Preconditioned Coronary Effluent Cardioprotective in Rats
Rat hearts subjected to cycles of ischemia/reperfusion
MONDAY, Jan. 7 (HealthDay News) -- Preconditioned coronary effluent from hearts subjected to cycles of ischemia/reperfusion can protect naive acceptor hearts from ischemia/reperfusion injury, according to research published in the January issue of the American Journal of Physiology - Heart and Circulatory Physiology.
Lynn C. Huffman, M.D., and colleagues from the University of Cincinnati in Ohio, transferred warmed, oxygenated coronary effluent from rat hearts that had or had not experienced ischemia/reperfusion (preconditioning) to naive acceptor rat hearts in the presence or absence of inhibitors of the JAK-STAT signaling pathway. The acceptor hearts were then subjected to ischemia/reperfusion.
The researchers found that end-reperfusion +dP/dtmax and -dP/dtmin significantly improved in both donor and acceptor preconditioned hearts compared with non-preconditioned hearts. Donor and acceptor preconditioned hearts had significant increases in STAT-3 activation and decreases in pSTAT-1 and Bax expression. Treatment with a Jak 2 inhibitor attenuated the recovery of + and -dP/dt in acceptor hearts and significantly reduced the expression of pSTAT-3.
"Preconditioned coronary effluent activates JAK-STAT signaling, limits apoptosis and protects myocardial performance from ischemia/reperfusion injury," Huffman and colleagues conclude.