Cortisol, growth hormone and prolactin responses to insulin-induced hypoglycaemia in hyperthyroid patients before and during beta-adrenoceptor blockade.
Two beta-adrenoceptor blocking agents, metoprolol (beta-1-selective) and propranolol (non-selective), were used in the treatment of hyperthyroid patients. The response of pituitary stress hormones to insulin-induced hypoglycaemia was investigated before and during beta-adrenoceptor blockage. Treatment with metoprolol (n=10) or propranolol (n=10) produced no changes in the cortisol or prolactin responses to hypoglycaemia. Moreover the growth hormone response remained unaltered during treatment with metoprolol. A small, but statistically significant, augmentation of growth hormone response was obtained during treatment with propranolol. When twelve subjects, euthyroid after final conventional treatment (surger), radioiodine or thyrostatic drugs), were re-examined, the cortisol and prolactin responses were unchanged, although growth hormone concentrations reached a slightly higher maximum value (P less than 0.01). It was concluded that treatment with beta-blocking agents in hyperthyroid subjects has no clinically important influence on the release of pituitary stress hormones during hypoglycaemia.
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D005260:Female; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D006980:Hyperthyroidism / Q000188:drug therapy; D007003:Hypoglycemia / Q000139:chemically induced; D007328:Insulin / Q000494:pharmacology; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use; D008875:Middle Aged; D011388:Prolactin / Q000378:metabolism*; D011433:Propranolol / Q000627:therapeutic use; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D000319:Adrenergic beta-Antagonists; D007328:Insulin; D014284:Triiodothyronine; D011388:Prolactin; D013006:Growth Hormone; D011433:Propranolol; D008790:Metoprolol; D013974:Thyroxine; D006854:Hydrocortisone