EFFECTS OF VOLATILE ANESTHETICS ON PH ACTIVITY AND ISCHEMIC-REPERFUSION INJURY IN MYOCARDIAL CELLS

2002 Fiscal Year Final Research Report Summary

• Project/Area Number: 11470320
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Anesthesiology/Resuscitation studies
• Research Institution: UNIVERSITY OF YAMANASHI (FACULTY OF MEDICINE)
• Principal Investigator: KUMAZAWA Teruo UNIVERSITY OF YAMANASHI, FACULTY OF MEDICINE, PROFESSOR, 医学部, 教授 (10092404)
• Co-Investigator(Kenkyū-buntansha): OGUCHI Takeshi UNIVERSITY OF YAMANASHI, FACULTY OF MEDICINE, ASSISTANT PROFESSOR, 医学部, 講師 (60201399)
• Project Period (FY): 1999 – 2002
• Keywords: MYOCYTES / PH ACTIVITY / VOLATILE ANESTHETICS / REPERFUSION INJURY / H^+交換系

Research Abstract

We studied the effects of volatile anesthetics on pH activity in myocardial cells during ischemic-reperfusion injury. In this study, we examined pH activity, Ca2+ transients, and contractility in isolated rabbit ventricular myocytes. Intracellular H+ concentration (pHi), Na+ concentration ([Na+]i) and Ca2+ concentration ([Ca2+]i) were measured with the fluorescent pH indicators (BCFCE), Na+ indicators (SBFI) and Ca2+ indicators (Fluo-3), respectively. Contractility was assessed from changes in cell shortening during field stimulation. Experiments were performed at extracellular pH 7.4 in the presence of HEPES buffer. Our findings demonstrate that 1) halothane significantly decreased contractility compared with isoflurane, 2) halothane and isoflurane attenuate the magnitude in decreases in pHi during reperfusion, 3) halothane and isoflurane attenuate the magnitude in decreases in pHi during ischemic period. It is suggested that a reduction of excessive intracellular hydrogen after reperfusion caused by halothane and isoflurane may be beneficial on myocardial function following reperfusion in the intact rabbit myocardium.