Relaxatory Effect of Gamma-Aminobutyric Acid (GABA) is Mediated by Same Pathway in Diabetic and Normal Rat Mesenteric Bed vessel


1 Department of Basic Sciences, Gonabad University of Medical Sciences, Gonabad, Iran

2 Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran

3 Department of Physiology, School of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran


Diabetes related dysfunction of resistance vessels is associated with vascular occlusive diseases. Vasorelaxant agents may have a role in control of diabetic cardiovascular complications. Gamma aminobutyric acid (GABA) has demonstrated to cause vasorelaxation. The present study was designed to determine i) the vasorelaxatory effect of GABA on diabetic vessels and ii) the role of endothelium in GABAinduced vasorelaxation.
Materials and Methods
After Diabetes induction,. Mesenteric arteries of animals were perfused. Vascular beds were constrictedwith phenylephrine. GABA (1 to 50 μM) was added into the medium and perfusion pressure was then recorded.
In all groups of animals, relaxant response to GABA in mesenteric bed appeared. Although diabetes induction did not change mesenteric bed response to GABA, denuded vessels showed a reduced response to GABA both in control and diabetic animals.
GABA can induce endothelium dependent vasorelaxation in mesenteric vessels in normal and diabetic rats.


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