Effect of K+ channel blockers on anti-immunoglobulin-induced murine B cell proliferation.

Ion channels play an important role in the transmission of signals across cell membrane in a variety of cell types. Recent studies indicate that normal murine splenic B lymphocytes express voltage gated K+ channels. In the present study, we examined the influence of K+ channel blockers 4 aminopyridine (4 AP) and tetraethyl ammonium, and Ca++ activated K+ channel blocker quinine on anti-immunoglobulin (anti-Ig)-induced B cell proliferation. The results show that ion channel blockers inhibited DNA synthesis in B cells induced by anti-Ig. 4 AP also inhibited protein synthesis but had no effect on the expression of surface immunoglobulin. 4 AP exerted its maximum suppressive effects on DNA synthesis when added within the first 24 hours after the onset of culture with anti-Ig. The inhibition of DNA synthesis by 4 AP was reversible upon its removal from culture. These studies show a role of K+ channels in B cell DNA and protein synthesis.