Repeated hypothalamic stimulation with neuropeptide Y increases daily carbohydrate and fat intake and body weight gain in female rats

• Published in: Physiology & behavior Vol. 46; no. 2; p. 173
• Main Authors: Stanley, B.G. (The Rockefeller University, New York, NY), Anderson, K.C, Grayson, M.H, Leibowitz, S.F
• Format: Journal Article
• Language: English
• Published: United States 01.08.1989
• Subjects: ANIMAL FEMELLE; ANIMALES HEMBRA; Animals; Behavior, Animal - drug effects; BRAIN; CARBOHIDRATOS; CARBOHYDRATES; CEREBRO; CORPS GRAS; DIET; DIETA; Dietary Carbohydrates - administration & dosage; Dietary Fats - administration & dosage; Dietary Proteins - administration & dosage; ENCEPHALE; ESTIMULO; FATS; Feeding Behavior - drug effects; Female; FEMALE ANIMALS; Food Preferences - drug effects; GAIN DE POIDS; GANANCIA DE PESO; GLUCIDE; GRASAS; Hypothalamus - physiology; Injections, Intraventricular; Neuropeptide Y - administration & dosage; Neuropeptide Y - pharmacology; OVERWEIGHT; PEPTIDE; PEPTIDES; PEPTIDOS; PESO; POIDS; RAT; RATA; RATS; Rats, Inbred Strains; REGIME ALIMENTAIRE; SOBREPESO; STIMULATION; SURPOIDS; WEIGHT; WEIGHT GAIN; Weight Gain - drug effects
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/0031-9384(89)90251-5

Neuropeptide Y (NPY), repeatedly injected in the hypothalamic paraventricular nucleus (PVN), produces dramatic obesity and overeating in female rats maintained on a single nutritionally complete diet. In the present study, we investigated whether these effects could also be obtained in animals with a choice of three pure macronutrients: protein, carbohydrate, and fat. Female rats with indwelling PVN cannulas were injected with NPY (235 pmol) or its saline vehicle every 8 hr for 6 days. A third group was left undisturbed. Consumption of each macronutrient and body weight were measured every 24 hr for 6 days preinjection, 6 days during injections, and 21 days after the injections were terminated. Relative to vehicle or preinjection rates of body weight gain (approximately 1.5 g/day), NPY dramatically enhanced weight gain to a rate of 9.3 g/day and more than doubled total daily food intake. This augmentation was accounted for by increases in carbohydrate intake (+26.4 kcal/day) and fat intake (+48.5 kcal/day), with no significant potentiation of protein consumption. When the NPY injections were terminated, body weight and macronutrient intake returned to control levels within 1 or 2 weeks. These findings are consistent with a role for NPY in hypothalamic mechanisms of macronutrient intake and body weight regulation and suggest that disturbances in brain NPY may contribute to the development of eating and weight disorders.