Possible mechanisms involved in the spontaneous rhythmicity in the guinea-pig tracheal smooth muscle as induced by glucose removal
Abe, M.; Furukawa, T.
Archives Internationales de Pharmacodynamie et de Therapie 261(1): 59-66
1983
ISSN/ISBN: 0003-9780 PMID: 6405706 Document Number: 198324
The rhythmic contraction induced by glucose removal was not eliminated by tetrodotoxin, atropine, propranolol or indomethacin, but was abolished by Ca2+ removal from the solution or administration of verapamil and was increased by Ca2+-ionophore (A-23187). The rhythmicity was eliminated by ouabain (1.7 X 10(-6) - 1.7 X 10(-5) M), and was also abolished by removal of potassium from the solution but re-appeared after re-admission of potassium. The addition of calcium or sodium to preparations incubated in calcium or sodium and glucose-free solution in the presence of ouabain did not induce rhythmicity. Our findings suggest that the rhythmicity produced by glucose removal in the guinea-pig tracheal smooth muscle is myogenic in origin and involves a depolarization-dependent calcium influx. The possibility that the rhythmicity may be related to alterations in Na-K ATPase activity was not ruled out.