Nitric oxide-induced inhibition on striatal cells and excitation on globus pallidus neurons: a microiontophoretic study in the rat.
Single units were recorded in the striatum and in the globus pallidus (GP) of urethane-anesthetized rats under microiontophoretic administration of either Nomega-nitro-L-arginine methyl ester (L-NAME, inhibitor of nitric oxide synthase), or 3-morpholino-sydnonimin-hydrocloride (SIN-1, nitric oxide, NO donor). A steady baseline firing of sporadically discharging striatal neurons (basal firing rate <0.1 spikes/s) was evoked by a pulsed microiontophoretic ejection of glutamate. On striatal neurons, microiontophoretic application of SIN-1 induced a current-dependent inhibition (11/13), whereas L-NAME administration produced a clear excitation (9/9). On GP cells, the administration of SIN-1 had excitatory effects (10/15), whereas the administration of L-NAME reduced the neuronal activity (6/6). We hypothesize that NO could exert an intrinsic regulatory action on the activity of both striatal and GP cells.
Sardo
Pierangelo
P
Dipartimento di Medicina Sperimentale--Sezione di Fisiologia umana, Università degli Studi di Palermo, Corso Tukory, 129-90134 Palermo, Italy.
Ferraro
Giuseppe
G
Di Giovanni
Giuseppe
G
La Grutta
Vittorio
V
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005917:Globus Pallidus / Q000187:drug effects* / Q000502:physiology; D018698:Glutamic Acid / Q000494:pharmacology; D007478:Iontophoresis / Q000379:methods*; D008297:Male; D008981:Molsidomine / Q000031:analogs & derivatives* / Q000494:pharmacology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology*
D004791:Enzyme Inhibitors; D014665:Vasodilator Agents; D009569:Nitric Oxide; D018698:Glutamic Acid; C002385:linsidomine; D008981:Molsidomine; D019331:NG-Nitroarginine Methyl Ester