Nitric oxide donors, sodium nitroprusside and S-nitroso-N-acetylpenicillamine, stimulate myoblast proliferation in vitro

Nitric oxide (NO) is an inter- and intracellular messenger involved in a va riety of physiologic and pathophysiologic conditions. The effect of two NO donors, sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine (SNA P) and their effect on myoblast proliferation was examined. Both donors sti mulated an increase in myoblast cell number over a range (1-10 mu M) of don or concentrations. However, 50 mu M SNAP inhibited myoblast proliferation. Cell numbers from cultures treated with degraded 10 mu M SNAP were equivale nt to the control. Therefore, it appears NO call stimulate as well as inhib it myoblast proliferation.