Effect of acetylcholine and ischaemia/reperfusion injury on the heart of rats with STZ-induced experimental diabetes.
OBJECTIVE
To investigate the effect of acetylcholine (ACh) and ischaemia/reperfusion injury on functional changes and dysrhythmias of the isolated diabetic rat heart.


RESULTS
On retrogradely perfused hearts isolated from 10-week-old diabetic rats (streptozotocin 30 mg/kg b.w. for three consecutive days i.p.), two types of experiments were done: /1/ The effect of acetylcholine (ACh; 3 x 10(-7) mol/l) was evaluated both during and after infusion, and /2/ the influence of the ischaemia/reperfusion injury (I/R) was studied. At the end of both experiments the hearts were electrically stimulated to evoke sustained ventricular fibrillation (VF). An increase of coronary arterial pressure, bradycardia and decreased total number of severe dysrhythmias of both types, spontaneous and evoked ones, were recorded in the diabetic hearts. ACh increased the force of contraction (LVP) and induced vasoconstriction, which persisted in the diabetic hearts even after removal of ACh from the perfusion solution.


CONCLUSIONS
The isolated diabetic rat heart was more resistant against severe dysrhythmias. After washing out the ACh, the vasoconstriction of coronary arteries still lasted, along with increased inotropic effect on the left ventricle.
Knezl
Vladimír
V
Institute of Experimental Pharmacology, Slovak Academy of Sciences, Bratislava, Slovakia. exfaknem@savba.sk
Kysel'ová
Zuzana
Z
Zúrová-Nedelcevová
Jana
J
Navarová
Jana
J
Tribulová
Narcis
N
Drímal
Jan
J
D000109:Acetylcholine / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000473:pathology*; D003925:Diabetic Angiopathies / Q000150:complications / Q000473:pathology; D005071:Evoked Potentials / Q000187:drug effects; D006321:Heart / Q000187:drug effects*; D008297:Male; D017202:Myocardial Ischemia / Q000150:complications / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000150:complications / Q000473:pathology*; D013311:Streptozocin; D014665:Vasodilator Agents / Q000494:pharmacology; D014693:Ventricular Fibrillation / Q000473:pathology
D014665:Vasodilator Agents; D013311:Streptozocin; D000109:Acetylcholine