Title: Alpha‐2 adrenoreceptors mediate clonidine‐induced hypoinsulinaemia in sheep
Abstract: Insulin and glucose concentrations in the blood of sheep were measured before, and up to 7 h after, feeding. The patterns reported by other workers were confirmed, namely: an early insulin concentration peak and decline in glucose concentration and, later, more prolonged changes. Intravenous injection of clonidine (2 μg/kg or 5 μg/kg) just before offering food caused hypoinsulinaemia and hyperglycaemia, abolishing the normal patterns. Administration of idazoxan (0.1 mg kg‐ 1 ), an alpha‐2 adrenoreceptor antagonist, before a 2 μg/kg dose of clonidine, completely blocked the effects of clonidine. By contrast, with prior injection of prazosin (0.1 mg/kg), an alpha‐1 adrenoreceptor antagonist, the hypoinsulinaemia in response to clonidine still occurred and the hyperglycaemia appeared to be enhanced. The antagonists injected alone had only slight effects: idazoxan caused a slight hypoglycaemia and prazosin a slight hyperglycaemia. The results indicate that clonidine causes hypoinsulinaemia and hyperglycaemia by action on alpha‐2 receptors. Possible mechanisms are discussed.
Publication Year: 1991
Publication Date: 1991-09-01
Language: en
Type: article
Indexed In: ['crossref', 'pubmed']
Access and Citation
Cited By Count: 7
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot