| چکیده انگلیسی مقاله |
Objective: To investigate the role of central histamine Hi and H2 receptors on food intake in freely feeding and food - deprived rabbits. Design: Experimental study. Animals: Forty - two male New Zealand white rabbits weighing between 2.5 - 3 Kg. Procedure: A 23- gauge, 18mm long stainless steel guide cannula was surgically implanted into the lateral ventricle of brain, Intracerebroventricular injections of normal saline (control), promethazine and ranitidine at the same doses of 50, 100 and 200 jig /rabbit in a volume of 25 ul were performed using a 25 jil Hamilton’s syringe. Cumulative food intake was measured in freely feeding and food - deprived rabbits at the 0.5, 1, 2, 3, 6 and 24h after injections. Statistical analysis: Paired t-test, Factorial ANOVA and Duncan’s test. Results: Food deprivation for i6hincreased0.5, 1,2,3 and 6h cumulative food intake. In freely feeding rabbits, promethazine (50 jig) had no effect on food intake, and at the dose of 100 pg increased 1 and 2h feeding after injection, but at the dose of 200 pg increased 2 and 3h post- injection food intake. In the 1 6h food- deprived rabbits promethazine (50,100 and 200 jig) had no effect. Ranitidine at the doses of 50,100 and 200 pg produced no significant changes on food intake in both freely feeding and food- deprived rabbits. Prometliazine did not exert any significant effects on the 6 and 24h post- injection food intake. Conclusion: Based on the results of the present study it is concluded that the blockade of central Hi but not H2 receptors induce a short- lasting e citatory effect on food intake. Thus, central Hi receptor may have an important role in the central control of feeding behavior. J.Fac. Vet. Med. Univ. Tehran. 60,3:277-282,2005 |