153. Fisher RE, Gray R and Johnston D. (1990) Properties and distribution of single voltage-gated calcium channels in adult hippocampal neurons. J Neurophysiol 64:91-104 [Journal] .

NeuronCompartmentPropertyConnectivityNotes
Hippocampus CA3 pyramidal cellMiddle apical dendriteI 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, 1992160 ; Fisher RE et al, 1990153 ). 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, 1992160 ). It has been suggested that voltage-gated calcium channels play a role in LTP (Johnston D et al, 1992160 ), and it has been shown that nimodipine (an L-channel antagonist) prevents certain mossy fiber LTP-types from taking place (Kapur A et al, 1998161 ).
Hippocampus CA3 pyramidal cellMiddle apical dendriteI 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, 1992160 ; Fisher RE et al, 1990153 ). 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 ]149 ).
Hippocampus CA3 pyramidal cellSomaI 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 et al. 1992; Fisher RE et al, 1990153 ). 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 (Avery RB and Johnston D, 1996 [rat ]149 ). It has been suggested that voltage-gated calcium channels play a role in LTP (Johnston et al. 1992), and it has been shown that nimodipine (an L-channel antagonist) prevents certain mossy fiber LTP-types from taking place (Kapur A et al, 1998161 ).
Hippocampus CA3 pyramidal cellSomaI N.In cell-attached patch-clamp recordings from the soma in guinea pig hippocampal slices, N-currents were found in 63% of the patches and found to have single channel conductances of 14 pS (Johnston et al. 1992; Fisher RE et al, 1990153 ). Bath application of omega-conotoxin MVIIC blocked (with rapid kinetics) approximately 20% of the high-voltage activated Ca2+ current, suggesting the presence of N-channels measured in whole-cell recordings (McDonough SI et al, 1996 [rat ]166 ).
Hippocampus CA3 pyramidal cellSomaI 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 et al. 1992, Fisher RE et al, 1990153 ). 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 ]149 ).

References
160. Johnston D, Fisher R and Gray R. (1992) Voltage-gated calcium channels in adult hippocampal neurons. Ion Channels 3:39-62.
153. Fisher RE, Gray R and Johnston D. (1990) Properties and distribution of single voltage-gated calcium channels in adult hippocampal neurons. J Neurophysiol 64:91-104 [Journal] .
161. Kapur A, Yeckel MF, Gray R and Johnston D. (1998) L-Type calcium channels are required for one form of hippocampal mossy fiber LTP. J Neurophysiol 79:2181-90.
149. Avery RB and Johnston D. (1996) Multiple channel types contribute to the low-voltage-activated calcium current in hippocampal CA3 pyramidal neurons. J Neurosci 16:5567-82.
166. McDonough SI, Swartz KJ, Mintz IM, Boland LM and Bean BP. (1996) Inhibition of calcium channels in rat central and peripheral neurons by omega-conotoxin MVIIC. J Neurosci 16:2612-23.
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