Immunocytochemical localization of alpha-actinin in frog muscle treated with the ionophore A23187.
Incubation of frog skeletal muscle with the ionophore A23187 induces severe damage in the muscle. At the level of the Z line, the ionophore induces redistribution and release of the protein alpha-actinin, as shown by immunocytochemical techniques. The ionophore does not induce damage in denervated preparations or in preparations pretreated with d-tubocurarine, which indicates that the effect is indirect and neurally mediated. It is concluded that the increase in spontaneous transmitter release produced by the ionophore induces Ca2+ influx through the acetylcholine receptor. Calcium ions activate neutral proteases which release alpha-actinin from the Z line.
Llados
F T
FT
Department of Anatomy, University of Illinois, College of Medicine, Chicago.
Kriho
V
V
Pappas
G D
GD
D000185:Actinin / Q000378:metabolism*; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism; D009132:Muscles / Q000187:drug effects / Q000378:metabolism*; D011894:Rana pipiens; D011950:Receptors, Cholinergic / Q000378:metabolism
D015220:Calcium Channels; D011950:Receptors, Cholinergic; D000185:Actinin; D000001:Calcimycin; D002118:Calcium