Isolated cardiac muscle performance during fluorocarbon immersion and effects of metabolic blockade.

Abstract

SummaryThe mechanical performance of isolated trabecular muscle preparations from the left ventricle of rats was evaluated while immersed in Krebs-Henseleit and fluorocar-bon solution under oxygenated conditions and during hypoxia and total metabolic blockade with combined hypoxia and iodoa-cetic acid 10-4M. Under oxygenated conditions, mechanical performance was relatively stable in both Krebs-Henseleit and fluorocar-bon solutions for 60 minutes. With glycolytic blockade, performance in both groups was relatively stable, although it was significantly increased in fluorocarbon solution in comparison to Krebs-Henseleit solution at 60 min (P < 0.01). With total metabolic blockade, mechanical performance fell to zero within 10 min in both Krebs-Henseleit and fluorocarbon solution. With hypoxia alone, mechanical performance declined more promptly and remained at lower levels in fluorocarbon solution than in Krebs-Henseleit solution (P < 0.001).