproterenol-stimulated lipolysis was also blocked by propranolol but was not potentiated by phentolamine. Thyrotrophin and a lipid-mobilizing factor from human pituitaries were lipolytic in vitro. Human growth hormone with or without dexamethasone had no effect on lipolysis.

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Mary A. Bray, Ozgul Muneyyirci-Delale, George D. Kofinas, and Francisco I. Reyes


Six women with pseudocyesis were studied by 15-min blood sampling for 12 to 24 h to determine their gonadotropin and PRL secretory profiles aiming to clarify the endocrine alterations in this form of hypothalamic amenorrhea. Clinical and biochemical evidence of hyperandrogenism was found in 4 patients. Persistent hyperprolactinemia was present only in one patient. Significant circadian and ultradian periodicities were identified by time series analysis in the 12-24 h profiles of FSH, LH and PRL secretion. Pulse analysis by the Van Cauter (UL-TRA.JN) method revealed a 24-h mean LH interpulse interval of 91±21 min with a mean LH amplitude of 5.4±0.8 IU/l. There was a significantly lower pulse frequency at night than during the daytime. The mean 24-h PRL interpulse interval and pulse amplitude were 134±22 min and 9.2±1.8 IU/l, respectively. Both FSH and LH mean levels were higher during the daytime than at night, while the reverse was true for PRL values. Decreased LH pulse frequeny and amplitude emerged as the most distinctive findings. Antecedent hypothalamic-pituitary aberrations due to other endocrinopathies and the timing of the hormonal assessment (e.g. recovery phase) may explain, at least in part, the reported heterogeneity of neuroendocrinologic findings in pseudocyesis.