Naloxone Blockade of Myocardial Ischemic Preconditioning is Stereoselective
| Autor: | G L Chien, D. M. Van Winkle |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
medicine.medical_specialty Ischemia Blood Pressure Naloxone Hydrochloride Bolus (medicine) Heart Rate Internal medicine medicine Animals Molecular Biology Endogenous opioid Cardioprotection Naloxone business.industry Stereoisomerism medicine.disease Endocrinology Opioid Coronary occlusion Anesthesia Ischemic Preconditioning Myocardial Ischemic preconditioning Rabbits Cardiology and Cardiovascular Medicine business medicine.drug |
| Zdroj: | Journal of Molecular and Cellular Cardiology. 28:1895-1900 |
| ISSN: | 0022-2828 |
| DOI: | 10.1006/jmcc.1996.0182 |
| Popis: | This study tested the hypothesis that endogenous opioids are involved in the infarct limitation of myocardial ischemic preconditioning (IP). Blockade of IP-induced infarct limitation by (-)naloxone hydrochloride (-NAL) or its receptor-inactive stereoisomer (+)naloxone (+NAL) was evaluated. Fifty-two pentobarbitone-anesthetized, open-chest rabbits underwent 30 min coronary artery occlusion and 180 min reperfusion. Treatment groups were: control (n = 9), i.p. (n = 8), -NAL (n = 9) and -NAL/i.p. (n = 12), or +NAL (n = 6) and +NAL/i.p. (n = 8). i.p. was elicited with 5 min regional ischemia, beginning 15 min before the 30 min coronary occlusion. -NAL or +NAL, 3 mg/kg i.v. bolus, was given 25 min before the 30 min coronary occlusion. Infarct size was assessed with tetrazolium and expressed as a percentage of area-at-risk. There were no significant intergroup differences of area-at-risk. IP resulted in marked infarct limitation compared to control (control, 32.9 +/- 7.6% v i.p., 5.8 +/- 4.5%; P = 0.04). Neither -NAL nor +NAL alone altered infarct size compared to control, but -NAL did block the infarct limitation of i.p. (-NAL, 31.4 +/- 6.7% v -NAL/i.p., 24.3 +/- 6.2%) whereas +NAL did not (+NAL, 40.5 +/- 5.0% v +NAL/i.p., 13.7 +/- 3.6%; P = 0.02). In conclusion, naloxone blockade of i.p.-induced cardioprotection is stereospecific and therefore likely to be opioid receptor-mediated. |
| Databáze: | OpenAIRE |
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