Effects of TRPC Blockers on eCB Signaling 143 Ca-RER can be induced by 1 μM or higher concentration of calcium [22]. Therefore, if calcium increase induced by VOCC was more than 1 μM and hence sufficient to mediate endocannabinoid release, TRPC-mediated calcium increase could be overwhelmed by the activation of VOCC. Thus, a possibility that TRPC can contribute to endocannabinoid release in the condition that VOCC activates to a lesser degree still remains. However, the amplitude of endocanna- binoid-induced depression increases in a calcium dependent manner to almost 80% of control, up to calcium concen- trations of 5 μM [22]. The amplitude of attenuation of EPSC we observed was about 50%, which is not maximal degree of endocannabinoid-mediated depression. If TRPC contributes to endocannabinoid release, BTP2 should in- hibit the depression of EPSC at least partially in spite of VOCC. Therefore, our data suggest TRPC is not involved in endocannabinoid release. 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