Involvement of p38 MAPK and JNK in heat stress-induced cardioprotection.
The present study investigated whether heat stress-induced cardioprotection involves alterations in the pattern of p38 mitogen activated protein kinase (p38MAPK) and c-Jun NH2 - terminal kinase (JNK) activation during ischaemia - reperfusion in a model of isolated perfused rat heart. Wistar rats were subjected to whole-body hyperthermia at 42 degrees C for 15 min (HS), while untreated animals served as controls (CON). Twenty four hours later, CON and HS isolated hearts were perfused in a Langendorff mode and subjected to 20 min of zero-.ow global ischaemia followed by 45 min of reperfusion. Postischaemic recovery of left ventricular developed pressure at 45 min of reperfusion was expressed as % of the initial value (LVDP%). Activation of p38 MAPK and JNK was assessed by standard Western blotting techniques using a dual phospho-p38 MAPK and phospho-p46 JNK and p54 JNK antibodies. The levels of phospho-p38 MAPK at the end of reperfusion were not different in HS as compared to CON hearts. The levels of phospho-p46 JNK and p54 JNK were 1.4- and 1.6-fold less in HS than in CON hearts respectively, p < 0.05. LVDP% was 60.3 (s.e.m., 6.3) for HS and 42.9 (4.1) for CON, p < 0.05. In summary, heat stress pretreatment improves postischaemic recovery of function in isolated rat hearts and this is associated with suppressed JNK activation in response to ischaemia-reperfusion.
Pantos
Constantinos
C
Department of Pharmacology, University of Athens, 75 Mikras Asias Ave., 11527 Goudi, Athens, Greece. cpantos@cc.uoa.gr
Malliopoulou
Vassiliki
V
Mourouzis
Iordanis
I
Moraitis
Panagiotis
P
Tzeis
Stylianos
S
Thempeyioti
Anastasia
A
Paizis
Ioannis
I
Cokkinos
Alexandros
A
Carageorgiou
Hariclia
H
Varonos
Dennis D
DD
Cokkinos
Dennis V
DV
D000818:Animals; D004789:Enzyme Activation; D018882:Heat Stress Disorders / Q000378:metabolism* / Q000503:physiopathology; D048031:JNK Mitogen-Activated Protein Kinases; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009200:Myocardial Contraction; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000503:physiopathology; D009687:Nuclear Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015534:Trans-Activators / Q000378:metabolism*; D016277:Ventricular Function, Left; D017725:Ventricular Pressure; D048051:p38 Mitogen-Activated Protein Kinases; D000099251:Myocardin
D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D009687:Nuclear Proteins; D015534:Trans-Activators; D048051:p38 Mitogen-Activated Protein Kinases; D000099251:Myocardin