AIMTo study the effect of Dehydrocorydaline and Verapamil (Ver) on intracellular free calcium concentration of myocardial cell ([Ca2+]i) under hypoxic condition.

METHODSWe adopted guinea-pig heart Langendorff instillation. The myocardial cells were isolated by collagenase (Type I, sigma)and marked by fluorescence ratio imaging. The suspension of myocardial cells was assigned to six groups: DHC, Ver, and control were each two. Each three groups was exposed to hypoxia and normoxia before determination of [Ca2+]i.

RESULTS(1) In normoxia state, [Ca2+]i was 120.5-8.3 nml/L (n = 20).( 2) In hypoxia state, the increased [Ca2+]i of myocardial cells was proportional to the time (degree) of hypoxia. Correlation coefficient (r) was about 0.98. (3) Under the condition of normoxia DHC and Ver decreased [Ca2+]i. (4) DHC was obviously slow the increase of [Ca2+]i after hypoxia.

CONCLUSIONIn normoxia and hypoxia, DHC decreases the increased [Ca2+]i. It can prevent intracellular calcium overload. We believe DHC may improve self-protected performance of myocardial cells.