Method: 1.We investigated concentration-dependent change in isometric tension and [Ca2+]i level simultaneously of the smooth muscle. 2.Before the start of all investigations, changes in [Ca2+]i and tension induced by 40 mMKCl were recorded as the control values(100%) in each specimen. 3.Then, we measured the inhibition by mepivacaine(0.1%-0.3%) to the contraction of vascular smooth muscle by 40 mMKCl.
Result: Mepivacaine suppressed the contraction of vascular smooth muscle 40 mMKCl in concentration dependent manner and also the increase in [Ca2+]i simultaneously.
Conclusion: Although it is said that mepivacaine has a vasoconstrictor action generally, in this study, low concentration of mepivacaine showed the direct relaxation action to vascular smooth muscle. As the opportunity of the dental treatment on the patient with a systemic disease has increased, it is expected that the frequency in use of mepivacaine increase in dental clinic. Therefore it is important to understand about the direct action to a vascular smooth muscle and its mechanism.