Pharmacological dissection of high-voltage-activated (HVA) whole-cell Ca²⁺ current types in rat cerebellar granule neurons. A, L- and N-type currents were isolated by application of 10 μM nimodipine or 1 μM ω-conotoxin-GVIA (ω-CTx-GVIA), respectively. P- and Q-type currents were isolated by application of 1.5 nM or 1-3 μM ω-agatoxin-IVA (ω-Aga-IVA), respectively. R-type current was isolated by combined application of nimodipine, ω-CTx-GVIA and ω-Aga-IVA. B, summary of the current densities and relative contributions of each current type, determined from the data in A. Adapted from Randall and Tsien (1995).⁷⁴