Differential effects of enterostatin, galanin and opioids on high-fat diet consumption

• Published in: Brain research Vol. 702; no. 1; pp. 55 - 60
• Main Authors: Barton, Chris, Lin, L., York, D.A., Bray, G.A.
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 08-12-1995; Amsterdam Elsevier; New York, NY
• Subjects: Animals; Biological and medical sciences; Colipases - pharmacology; Dietary Fats; Dose-Response Relationship, Drug; Eating - drug effects; Enzyme Precursors; Fat intake; Feeding; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; Galanin; Galanin - pharmacology; Male; Naloxone; Naloxone - pharmacology; Narcotics - pharmacology; Protein Precursors - pharmacology; Rats; Rats, Sprague-Dawley; Time Factors; U50488; Vertebrates: anatomy and physiology, studies on body, several organs or systems; κ-Receptor Enterostatin; Fat intake; U50488; Naloxone; Galanin; κ-Receptor Enterostatin; Feeding; Vertebrata; Agonist; Mammalia; Rat; Enterostatin; Rodentia; Fat; Supplemented diet; Neuropeptide; Opiate receptor κ
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/0006-8993(95)00966-8

Enterostatin, the activation peptide of pancreatic procolipase, suppresses high-fat diet consumption both centrally and peripherally. κ-opioid agonists are also known to stimulate fat intake. These experiments were conducted to determine if an opioidergic central pathway might mediate the effects of enterostatin and galanin on fat intake. Male Sprague-Dawley rats were adapted to a high-fat diet (56% energy) and were implanted with cannulae aimed at the lateral cerebral ventricle (LV) or third cerebral ventricle (3V). Injection of enterostatin (1 nmol, LV) suppressed high-fat diet consumption in fasted (20 h) rats. This inhibition of high-fat intake by enterostatin was attenuated by central injection of the specific κ-agonist U50488 (2.15, 21.5 and 215 nmol, LV) in a dose-dependent manner in fasted rats while only the highest dose of U50488 (215 nmol, LV) independently produced stimulation of high-fat diet consumption in sated rats. Galanin (0.1 nmol, 3V) induced consumption of high-fat diet in sated rats similar to that seen with U50488 and this stimulation was attenuated by peripheral injection of naloxone (1.0 mg/kg i.p.). We present a model which integrates the present data, as well as previous findings, in explaining a potential common opioid pathway modulating fat consumption.