Effect of nifedipine on core cooling in rats during tail cold water immersion

摘要

Male rats (450 g, n = 11/group) were heated at an ambient temperature of 42degreesC until a rectal temperature of 42.8degreesC was attained. Rats, then received either saline (30degreesC) + tail ice water immersion (F + I) or saline (30degreesC) + tail ice water immersion + Nifedipine, a peripheral vasodilator, (F + I + N) to determine cooling rate effectiveness and survivability. The time to reach a rectal temperature of 42.8degreesC averaged 172 min in both groups resulting, in similar heating rates (0.029degreesC/min). The cooling rates in group F + I and F + I + N were not significantly different from each other. We conclude that since Nifedipine did not improve cooling rates when combined with fluid + tail ice water immersion, its use as a cooling adjunct does not seem warranted