Xenin 8 acetate is a biologically active fragment of Xenin in the neurotensin/xenopsin family. Xenin 8 acetate augments Arginine-induced insulin release (by 40%) and potentiates the glucagon responses to both Arginine (by 60%), Carbachol (by 50%).

Galanin is a neuropeptide with diverse biological activities. [1][2][3][4][5] It binds to rat galanin (GAL) receptor subtypes GAL1-3 (IC50s = 0.339, 1.35, and 3.31 nM, respectively) and human GAL1-3 (IC50s = 0.288, 1.62, and 12.3 nM, respectively). [1] Galanin binds to and inhibits contraction of guinea pig gastric smooth muscle cells induced by carbachol . [2] In vivo, Galanin (6 nmol, i.c.v.) increases feeding behavior in rats and increases latency to hindpaw withdrawal in response to heat and mechanical stimulation in a rat model of carrageenin-induced inflammation when administered at a dose of 2 nmol injected into the nucleus accumbens.[3][4] Galanin (5 μg, i.c.v.) also inhibits acetylcholine release induced by scopolamine in the ventral hippocampus of freely moving rats. [5]

Proadrenomedullin N-terminal 12 peptide (PAMP-12), an endogenous fragment originating from the adrenal medulla and spanning amino acids 9-20 of human PAMP-20, plays a role in causing hypotension. It functions as an agonist for the MAS-related G protein-coupled receptor family member X2 (MRGPRX2), inhibiting forskolin-stimulated cAMP accumulation in CHO cells expressing human MRGPRX2 (EC50 = 57.2 nM) and selectively prompting calcium mobilization in these cells (EC50 = 41 nM), but not in cells expressing MRGPRX1, MRGPRX3, or MRGPRX4 at 1 µM. As an antagonist of nicotinic acetylcholine receptors (nAChRs), PAMP-12 obstructs carbachol-triggered catecholamine release and the influx of calcium and sodium (IC50s = 1.3, 0.39, and 0.87 µM, respectively) in primary bovine adrenal chromaffin cells, with no effect on histamine-induced responses (IC50s = >1 µM for all). Additionally, it decreases mean arterial blood pressure in normotensive rats at doses ranging from 10 to 50 nmol/kg.