Effects of remifentanil on intracellular Ca(2+) and its transients induced by electrical stimulation and caffeine in rat ventricular myocytes.
BACKGROUND
Preconditioning with remifentanil confers cardioprotection. Since Ca(2+) overload is a precipitating factor of injury, we determined the effects of remefentanil on intracellular Ca(2+) ([Ca(2+)](i)) and its transients induced by electrical stimulation and caffeine, which reflects Ca(2+) handling by Ca(2+) handling proteins, in rat ventricular myocytes.


METHODS
Freshly isolated adult male Sprague-Dawley rat myocytes were loaded with Fura-2/AM and [Ca](i) was determined by spectrofluorometry. Remifentanil at 0.1 - 1000 microg/L was administered. Ten minutes after administration, either 0.2 Hz electrical stimulation was applied or 10 mmol/L caffeine was added. The [Ca(2+)](i), and the amplitude, time resting and 50% decay (t(50)) of both transients induced by electrical stimulation (E [Ca(2+)](i)) and caffeine (C [Ca(2+)](i)) were determined.


RESULTS
Remifentanil (0.1 - 1000.0 microg/L) decreased the [Ca(2+)](i) in a dose-dependent manner. It also decreased the amplitude of both transients dose-dependently. Furthermore, it increased the time to peak and t(50) of both transients dose-dependently.


CONCLUSIONS
Remifentanil reduced the [Ca(2+)](i) and suppressed the transients induced by electrical stimulation and caffeine in rat ventricular myocytes.
Zhang
Ye
Y
Department of Anesthesiology, Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230601, China. zhangye_hassan@yahoo.com.cn
Irwin
Michael G
MG
Li
Rui
R
Chen
Zhi-Wu
ZW
Wong
Tak-Ming
TM
D000818:Animals; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects*; D002478:Cells, Cultured; D004558:Electric Stimulation; D008297:Male; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism*; D010880:Piperidines / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077208:Remifentanil
D010880:Piperidines; D002110:Caffeine; D000077208:Remifentanil; D002118:Calcium