Protective effects of calpain inhibitor for prolonged hypothermic cardiac preservation.
OBJECTIVE
For successful organ transplantation, it is important to properly preserve the donor organ. This study was carried out to investigate tissue damage generated by the activation of calpain during prolonged hypothermic cardiac preservation using specific antibodies for mu- and m-calpain proenzymes, and to ensure the protective effect of calpain inhibitor 1 (N-acetyl-leucyl-leucyl-norleucinal).


METHODS
Excised rat hearts were divided into two groups: in Group I, the heart was arrested and immersed in University of Wisconsin solution with 20 microM of calpain inhibitor 1 (n = 28) and in Group N, the heart was arrested and immersed in University of Wisconsin solution without calpain inhibitor (n = 27). After a 12-hour preservation period at 4 degrees C, the hearts were reperfused on an isolated perfusion apparatus. Separation of the myocardial calpain isozymes was carried out by DEAE cellulose chromatography and both calpain proenzymes were detected by immunoblotting.


RESULTS
The cardiac function was more satisfactorily maintained in Group I in comparison with Group N. Remarkable leakage of creatine kinase, glutamic-oxaloacetic transaminase and lactate dehydrogenase was detected in Group N, while it was efficiently suppressed in Group I. During ischemia, mu-calpain proenzyme decreased in Group N (p < 0.01), but there was no significant change in m-calpain. However, during reperfusion, both mu- and m-calpains decreased more in Group N (p < 0.01).


CONCLUSIONS
Activation of calpain proenzymes and a decrease in cardiac function during preservation and reperfusion were demonstrated. The use of calpain inhibitor to protect against tissue damage was suggested as being useful for the prolonged preservation of the heart.
Saito
T
T
Division of Cardiovascular Surgery, Nagoya City University Medical School, Japan.
Mishima
A
A
Asano
M
M
Ukai
T
T
Yamamoto
S
S
Kunimatsu
M
M
Sasaki
M
M
Manabe
T
T
D000241:Adenosine; D000493:Allopurinol; D000818:Animals; D000906:Antibodies; D002154:Calpain / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000276:immunology; D004792:Enzyme Precursors / Q000032:analysis / Q000276:immunology; D005978:Glutathione; D006321:Heart / Q000502:physiology*; D016027:Heart Transplantation; D007036:Hypothermia, Induced; D007328:Insulin; D007976:Leupeptins / Q000494:pharmacology*; D008297:Male; D009926:Organ Preservation / Q000379:methods*; D019188:Organ Preservation Solutions; D011887:Raffinose; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D000906:Antibodies; D004792:Enzyme Precursors; D007328:Insulin; D007976:Leupeptins; D019188:Organ Preservation Solutions; C055206:University of Wisconsin-lactobionate solution; C063261:acetylleucyl-leucyl-norleucinal; D000493:Allopurinol; D002154:Calpain; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose