Glutamate-induced activation of rat locus coeruleus increases CA1 pyramidal cell excitability.
In anesthetized rats, injections of a 0.5 mM glutamate solution into the locus coeruleus (LC) reversibly increased the amplitude of the population spike evoked in CA1 by stimulation of the Schaffer-commissural fiber tract. This effect was absent in N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4)-treated, noradrenaline (NA)-depleted animals. The excitatory postsynaptic potential recorded in the stratum radiatum was unaffected following the glutamate injections. Systemic administration of the NA-uptake inhibitor desipramine also produced an increase in population spike amplitude. The findings demonstrate that activation of LC neurons increases pyramidal cell excitability in vivo.
Olpe
H R
HR
Laszlo
J
J
Pozza
M F
MF
De Herdt
P
P
Waldmeier
P C
PC
Jones
R S
RS
D000818:Animals; D001596:Benzylamines / Q000494:pharmacology; D001931:Brain Mapping; D003891:Desipramine / Q000494:pharmacology; D005071:Evoked Potentials; D005971:Glutamates / Q000494:pharmacology*; D018698:Glutamic Acid; D006624:Hippocampus / Q000502:physiology*; D008125:Locus Coeruleus / Q000187:drug effects*; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D009638:Norepinephrine / Q000502:physiology*; D051381:Rats; D009435:Synaptic Transmission
D001596:Benzylamines; D005971:Glutamates; D018698:Glutamic Acid; C012102:DSP 4; D003891:Desipramine; D009638:Norepinephrine