The Journal of clinical endocrinology and metabolism
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J. Clin. Endocrinol. Metab. · Sep 1979
Plasma levels of adrenocorticotropin and cortisol in women receiving oral contraceptive steroid treatment.
The secretion rate and plasma concentration of the adrenocortical steroid cortisol is modified in subjects treated with estrogenic and/or progestational steroids. The effects of contraceptive steroids on the secretion of ACTH are poorly documented, however, In the current investigation, we found that concentrations of ACTH and cortisol in plasma obtained at 0800--0900 h from a group of women with normal cyclic menses (n = 4) ranged from 78--120 pg/ml and 77--137 ng/ml, respectively. ⋯ In women treated with Norinyl 1 + 80 (1.0 mg norethindrone plus 0.08 mg mestranol), plasma concentrations of LH, FSH, 17 beta-estradiol, and progesterone were significantly lower (P less than 0.001) than plasma levels of these hormones in normal women during the ovarian cycle. The mean daily plasma concentrations of ACTH were significantly lower (P less than 0.001), whereas plasma cortisol levels were significantly higher (P less than 0.001) in women treated with oral contraceptive steroids compared to the levels of these hormones in the untreated ovulatory women.
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J. Clin. Endocrinol. Metab. · Sep 1977
Potentiation of insulin action: a probable mechanism for the anti-diabetic action of sulfonylurea drugs.
Insulin action was assessed by measuring insulin-mediated glucose disposal (KI) in 13 non-ketotic diabetic patients both before treatment and after normalization of plasma glucose by diet (5 patients) or sulfonylurea (glipizide) therapy (8 patients). While the KI of the diet-treated group was unchanged by therapy, that of the glipizide-treated group was significantly increased. The data show that chronic glipizide therapy is associated with a potentiation of insulin action, which may account for the major anti-diabetic effect of this drug.
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J. Clin. Endocrinol. Metab. · Apr 1977
Comparative StudyInsulin, proinsulin, glucagon and gastrin in pancreatic tumors and in plasma of patients with organic hyperinsulinism.
Insulin, proinsulin, glucagon and gastrin were determined in extracts of tumors of 27 patients with pancreatic islet cell neoplasia of pancreas, in one patient with nesidioblastosis, in extracts of uninvolved portions of the pancreas in 11 of the tumor patients and of 15 control pancreases. Mean insulin concentration in solitary adenomas and in adenomas of patients with adenomatosis was higher than in control pancreases; however, in all but 1 patient the insulin concentration in neoplastic islet tissue was lower than in islet tissue of control pancreas, assuming islet volume is 1% of pancreas. The percentage of proinsulin was elevated in 52% of tumors. ⋯ The mean concentration of glucagon in tumors was lower than in control pancreases. Elevated concentration of gastrin was found in some adenomas. The data indicate: 1) insulin-secreting islet cell tumors have decreased storage capacity for insulin, 2) elevated concentration of proinsulin in tumors may be due to decreased capacity to store insulin and in some to decreased conversion of proinsulin to insulin as well, 3) tolbutamide stimulates the exaggerated release of a relatively constant fraction of insulin stored in adenomas. 4) solitary adenomas may contain excess amounts of pancreatic hormones in addition to insulin, 5) elevated plasma glucagon in patients with organic hyperinsulinism may indicate malignancy, microadenomatosis or multiple endocrine adenoma syndrome, and 6) chronic hyperinsulinism and hypoglycemia due to adenoma do not suppress insulin and proinsulin content of uninvolved pancreas.
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J. Clin. Endocrinol. Metab. · Jan 1977
Transient bitemporal hemianopsia during pregnancy after treatment of galactorrhea-amenorrhea syndrome with bromocriptine.
A patient is described with a galactorrhea-amenorrhea syndrome and an enlargement of the sella turcica. Pregnancy occurred after induction of ovulation with bromocriptine (and 2.5 years after pituitary irradiation). ⋯ One month after delivery the visual field of the left eye was almost normalized, while that of the right eye showed a definite improvement. Prior radiotherapy need not prevent visual complications from enlargement of pituitary adenomas during pregnancy.
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J. Clin. Endocrinol. Metab. · Jul 1976
Aldosterone response to hypoglycemia: evidence of ACTH mediation.
Insulin-induced hypoglycemia caused an increase in plasma aldosterone as well as in renin activity and cortisol. After the suppression of the renin-angiotensin system by the prior administration of propranolol, insulin-induced hypoglycemia still caused a significant increase in plasma aldosterone similar to the increase in plasma cortisol, though plasma renin activity was suppressed. ⋯ The increase of plasma aldosterone in response to exogenous ACTH was not different with or without the prior administration of dexamethasone. We conclude that ACTH is largely responsible for the increased aldosterone secretion after insulin-induced hypoglycemia.