Effect of insulin on the decreased beta-adrenergic responses of duodenum and atrium isolated from streptozotocin diabetic rats.
1. Decreased beta-adrenergic responses have been reported in both gastro-intestinal tract and atrium of experimentally-induced diabetic rats. The present study was undertaken to investigate in vitro effects of insulin on decreased beta-adrenergic responses of the duodenum and atrium from streptozotocin-diabetic rats. 2. Insulin incubation (16.67 micrograms/ml) in bathing medium for 5 hr enhanced the decreased beta-adrenergic responses in the diabetic rat duodenum, but not those in the diabetic atrium. Incubation of bovine insulin with anti-bovine insulin antibody in the test-tube inhibited the improving effect of insulin on the decreased beta-adrenergic responses of diabetic rat duodenum. 3. In vitro treatment with the same dose of bovine insulin in bathing medium caused a decrease in the beta-adrenergic responses of the atria from both non-diabetic and diabetic rats. Anti-bovine insulin antibody also abolished the inhibitory effect of insulin on the rat atria. 4. These results strongly suggest that the experimental diabetes affects beta-adrenergic responsiveness of the rat gastro-intestinal tract through a different mechanism from that of the rat myocardium.
Oztürk
Y
Y
Anadolu University, Faculty of Pharmacy, Department of Pharmacology, Tepebaşi Eskişehir, Turkey.
Yildizoğlu-Ari
N
N
Altan
V M
VM
Ozçelikay
A T
AT
D000420:Albuterol / Q000494:pharmacology; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D004386:Duodenum / Q000187:drug effects*; D006321:Heart / Q000187:drug effects*; D006325:Heart Atria / Q000187:drug effects; D066298:In Vitro Techniques; D007328:Insulin / Q000276:immunology / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D007328:Insulin; D011943:Receptors, Adrenergic, beta; D014284:Triiodothyronine; D007545:Isoproterenol; D013974:Thyroxine; D000420:Albuterol