Effects of ligustrazine on the contraction of isolated rabbit corpus cavernosum strips

Abstract

To investigate the role of ligustrazine on relaxation of the isolated rabbit corpus cavernosum tissuein vitro, the effects of ligustrazine on the corpus cavernosum were observed by using experimental method of smooth muscle strips. Concentration-responses to phenylephine (PE) and KCl were recorded. The results showed that ligustrazine concentration-dependently depressed the contraction response of smooth muscle strips induced by PE. The maximum percentage relaxation of cavernosal strips by ligustrazine was 74.1%±6.2% (compared with control: 21.9%±5.6%P<0.01). Ligustrazine concentration-dependently reduced the amplitude of the contraction induced by cumulative doses of PE or KCl, shifted the cumulative concentration response curves of PE and KCl to the right and depressed their maximal responses. It was concluded that ligustrazine could significantly relax the cavernosal muscle contraction induced by PEin vitro. The results suggested that ligustrazine inhibited calcium ion influx.

Keywords

ligustrazine / corpus cavernosum / calcium channel / concentration

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