Calcium and cardioplegia in neonates: Dose-response and time-response studies in rats

E. Riva, D. J. Hearse

Research output: Contribution to journalArticle

Abstract

Isolated Langendorff-perfused rat hearts (n = 6/group) were subjected to 60, 90, 120, or 180 min of ischemia with or without a 2-min preischemic infusion with St. Thomas' Hospital cardioplegic solution that had been modified to contain concentrations of calcium of 0, 0.5, 0.8, 1.0, 1.2, 1.8, or 2.4 mM. In general, irrespective of the calcium concentration, hearts in the cardioplegia group recovered better than those in the non-cardioplegia group. There was no consistent relationship between calcium content and postischemic recovery of function or enzyme leakage after any of the durations of ischemia studied. However, as expected, there was a strong inverse relationship between recovery and duration of ischemia. The recovery of function correlated with enzyme leakage but not with the time to onset or magnitude of ischemic contracture. In conclusion, although the neonatal rat heart benefits from cardioplegia the protection is less impressive than that reported for adult hearts. Nonetheless, the neonatal heart appears to be very resistant to ischemia. We propose that many of these differences can be explained on the basis of differences in myocardial calcium handling between neonate and adult.

Original languageEnglish
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume261
Issue number5 30-5
Publication statusPublished - 1991

Keywords

  • Contracture
  • Heart
  • Ischemia
  • Reperfusion

ASJC Scopus subject areas

  • Physiology

Fingerprint Dive into the research topics of 'Calcium and cardioplegia in neonates: Dose-response and time-response studies in rats'. Together they form a unique fingerprint.

  • Cite this