Pharmacological control of ciliary activity in the young sea urchin larva. Studies on the role of Ca2+ and cyclic nucleotides.
The ciliary stimulation by monoamines is enhanced by adenylcyclase activators and a phosphodiesterase inhibitor indicating that cAMP is a mediator, a conclusion supported by the effects of db-cAMP. The role of cGMP is also examined. When stimulation exceeds certain levels, it is overpowered by some inhibitory feedback mechanism. The effects of altered Ca2+ concentrations, Ca2+ antagonists and a Ca2+ ionophore suggest that Ca2+ is involved in ciliary excitation as well as in the inhibitory mechanism. These suggestions are examined by experiments on the influence of altered Ca2+ concentrations and of the phosphodiesterase inhibitor on the response to various agents.
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001679:Biogenic Amines / Q000378:metabolism; D003994:Bucladesine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology*; D002923:Cilia / Q000187:drug effects*; D000242:Cyclic AMP / Q000502:physiology*; D006152:Cyclic GMP / Q000502:physiology*; D003995:Dibutyryl Cyclic GMP / Q000494:pharmacology; D007814:Larva / Q000502:physiology; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D012617:Sea Urchins / Q000502:physiology*
D001679:Biogenic Amines; D010726:Phosphodiesterase Inhibitors; D003995:Dibutyryl Cyclic GMP; D003994:Bucladesine; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D006152:Cyclic GMP; D011188:Potassium; D002118:Calcium; D015056:1-Methyl-3-isobutylxanthine