Pressure-controlled reperfusion improves postischemic recovery of LV-hypertrophied rat hearts.
The influence of pressure-controlled postischemic reperfusion (Rp) on functional and metabolic parameters in hearts of sham-operated rats and hypertrophied hearts of rats with aortic constriction were studied. Hypertrophied hearts are considered to be more susceptible to ischemia. The hearts were perfused in the Langendorff-technique for thirty minutes at 35 degrees C with Krebs-Henseleit bicarbonate buffer at a perfusion pressure (PP) of 75 mmHg and for five minutes at 15 degrees C with St. Thomas' Hospital cardioplegic solution at a PP of 60 mmHg. After a period of global ischemia of forty minutes' duration at 15 degrees C, reperfusion was started either abruptly (aRp: PP 75 mmHg immediately) or gently (gRp: PP 75 mmHg within thirty minutes); it lasted for forty-five minutes. Intraventricular peak systolic pressure (ISP) was monitored and energy-rich compounds (ATP, ADP, AMP, CrP, free Cr) were analyzed. In normal hearts, metabolic recovery was not affected by the mode of reperfusion, but functional recovery (ISP) averaged 88% of the preischemic control value after gRp as compared with 73% after aRp. In hypertrophied hearts, gentle reperfusion ameliorated both metabolic and functional recovery. At forty-five minute recovery, CrP averaged 5.1 mumol/g ww after aRp and 6.6 mumol/g ww after gRp (p less than 0.01), and ISP amounted to 73% of the preischemic control after aRp and to 85% after gRp.
Müller
C
C
Institute for Experimental Medicine, University of Cologne, West Germany.
Isselhard
W
W
Sturz
J
J
Wahle
A
A
Witmanowski
H
H
Armas-Molina
J V
JV
Saad
S
S
D000227:Adenine Nucleotides / Q000378:metabolism; D000818:Animals; D006332:Cardiomegaly / Q000378:metabolism / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D015425:Myocardial Reperfusion / Q000379:methods*; D010725:Phosphocreatine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D000227:Adenine Nucleotides; D010725:Phosphocreatine