Fig. 5.

Glutamate-induced endogenous Ca²⁺ mobilization requires ER-dependent Ca²⁺ release through InsP₃Rs. a The Ca²⁺ response to glutamate (100 µM) was inhibited by U73122 (10 µM, 30 min), a selective PLC blocker. Moreover, the Ca²⁺ signal was inhibited by blocking InsP₃Rs with 2-APB (50 µM, 30 min). b Emptying the ER Ca²⁺ pool with CPA (10 µM), a selective SERCA inhibitor, prevented the Ca²⁺ response to glutamate. As expected, CPA elicited a transient elevation in [Ca²⁺]_i due to the passive depletion of the ER Ca²⁺ pool followed by Ca²⁺ clearing through the plasma membrane and by mitochondria. c Bar histogram shows the mean ± SE of the percentage of responding cells under the designated treatments. The asterisk indicates that p < 0.05. d Bar histogram shows the mean ± SE of the amplitude of the Ca²⁺ response under the designated treatments. The asterisk indicates that p < 0.05. NR no response