The effects of sodium-calcium exchange inhibitors on protein loss associated with the calcium paradox of the isolated Langendorff perfused guinea-pig heart.
The damage done to Langendorff perfused guinea-pig hearts by initiation of a calcium paradox, as assessed by the loss of myoglobin, is significantly reduced if inhibitors of Na(+)-Ca2+ exchange (Mn2+, Ni2+, bepridil and dodecylamine) are present when Ca2+ is repleted. This protection is not, to any major extent, due to secondary effects of these agents on the L-type Ca2+ channels, because more specific inhibitors of the Ca2+ channels are much less effective. These results suggest that the principal route for Ca2+ entry during the calcium paradox is Na(+)-Ca2+ exchange.
Chatamra
K R
KR
Department of Physiology, School of Veterinary Science, University of Bristol, UK.
Chapman
R A
RA
D000584:Amiloride / Q000031:analogs & derivatives / Q000494:pharmacology; D000588:Amines / Q000494:pharmacology; D000818:Animals; D015764:Bepridil / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism; D002352:Carrier Proteins / Q000037:antagonists & inhibitors* / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D066298:In Vitro Techniques; D017275:Isradipine / Q000494:pharmacology; D008297:Male; D008345:Manganese / Q000494:pharmacology; D009206:Myocardium / Q000378:metabolism*; D009211:Myoglobin / Q000378:metabolism*; D009532:Nickel / Q000494:pharmacology; D010477:Perfusion; D019831:Sodium-Calcium Exchanger
D000588:Amines; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D002352:Carrier Proteins; D004791:Enzyme Inhibitors; D009211:Myoglobin; D019831:Sodium-Calcium Exchanger; D008345:Manganese; D015764:Bepridil; D000584:Amiloride; D009532:Nickel; D002118:Calcium; C039614:ethylisopropylamiloride; D017275:Isradipine; C003935:dodecylamine