Enhancement of insulin hypoglycaemia by beta adrenoceptor antagonists.
Interaction of insulin with beta-adrenoceptor antagonists was studied in conscious rabbits. Propranolol and metoprolol did not modify the peak of insulin hypoglycaemia but delayed its recovery. Practolol, sotalol and 1-INPEA enhanced the peak effect and delayed the recovery of insulin-induced hypoglycaemia. H 35/25 and d-INPEA did not modify insulin hypoglycaemia. The beta-blockers did not produce significant hypoglycaemia per se. Since sotalol, 1-INPEA (specific beta-adrenoceptor antagonists devoid of local anaesthetic activity); practolol and metoprolol (selective cardiac beta-1 adrenoceptor antagonists) enhanced hypoglycaemic action of insulin and H 35/25 (a selective beta-2 adrenoceptor antagonist) failed to affect it, it seems that selective beta-adrenoceptor blockade (similar to cardiac beta-1 adrenoceptors) mediates enhancement of insulin hypoglycaemia. Caution should, therefore, be exercised in administering beta-adrenoceptor antagonists and insulin together. A reduction in the dose of insulin may be necessary.
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001786:Blood Glucose / Q000032:analysis*; D003864:Depression, Chemical; D004357:Drug Synergism; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D011817:Rabbits
D000319:Adrenergic beta-Antagonists; D001786:Blood Glucose; D007328:Insulin; D004837:Epinephrine