| Hippocampus CA3 pyramidal GLU cell | Middle apical dendrite | I L high threshold | . | In cell-attached patch-clamp recordings from the soma in guinea pig hippocampal slices, L-currents were found in 34% of the patches and found to have single channel conductances of 23-27 pS (Johnston D et al, 19921 ). (Fisher RE et al, 19902 ). Whole cell recording experiments have revealed a sustained, partially nimodipine-sensitve current in steps to -50mV, suggesting that they play a role in CA2+ signalling at low voltages as well as a their classical high voltages (Johnston D et al, 19921 ). It has been suggested that voltage-gated calcium channels play a role in LTP (Johnston D et al, 19921 ). and it has been shown that nimodipine (an L-channel antagonist) prevents certain mossy fiber LTP-types from taking place (Kapur A et al, 19983 ). |
| Hippocampus CA3 pyramidal GLU cell | Middle apical dendrite | I T low threshold | . | In cell-attached patch-clamp recordings from the soma in guinea pig hippocampal slices, T-currents were found in 72% of the patches and found to have single channel conductances of 8 pS (Johnston D et al, 19921 ). (Fisher RE et al, 19902 ). Whole cell recording from acutely isolated rat CA3 pyramidal neurons revealed a transient (59 msec decay time constant) that was inhibited by Ni2+ and amiloride (Avery RB and Johnston D, 1996 [rat]4 ). |
