[Inotropic effect of chlorpromazine on the frog atrium].
The chlorpromazine, a calmodulin inhibitor, has been studied for its action on the contraction force and calcium current of the frog atrium fibres. Chlorpromazine (10(-5) mol/l) was observed to induce maximal increase of the contraction force that 30 min after the agent action amounted to (47.3 + 9.3)% of control. The high concentration of chlorpromazine (10(-4) mol/l) produced irreversible decrease in the contraction force. Chlorpromazine (10(-5) mol/l) increased the calcium current by (27.5 +/- 4.8)%. It is supposed that chlorpromazine increases contraction force and calcium current through the inhibition of calmodulin-dependent phosphodiesterase activity.
Iuriavichius
I A
IA
Zablotskaĭte
D P
DP
Khmel'-Dunaĭ
G N
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D000818:Animals; D016275:Atrial Function; D002746:Chlorpromazine / Q000494:pharmacology*; D006325:Heart Atria / Q000187:drug effects; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*; D011895:Rana ridibunda; D013268:Stimulation, Chemical
D002746:Chlorpromazine
Inotropnoe deĭstvie khlorpromazina na predserdia liagushki.