[Significance of the time of administering substance P on learning and memory in rats].

We studied the influence of time and period of application of substance P (SP) on type and size of the effects on learning in Wistar rats. Treatment with SP before acquisition training had a fascillitating effect on learning. If SP was applied from the 1st or 3rd d of acquisition training there was no effect; if given from the 2nd d an inhibition was found; if given from the 4th d the consolidation of memory became finished.

[Neuropeptides in regulation].

1. The thyroid gland is regulated on nerval and neurohormonal way by the hypothalamus, in which case the hypothalamus is regarded as one of the most important limbs in the chain of the limbic system. 2.

[Effect of a substance P analog on sleep deprivation].

The injection of 250 microgram/kg SP-analogue (Lys-Phe-Ile-Gly-Leu-MetNH2) is able to restore the reduced or disturbed delta activities and paradoxical sleep periods of the sleeping EEG in chronically stressed rats. Thus it has been proved that Substance P, which we would like to term as an ,,regulatory peptide" (equal to regulide) has a modulating function.