|
1000126375
|
Neurons IonicCurrents
68 records
|
N-methyl-D-aspartate receptors (NMDARs) blocked the initiation of dendritic
action potentials (Fig. 6A and B), and attenuated the peak amplitude of the
associated [Ca2+]i transients (Fig. 6C and D; n=9). Initiation of both Ca2+
action potentials by distal synaptic stimulation and the associated [Ca2+)i
transients were completely blocked by addition of the
alfa-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPAR)
antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 10 µM) to the
extracellular solution (Fig. 6 B and D; n=3). CNQX also reduced the amplitude
of synaptically evoked composite PSPs in dendrites and the soma (not
shown)."p.611
"The dependence of local distal dendritic action potential initiation and the
associated [Ca2+]i transient on activation of NMDA receptors probably resulted
from the relatively slow activation and inactivation kinetics of NMDA
receptors. Thus, it is possible that a train of AMPA-mediated EPSPs could also
evoke Ca2+ actio potentials in distal apical dendrites."p.611
