Fig. 4. ISIT is regulated by the activity of mGluR1, T-type Ca2+ channel and ER store. The PC has strict ISIT to restrict unnecessary dendritic Ca2+ transient. Normally, the ISIT of the PC is less than 4 ms, requiring firing frequencies above 200 Hz to induce dendritic Ca2+ transients. However, activation of mGluR1 can loosen the ISIT to over 19 ms, equivalent to firing frequencies lower than 50 Hz. On the other hand, blocking T-type calcium channels or depleting the endoplasmic reticulum stores can tighten the ISIT to less than 2 ms, equivalent to firing frequencies above 333 Hz.
© Exp Neurobiol