The effect of repeated diazepam administration on myocardial function in the ischemia-reperfused isolated rat heart.
OBJECTIVE
To evaluate whether repeated diazepam administration affects the heart in ischemia-reperfusion.


METHODS
This study was performed at the Medical Biology Research Center, Kermanshah, Iran, from March to September 2008. Four groups of rats were subjected to a daily injection of diazepam (group 1 [0.5 mg/kg for 21 days], group II [2.5 mg/kg for 5 days], and group III [5 mg/kg for 5 days] intraperitoneally), and saline solution (21 days) in the control groups. Isolated, perfused hearts were subjected to 40 minutes global ischemia, and 45 minutes reperfusion. The left ventricular developed pressure (LVDP), heart rate, and coronary flow were measured. Rate pressure product (RPP) was calculated. In reperfusion, released lactate dehydrogenase (LDH) enzyme in effluent was measured.


RESULTS
It was observed that the recovery of the RPP and LVDP in reperfusion significantly decreased in the test group III (n=9) in comparison to the control (n=8). During the reperfusion period, the released LDH significantly increased in test group II (n=8) and group III in comparison with the control.


CONCLUSIONS
The results show that repeated administration of diazepam (5 mg/kg for 5 days) reduced the cardiac performance in reperfusion, and significantly exacerbated the ischemia-reperfusion injury. It is probably mediated by the changing of cardiac susceptibility in ischemia due to repeated administration of diazepam.
Shackebaei
Dareuosh
D
Department of Physiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran. dshakebaei@kums.ac.ir
Kayhani
Bijan
B
Godini
Aliashraf
A
Pourshanazari
Aliasghar
A
Reshadat
Sohyla
S
D000818:Animals; D003975:Diazepam / Q000008:administration & dosage* / Q000494:pharmacology; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000503:physiopathology*
D003975:Diazepam