J Korean Geriatr Soc.  2000 May;4(1):28-34.

Role of Cytosolic Ca2+ in the Enhancement and Inhibition of the Proliferation of Vascular Smooth Muscle Cells

• Yoo HJ
• Ihm SH

Abstract

Background
: Vascular smooth muscle cells(VSMCs) proliferation is an important process in the pathogenesis and progression of atherosclerosis, Calcium is considered an important regulator of cellular proliferation. The major mechanism regulating VSMC cytoplasmic Ca2+ activity are Ca2+ entry and extrusion across the plasmalemma and Ca2+ release and uptake by the sarcoplasmic reticulum. To investigate the role of cytosolic Ca2+ in the proliferaton of VSMCs, we studied the proliferation and the dynamics of cytosolic Ca2+ in VSMCs from nondiabetic rats.
Methods
: The proliferation of aortic vascular smooth muscle cells of rats, acquired by enzymatic method, was studied with MTT assay, and calcium agonists (Bay K 8644 10(-6)M) or calcium antagonists(verapamil 10(-6)M). Cytosolic Ca2+ was measured by Fura 2 method.
Results
: Bay K 8644 enhanced VSMCs proliferation. Verapamil blocked the incremental effect induced by Bay K 8644. In the presence of extracellular calcium ion, Bay K 8644 (10(-6)M) abolished the increase in [Ca2+]i induced by Bay K 8644 in the presence of 1mM extracellular calcium ion.
Conclusion
: The enhanced proliferation of VSMCs is associated with the increment in cytosolic calcium.

MeSH Terms

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester
Animals
Atherosclerosis
Calcium
Cell Proliferation
Cytoplasm
Cytosol*
Fura-2
Muscle, Smooth, Vascular*
Rats
Sarcoplasmic Reticulum
Verapamil
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester
Calcium
Fura-2
Verapamil