[The role of sarcolemma calcium pump in regulating tonic smooth muscle contraction].
Vanadate (10(-4)-10(-3) M) effectively blocks Mg2+, ATP-dependent Ca2+ transport in sarcolemmal vesicles and induces a slowly tonic contraction of the smooth muscle. This contraction was observed both with and without nifedipine (10(-5) M) evoking complete inhibition of hyperpotassium contracture, the Ca2+ removal from the solution washing the muscular preparation stimulating the tone decrease. There is a close correlation between the dose-dependent effects of vanadate on the Ca pump activity and tension. It is concluded that in smooth muscles, at least in myometrium, the sarcolemmal Ca-pump is involved into the control of the tonic tension.
Kosterin
S A
SA
Burdyga
F V
FV
Chervonenko
I V
IV
Burchinskaia
N F
NF
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D005260:Female; D008274:Magnesium / Q000037:antagonists & inhibitors; D009130:Muscle, Smooth / Q000378:metabolism*; D009215:Myometrium / Q000378:metabolism; D011817:Rabbits; D012508:Sarcolemma / Q000187:drug effects / Q000378:metabolism*; D014638:Vanadates / Q000494:pharmacology
D014638:Vanadates; D000255:Adenosine Triphosphate; D008274:Magnesium; D002118:Calcium
Rol' kal'tsievogo nasosa sarkolemmy v reguliatsii tonicheskogo sokrashcheniia gladkoĭ myshtsy.