The Relationship between Spontaneous Calcium Oscillations and Cell Proliferation in Cultured Smooth Muscle Cells

Abstract

The relationship between spontaneous Ca²⁺ oscillations and cell proliferation was investigated in cultured longitudinal muscle cells from guinea pig ileum. BAPTA, caffeine, thapsigargine and La³⁺ suppressed the spontaneous Ca²⁺ oscillations and the DNA synthesis at 5.0 mM, 10.0 mM, 15.62 nM and 0.5 mM, respectively, whereas verapamil, nicardipine and ryanodine did not suppress either. However, BAPTA and La³⁺ did not inhibit the DNA synthesis at 1.25 mM and 0.13 mM, but did suppress the Ca²⁺ oscillations even at 1.0 mM and 0.1 mM, respectively. These results show that the spontaneous Ca²⁺ oscillations are not prerequisite for the cell proliferation.