title: Protection against alloxan-induced diabetes in mice by stimulation of alpha 2-adrenergic receptors.
abstract: A single intravenous injection of alloxan in mice induced hyperglycemia in a dose dependent fashion. This diabetogenic action of alloxan was prevented by a single intraperitoneal injection of the alpha 2-adrenergic agonists, i.e. oxymetazoline, clonidine or epinephrine 40 min prior to the injection of alloxan. The alpha 1-adrenergic agonists, i.e. methoxamine and phenylephrine, and a beta-adrenergic agonist, isoproterenol, failed to prevent the diabetogenic action of alloxan. The inhibitory effect of clonidine on alloxan-induced diabetes was antagonized by yohimbine or phentolamine, but not by prazosin. Although alpha 2-adrenergic agonists caused a transient hyperglycemia at the time of alloxan administration (40 min after the administration of alpha 2-adrenergic agonists), the plasma glucose level at the time of alloxan injection did not correlate with the anti-diabetogenic effect of alpha 2-adrenergic agents. These results clearly demonstrate that the alpha 2-adrenergic mechanism which inhibits insulin release from pancreatic B cells prevented the diabetogenic action of alloxan in mice.
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000496:Alloxan / Q000037:antagonists & inhibitors; D000818:Animals; D003000:Clonidine / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000517:prevention & control*; D004837:Epinephrine / Q000494:pharmacology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010109:Oxymetazoline / Q000494:pharmacology; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D013268:Stimulation, Chemical
chemical_list: D000316:Adrenergic alpha-Agonists; D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D000496:Alloxan; D010109:Oxymetazoline; D003000:Clonidine; D004837:Epinephrine