Involvement of vanilloid receptors in heat stress-induced delayed protection against myocardial ischemia-reperfusion injury.
Sprague-Dawley rats were pretreated with whole body hyperthermia (rectal 42 degrees C) for 15 min, 24 h before the experiments, and then the left main coronary artery of rat hearts was subjected to a 60 min occlusion followed by 3 h reperfusion. Myocardium injury degree was evaluated by measurement of infarct size and serum creatine kinase (CK) activity. Plasma concentrations of calcitonin gene-related peptide (CGRP), and the expression of alpha- and beta-CGRP mRNA in dorsal root ganglia were determined by radioimmunoassay and semi-quantitative reverse-transcription polymerase chain reaction, respectively. Hyperthermia treatment significantly reduced infarct size and CK release concomitantly with a dramatic increase in plasma concentrations of CGRP and the expression of alpha-CGRP mRNA, but not beta-CGRP mRNA, which was completely abolished by pretreatment with capsazepine (38 mg/kg, s.c.), a competitive vanilloid receptor 1 antagonist. These results suggests that vanilloid receptor 1 on capsaicin-sensitive sensory nerves plays an important role in the modulation of the delayed cardioprotection induced by heat stress in rats.
Hu
C-P
CP
Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, 410078, China.
Li
N-S
NS
Peng
J
J
Xiao
L
L
Deng
H-W
HW
Li
Y-J
YJ
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000097:blood / Q000235:genetics; D003402:Creatine Kinase / Q000097:blood; D005727:Ganglia, Spinal / Q000502:physiology; D018882:Heat Stress Disorders / Q000378:metabolism*; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000378:metabolism*
D012333:RNA, Messenger; D011955:Receptors, Drug; D003402:Creatine Kinase; D015740:Calcitonin Gene-Related Peptide