Mechanism of Ca2+ on the hyperthermia-induced apoptosis of rat hippocampal neurons in vitro

Abstract

To study the mechanism of Ca(2+) on the apoptosis induced by hyperthermia in neonate rat hippocampal neurons to provide the applicative evidence of dantrolene for preventing brain injuries. Dantrolene, Ca(2+) specific blocking agent, was used in the hyperthermia-induced apoptosis of primary hippocampal neurons in vitro to observe its effect on the apoptosis, fluorescent intensity, and dynamic change of Ca(2+) by flowcytometry and laser confocal microscopy. The rate of apoptosis was decreased significantly after hyperthermia treatment by dantrolene sodium. The intracellular Ca(2+) fluorescent intensity in 42 degrees C treatment group (107.35 +/- 6.0) was significantly lower than that in control group (159.12 +/- 33.8). The concentration of Ca(2+) began to decrease 20 approximately 25 s after adding dantrolene sodium, and reached the lowest level about 50 s later, and then kept lower than the basal level. Dantrolene sodium has an important protective effect on hippocampal neurons apoptosis induced by hyperthermia and may have some applicative value of preventing heat-induced brain injury.