Effects of a substance P-analogue on blood pressure and avoidance learning of rats with spontaneous hypertension.
A shortened and modified eledoisin-hexapeptide sequence (Lys-Phe-Ile-Gly-Leu-MetNH2) was tested for their action on avoidance learning and blood pressure of rats with spontaneous hypertension (SH-rats) and intact Wistar rats. Both groups were 10, 14, and 26 weeks of age. Disorders of avoidance learning and elevation of blood pressure were likely to aggravate along with growing age of SH-rat. The used eledoisin-hexapeptide sequence is related to the essential C-terminal pentapeptide sequence of Substance P (SP). After injection of the used hexapeptide at doses of 250 microgram/kg intraperitoneally disorders in avoidance learning were completely eliminated from ten-week SH-rats or conditionally for SH-rats aged 14 and 26 weeks. Elevated blood pressure in SH-rats aged 26 weeks was reduced by the hexapeptide from 220 Torr to approximately 190 Torr. Blood pressure in SH-rats aged 14 weeks, originally about 180 Torr, was almost unaffected by the hexapeptide. Blood pressure went up from about 150 Torr to 190 in ten-week-old Sh-rats. A hypothesis was made about the mode of action of Substance P and related peptides.
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects*; D004600:Eledoisin / Q000031:analogs & derivatives* / Q000494:pharmacology; D006973:Hypertension / Q000503:physiopathology*; D051381:Rats; D011919:Rats, Inbred Strains
D004600:Eledoisin