Anotace:
Hibernating bats potentially risk cold-induced cell damage. However, the cells of hibernating bats have previously been shown to be able to cope with sub-zero temperatures, either alone or due to glucose cryoprotection. The aim of our study was to determine the survival rate of bat-derived cells in vitro after 24 h at −20 °C in a medium supplemented with urea at concentrations ranging from 0 to 320 mM or with a urea-glucose combination. Urea showed limited cryoprotective potential, with cell survival rates not exceeding 3% at urea concentrations of 20 to 40 mM, which corresponds to reported levels for blood urea in bats. Higher urea concentrations tended to be toxic rather than protective. Importantly, urea appeared to relieve delayed-onset cell death after cell rewarming, and also improved the cryoprotective effect of glucose up to three-fold. Thus, supplementation of cell cultures with a cryoprotectant mix containing urea could increase cell survival rates.