Objective: To investigate the effect of Poria cocos, a Chinese medicinal herb, on cytosolic free calcium concentration ([Ca2+]i) in brain nerve cells of neonatal rats.
Methods: Double-wave-length fluorospectrophotometer and laser confocal scanning microscope were used to measure the [Ca2+]i in neurons.
Results: The water extract of poria (31-250 mg/L) induced a dose-dependent increase in [Ca2+]i, but poria at the range of 500 mg/L did not cause [Ca2+]i to increase. It was also shown that the water extract of poria significantly inhibited the increment of [Ca2+]i induced by 500 mumol/L glutamate. The similar results were observed from the experiments in primarily cultured hippcampal neurons of neonatial rats by using laser confocal scanning microscope.
Conclusions: The water extract of Poria cocos has the effect of bidirectional regulation on cytosolic free calcium in brain nerve cells.