Intrahippocampal GMP administration improves inhibitory avoidance performance through GABAergic and glutamatergic mechanisms in rats.
Guanidino compounds play specific physiological and pathological roles in the central nervous system. We investigated the effect of an intrahippocampal infusion of GMP (a guanidino compound) administered immediately post-training on the inhibitory avoidance learning paradigm in rats. Bilateral intrahippocampal micro-injection of GMP (0-30 nmol) caused a dose-dependent increase in test step-down latencies which was completely reversed by intrahippocampal co-administration of muscimol or baclofen (GABA agonists) or preadministration (15 min pre-training, i.p.) of MK-801 (an NMDA antagonist). These results provide evidence for a participation of GABA and NMDA receptors in the GMP-induced increase in the test step-down latencies.
Rubin
M A
MA
Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, RS, Brasil.
Jurach
A
A
Zanolla
G R
GR
Boemo
R L
RL
Souza
D O
DO
de Mello
C F
CF
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects* / Q000502:physiology; D001418:Baclofen / Q000494:pharmacology*; D006152:Cyclic GMP / Q000008:administration & dosage / Q000494:pharmacology*; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D007839:Functional Laterality; D018755:GABA Agonists / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008845:Microinjections; D009118:Muscimol / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
D018755:GABA Agonists; D016194:Receptors, N-Methyl-D-Aspartate; D009118:Muscimol; D005680:gamma-Aminobutyric Acid; D016291:Dizocilpine Maleate; D006152:Cyclic GMP; D001418:Baclofen