Temperature-dependent cardioprotection of exogenous substrates in long-term heart preservation with continuous perfusion: twenty-four-hour preservation of isolated rat heart with St. Thomas' Hospital solution containing glucose, insulin, and aspartate.
METHODS
Using an isolated working rat heart model, we determined the effects of glucose, insulin, and aspartate on recovery of cardiac function when used as components of preservation solution at different temperatures. After measurement of baseline cardiac function, hearts (n = 6 per group) were perfused with oxygenated St. Thomas' Hospital solution containing (1) vehicle, glucose (9 mmol/L) or aspartate (20 mmol/L) for 12 hours at either 20 degrees or 4 degrees C; (2) glucose or glucose + insulin (10 U/L) at 20 degrees C for 20 hours; and (3) glucose + insulin at 20 degrees C or glucose + insulin + aspartate at either 20 degrees or 4 degrees C for 24 hours. Cardiac function was measured after preservation and expressed as a percentage of baseline values.


RESULTS
At 20 degrees C, both glucose and aspartate increased recovery of cardiac output (vehicle, 57.7% +/- 3.8%; glucose, 76.5% +/- 2.4% [p < 0.05 versus vehicle]; aspartate, 79.9% +/- 1.4% [p < 0.05 versus vehicle]). At 4 degrees C, glucose decreased recovery of cardiac output, whereas aspartate did not change the value (vehicle, 74.4% +/- 2.2%; glucose, 61.4% +/- 2.8% [p < 0.05 versus vehicle]; aspartate, 80.5% +/- 1.7%). The addition of insulin to glucose increased recovery of cardiac output (glucose, 24.6% +/- 4.0%; insulin + glucose, 69.2% +/- 2.0%: p < 0.05). The combined use of these three agents showed an additive effect in improvement of recovery of cardiac output at 20 degrees C (glucose + insulin, 64.2% +/- 2.2%; glucose + insulin + aspartate, 76.0% +/- 1.1%; p < 0.05), but the recovery at 4 degrees C (63.1% +/- 1.8%) was significantly lower than at 20 degrees C.


CONCLUSIONS
These results suggest that glucose and aspartate afford differential cardioprotective effects depending on the temperature of the preservation solution and that combined use of glucose, insulin, and aspartate at the optimal temperature may extend graft preservation time.
Shimada
Y
Y
Second Department of Surgery, Kyoto Prefectural University of Medicine, Japan.
Yamamoto
F
F
Yamamoto
H
H
Oka
T
T
Kawashima
Y
Y
D000818:Animals; D001224:Aspartic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D001639:Bicarbonates / Q000008:administration & dosage / Q000627:therapeutic use; D001834:Body Water / Q000737:chemistry; D002122:Calcium Chloride / Q000008:administration & dosage / Q000627:therapeutic use; D002302:Cardiac Output / Q000187:drug effects; D002314:Cardioplegic Solutions / Q000008:administration & dosage / Q000627:therapeutic use*; D003326:Coronary Circulation; D003402:Creatine Kinase / Q000032:analysis; D015925:Cryopreservation; D005947:Glucose / Q000008:administration & dosage / Q000627:therapeutic use*; D016027:Heart Transplantation / Q000502:physiology; D007328:Insulin / Q000008:administration & dosage / Q000627:therapeutic use*; D008274:Magnesium / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D009206:Myocardium / Q000737:chemistry / Q000201:enzymology; D009926:Organ Preservation; D010477:Perfusion; D011189:Potassium Chloride / Q000008:administration & dosage / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride / Q000008:administration & dosage / Q000627:therapeutic use; D013696:Temperature; D013997:Time Factors
D001639:Bicarbonates; D002314:Cardioplegic Solutions; D007328:Insulin; C041711:St. Thomas' Hospital cardioplegic solution; D001224:Aspartic Acid; D012965:Sodium Chloride; D011189:Potassium Chloride; D003402:Creatine Kinase; D008274:Magnesium; D005947:Glucose; D002122:Calcium Chloride