Role of nitric oxide in insulin-induced hypothermia in rats

• Published in: Brain research bulletin Vol. 54; no. 1; pp. 49 - 53
• Main Authors: Almeida, Maria Camila, Branco, Luiz Guilherme S
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 2001; Elsevier Science
• Subjects: Animals; Biological and medical sciences; Blood Glucose; Body temperature; Body Temperature - drug effects; Enzyme Inhibitors - pharmacology; Fundamental and applied biological sciences. Psychology; Hypoglycemic Agents - pharmacology; Hypothermia; Hypothermia - chemically induced; Hypothermia - metabolism; Injections, Intraventricular; Insulin; Insulin - pharmacology; Male; NG-Nitroarginine Methyl Ester - pharmacology; Nitric oxide; Nitric Oxide - metabolism; Nitric oxide synthase; Nitric Oxide Synthase - antagonists & inhibitors; Nitric Oxide Synthase - metabolism; Rats; Rats, Wistar; Thermoregulation. Hibernation. Estivation. Ecophysiology and environmental effects; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Nitric oxide synthase; Insulin; Nitric oxide; Body temperature; Hypothermia; Pancreatic hormone; Rat; Enzyme; Rodentia; Central nervous system; Nitric-oxide synthase; Vertebrata; Mammalia; Oxidoreductases
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/S0361-9230(00)00423-8

Hypothermia is a well-known phenomenon which accompanies hypoglycemia in mammals. The present study was designed to test the hypothesis that nitric oxide (NO) plays a role in insulin-induced hypothermia. The body temperature (Tb) of awake, unrestrained rats was measured before and after systemic infusion of insulin (2U.kg
−1.h
−1), and intracerebroventricular administration of N
G-nitro-
L-arginine methyl ester (L-NAME, a nonselective NO synthase inhibitor, 200 μg/1 μl). We observed a significant reduction in body temperature after insulin infusion. L-NAME alone caused no significant change in body temperature. When the two treatments were combined, no change in Tb was observed. The data indicate that NO plays a key role in insulin-induced hypothermia.