Effect and Mechanism of Liraglutide on Vasodilatation of Thoracic Aortic Ring in Experimental Rats / 中国循环杂志

ABSTRACT

Objective: To investigate the effect and mechanism of liraglutide on vasodilatation of thoracic aortic ring in experimental rats. Methods: The thoracic aortic rings were isolated from 32 male SD rats and divided into 2 groups: Without endothelium group and With intact endothelium group, n=16 in each group. The contractile force of vascular ring was detected and the effect of liraglutide (1×10-5 mol/L) on vasodilatation of norepinephrine (NE, 1×10-6 mol/L) pre-contracted ring was observed. The aortic ring in With intact endothelium group was further divided into 2 sub-groups:①the aortic ring was pre-treated by the inhibitor of nitric oxide synthase (NOS) (L-NAME at 10-4 mol/L),② the aortic ring was pre-treated by non-specific ATP-sensitive-potassium (KATP) channel (Glibenclamide at 10-5 mol/L), n=8 in each group. The impacts of liraglutide on those 2 sub-groups were studied. Results: Liraglutide had no effect on isolated aortic ring at basic condition. Liraglutide at (10-5 mol/L) had vasodilatation effect in both Without endothelium and With intact endothelium groups, the effect was stronger in With intact endothelium group and the maximum vasodilatation reached 17%, P reached 14%, P>0.05. Conclusion: Liraglutide had obvious effect of vasodilatation on NE pre-contracted thoracic aortic ring in experimental rats, the mechanism might be related to NOS, while KATP channel could not block the vasodilatation effect of liraglutide.