Journal of the Korean Geriatrics Society  2003;7(2):95-100

Effects of Ca2+ Channel Blockers on Expression of L-type Voltage Dependent Ca2+ Channels in Vascular Smooth Muscle Cells Obtained from the Aorta of Diabetic Rats.

Hyung Joon YOO

Keywords

Diabetes; Vascular smooth muscle cell; Calcium channel

Country

Republic of Korea

Language

Korean

Abstract

BACKGROUND: The proliferation of vascular smooth muscle cells(VSMCs) is an important process in the pathogenesis of atherosclerosis. VSMCs proliferation is closedly related to the cytosolic calcium flux via L-type voltage dependent calcium channel. OBJECTIVES: To investigate the role of cytosolic Ca2+ in the proliferation of VSMCs. METHODS: The proliferation of aortic vascular smooth muscle cells of streptozotocin induced diabetic rats, acquired by enzymatic method. Cell counting, and calcium agonists(Bay K 8644 10(-6)M) or calcium antagonists(verapamil 10(-6)M). Cytosolic calcium ion was measured with Fura 2 method. Calcium channel gene expression was detected with RT-PCR method. RESULTS: VSMCs of diabetic rats were more proliferated than those of nondiabetic ones. Bay K 8644 enhanced VSMCs proliferation of both groups. Verapamil blocked the incremental effects induced by Bay K 8644. Expression of calcium channel gene was enhanced by Bay K 8644 and was reversed by vera- pamil. CONCLUSION: The enhanced proliferation of VSMCs is associated with the increment in cytosolic calcium, which is accompli shed through the expression of L-type voltage dependent calcium channel.