Contractile function of papillary muscles with carbonic anhydrase inhibitors.
Contractile parameters of directly stimulated rabbit papillary muscles were studied during incubation in baths containing the carbonic anhydrase inhibitors chlorzolamide (1*10(-3) M) or ethoxzolamide (1*10(-4) M). Both inhibitors caused an at least partly reversible decrease in isometric force as it has been observed in skeletal muscle, and--in contrast to the results in skeletal muscles--a decrease in time-to-peak and half-relaxation time. It is postulated that inhibition of the membrane-bound carbonic anhydrase of heart muscle might induce an intracellular acidosis and that this acidosis causes the observed effects on contractile parameters.
Geers
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C
Zentrum Physiologie, Medizinische Hochschule, Hannover, F.R.G.
Gros
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G
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002257:Carbonic Anhydrase Inhibitors / Q000494:pharmacology*; D005016:Ethoxzolamide / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects* / Q000502:physiology; D010210:Papillary Muscles / Q000187:drug effects*; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D013830:Thiadiazoles / Q000494:pharmacology*
D002257:Carbonic Anhydrase Inhibitors; D013830:Thiadiazoles; C000471:chlorzolamide; D002118:Calcium; D005016:Ethoxzolamide