The Open Neuroendocrinology Journal

2010, 3 : 221-226
Published online 2010 November 13. DOI: 10.2174/1876528901003010221
Publisher ID: TONEUROEJ-3-221

Effects of Removal of GABAergic tone in Dorsomedial Hypothalamic Nucleus on Peripheral Metabolic Responses

Gisele Cristiane Van , Carlos Henrique Xavier , Cândido Celso Coimbra , Marco Antônio Peliky Fontes and Elizabeth Lage Borges
Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627 CEP 31270-010, Belo Horizonte, MG, Brazil

ABSTRACT

Dorsomedial hypothalamus (DMH) plays a key role in the organization of functional responses to stress. Microinjection of GABAA antagonist bicuculline methiodide (BMI) into DMH evokes cardiovascular and neuroendocrine changes typically seen in experimental emotional stress. The aim of the present study was to investigate the peripheral metabolism of glucose following microinjection of BMI, (10pmol / 100nl) or vehicle (NaCl 0.9% - 100nl) into DMH. Male wistar rats were anesthetized and a guide cannula was set into DMH. The jejunal loop was isolated and perfused with Tyrode solution. Blood samples were taken 15 and 40 minutes after the beginning of experimental period. When compared to vehicle, BMI into DMH increased plasma insulin (0.22±0.04 vs. 0.34±0.04 ng/ml; P<0.05), decreased glucose- 6-phosphate in the liver (0.012±0.003 vs. 0.004±0.002 µmol/g tissue; P<0.05) and increased this same metabolite in muscle (0.14±0.05 vs. 0.43±0.10 µmol/g tissue; P<0.05). We found that DMH activation caused changes in plasma insulin and intermediate metabolite of glycolitic pathways.

Keywords:

Digestion, parasympathetic, autonomic, intestine.