Amnesic action of FMRFamide in rats.

The effects of FMRFamide on passive avoidance behaviour and electroshock-induced amnesia following intracerebroventricular administration were studied in rats. FMRFamide given immediately after the learning trial, or 20 min before the retention trial, attenuated the avoidance response, thereby impairing the consolidation and retrieval processes. Electroshock induced amnesia when applied immediately after the learning trial.

The effect of beta-(Tyr9)melanotropin-(9-18) on active avoidance behavior, electroconvulsive shock-induced amnesia and T-discrimination learning of rats.

The effect of beta-(Tyr9)melanotropin-(9-18) was investigated on active avoidance behavior, electroconvulsive shock (ECS)-induced amnesia and T-discrimination learning in rats. The decapeptide inhibited the extinction of active avoidance behavior. It was also able to block ECS-induced amnesia if the treatment was performed immediately, or 4 hr or 20 hr after the ECS.

Somatostatin and (D-Trp8, D-Cys14)-somatostatin delay extinction and reverse electroconvulsive shock induced amnesia in rats.

In the present study the effects of somatostatin and its analogs on active avoidance behavior, electroconvulsive shock (ECS)-induced retrograde amnesia, and spatial-discrimination learning were compared in rats. (D-Trp8, D-Cys14)-somatostatin (as did the somatostatin molecule itself) delayed the extinction of active avoidance behavior, antagonized ECS-induced amnesia, and did not modify spatial-discrimination learning. Des-Asn5-(D-Trp8, D-Ser13) somatostatin and des-AA1,2,4,5,12,13,-(D-Trp8) somatostatin did not influence these behaviors.

The role of the nucleus accumbens septi (NAS) in the behavioral action of beta-(Tyr9)melanotropin-(9-18).

In this study the effects of beta-(Tyr9)MSH-9-18 administered intracerebroventricularly (icv) or into the nucleus accumbens septi (NAS) were investigated on active and passive avoidance behavior of rats. This hypothalamic decapeptide in a dose of 1.0 microgram (icv) inhibited the extinction of active avoidance behavior however, in a dose of 0.

The role of central dopaminergic systems in the behavioral effects of H-Phe-Ile-Tyr-His-Ser-Tyr-Lys-OH.

In the present study the role of the central dopaminergic systems in the behavioral action of H-Phe-Ile-Tyr-His-Ser-Tyr-Lys-OH was investigated. The heptapeptide inhibited the extinction of active avoidance behavior if the treatment was performed intracerebroventricularly (icv) in a dose of 1 microgram, but was ineffective in a dose of 0.1 micrograms.