Background:

[Sar9,Met(O2)11]-Substance P is a tachykinin NK1 receptor selective agonist.
[Sar9,Met(O2)11]-Substance P and septide (10-100?pmol per rat, i.c.v.) are equipotent in increasing mean arterial blood pressure (MAP) and heart rate (HR), yet they have dissimilar time-course. Both agonists increase dose-dependently face washing and sniffing while [Sar9,Met(O2)11]-Substance P is the sole to produce grooming[1].
Reference:
[1]. Cellier E, et al. Characterization of central and peripheral effects of septide with the use of five tachykinin NK1 receptor antagonists in the rat. Br J Pharmacol. 1999 Jun;127(3):717-28.