STIMULATION OF FROG CILIATED CELLS IN CULTURE BY ACETYLCHOLINE AND SUBSTANCE-P

1. Ciliary beat frequency in epithelial outgrowths from cultured explants of Rana pipiens palate changed markedly from second to second. 2. Acetylcholine (10(-8) to 10(-3) M) and substance P (1.35 x 10(-7) to 1.35 x 10(-5) M) increased and stabilized ciliary beat frequency. The effect of acetylcholine and part of the effect of substance P were blocked by atropine (10(-4) M). 3. Acetylcholine appears to act directly and substance P both directly and indirectly through the release of acetylcholine.