A Single Intracerebroventricular Injection of Dexamethasone Elevates Food Intake and Plasma Insulin and Depresses Metabolic Rates in Adrenalectomized Obese (ob/ob) Mice

• Published in: The Journal of nutrition Vol. 125; no. 3; pp. 540 - 545
• Main Authors: Chen, Hsiao-Ling, Romsos, Dale R.
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.03.1995; American Society for Nutritional Sciences; American Institute of Nutrition
• Subjects: Adrenalectomy; Animals; Basal Metabolism - drug effects; Biochemistry; Biological and medical sciences; Dexamethasone - administration & dosage; Dexamethasone - pharmacology; Eating - drug effects; food intake; genetically obese (ob/ob) mice; glucocorticoid injection; Injections, Intraventricular; Insulin - blood; Kinetics; Male; Medical sciences; Metabolic diseases; metabolic rate; Metabolism; Mice; Mice, Obese; Nutrition; Obesity; Other nutritional diseases (malnutrition, nutritional and vitamin deficiencies...); Oxygen Consumption - drug effects; Phenotype; plasma insulin; Rodents; genetically obese (ob/ob) mice; metabolic rate; glucocorticoid injection; plasma insulin; food intake; Corticosteroid; Hyperinsulinemia; Animal model; Obesity; Dexamethasone; Rodentia; Single dose; Hereditary; Metabolism; Glucocorticoid; Insulin; Long term; Adrenalectomy; Vertebrata; Mammalia; Mouse; Food intake; Intracerebral administration; Hormonal investigation
• ISSN: 0022-3166; 1541-6100
• DOI: 10.1093/jn/125.3.540

A single intracerebroventricular (ICV) injection of dexamethasone rapidly (within 30 min to 3 h) increases plasma insulin and suppresses oxygen consumption in adrenalectomized ob/ob mice with minimal effects in lean mice. Food intake of these adrenalectomized ob/ob mice was unaffected by ICV dexamethasone during these short-term studies. However, in a longer-term study with adrenalectomized gold thioglucose-lesioned obese mice, food intake increased fourfold 6–8 d after a single ICV injection of dexamethasone. We have now further examined the time course of dexamethasone actions in adrenalectomized ob/ob and lean mice in the 96-h post-injection period. A single ICV injection of dexamethasone increased food intake 32% and plasma insulin 81%, and depressed oxygen consumption 11%, in adrenalectomized ob/ob mice during the 24-h period after injection, without increasing food intake or plasma insulin in lean mice. Oxygen consumption was 14% lower in lean mice 24 and 48 h after dexamethasone injection relative to saline-injected lean mice. Food intake and oxygen consumption in ob/ob mice returned to levels in saline-injected controls at 48 and 72 h after injection, respectively. Oxygen consumption of lean mice also returned to control levels at 72 h post-injection. Plasma insulin concentrations were similar in dexamethasone- and saline-treated ob/ob and lean mice at 96 h post-injection (the only time point examined other than 24 h). A single ICV injection of dexamethasone exerts both rapid (within 30 min to 3 h) and sustained (days) metabolic actions in ob/ob mice.