Abstract

As one main alkaloid isolated from the seed or leaves of Chinese herb Sophora alopecuroides L. matrine has very strong therapeutic actions on stroke, heart infarction, hepatitis, pain, etc. In this study, we want to observe the preventive effects of matrine on systolic cardiac dysfunction induced by homocysteine. Wistar rat right atria were acutely isolated and the contraction of rat atria was determined by inductive force transducers. Confocal laser scanning microscopy was used to measure [Ca²⁺]_i in acutely isolated atrial myocytes. The results showed that matrine 10, 30, and 100 μM can effectively attenuated the decrease of the contractile force of rat atria in the presence of homocysteine 5 mM. Moreover, the effects of homocysteine 5 mM on +dT/dt and –dT/dt of rat atria also can be reversed by matrine 10, 30, and 100 μM. Further study uncovered that matrine restored the reduction of [Ca²⁺]_i caused by homocysteine 5 mM. These suggested that matrine can prevent homocysteine-induced atrial systolic dysfunction by regulating [Ca²⁺]_i.

Key words: Matrine, inotropic effects, [Ca²⁺]_i.