Involvement of atrial natriuretic peptide in abrogated cardioprotective effect of ischemic preconditioning in ovariectomized rat heart.
Hum Exp Toxicol
; 37(7): 704-713, 2018 Jul.
Article
in En
| MEDLINE
| ID: mdl-28920462
ABSTRACT
BACKGROUND:
Nitric oxide (NO) is an effective mediator of ischemic preconditioning (IPC)-induced cardioprotection. Atrial natriuretic peptide (ANP) is downregulated after ovariectomy, which results in reduction in the level of NO. The present study deals with the investigation of the role of ANP in abrogated cardioprotective effect of IPC in the ovariectomized rat heart.METHODS:
Heart was isolated from ovariectomized rat and mounted on Langendorff's apparatus, subjected to 30 min of ischemia and 120 min of reperfusion. IPC was given by four cycles of 5 min of ischemia and 5 min of reperfusion with Krebs-Henseleit solution. The myocardial infract size was estimated employing triphenyltetrazolium chloride stain, and coronary effluent was analyzed for creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) release to consider the degree of myocardial injury. The cardiac release of NO was estimated by measuring the level of nitrite in coronary effluent.RESULTS:
IPC-mediated cardioprotection was significantly attenuated in ovariectomized rat as compared to normal rat, which was restored by perfusion with ANP. However, this observed cardioprotection was significantly attenuated by perfusion with L-NAME, an endothelial nitric oxide synthase inhibitor, and Glibenclamide, a KATP channel blocker, alone or in combination noted in terms of increase in myocardial infract size, release of CK-MB and LDH, and also decrease in release of NO.CONCLUSION:
Thus, it is suggested that ANP restores the attenuated cardioprotective effect of IPC in the ovariectomized rat heart which may be due to increase in the availability of NO and consequent increase activation of mitochondrial KATP channels.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cardiotonic Agents
/
Myocardial Reperfusion Injury
/
Atrial Natriuretic Factor
/
Ischemic Preconditioning, Myocardial
/
Myocardial Infarction
Limits:
Animals
Language:
En
Journal:
Hum Exp Toxicol
Journal subject:
TOXICOLOGIA
Year:
2018
Document type:
Article
Affiliation country: