IC90: 0.0037 nM for rat SSTR5, 3.6 nM for human SSTR5
Somatostatin receptor type 5 is a protein that in humans is encoded by the SSTR5 gene. Somatostatin acts at many sites to inhibit the release of many hormones and other secretory proteins. SSTR5 is a member of the superfamily of receptors having seven transmembrane segments. BIM 23052 is a linear somatostatin agonist, which displays high binding affinity for the cloned rat sst5 receptor
In vitro: BIM 23052 and the CGP 23996-like compounds bind selectively to rat SSTR5 versus human SSTR1, mouse SSTR2, mouse SSTR3, and human SSTR4.The linear compound BIM 23052 displayed approximately 1000-fold lower affinity for human SSTR5 than for rat SSTR5. Compounds that bind potently to human SSTR5, such as L-362, 855 and BIM 23052, are relatively less potent in GH inhibition [1].
In vivo: BIM 23052 (0.4, 0.8, and 1.2 nmol/rat i.c.) stimulated gastric transit; values of gastric emptying were 65.5 +/- 6.5, 77.4 +/- 5.3, and 77.7 +/- 1.9%, respectively, compared with 43.2 +/-3.2% in i.c. saline group. Intravenous injection of BIM 23052 (0.8 nmol/rat) had no effect. BIM 23052 (0.8 nmol/rat i.c.) action was prevented by subdiaphragmatic vagotomy or atropine [2].
Clinical trial: Up to now, BIM-23052 is still in the preclinical development stage.
References:
[1] O'Carroll AM, Raynor K, Lolait SJ, Reisine T. Characterization of cloned human somatostatin receptor SSTR5. Mol Pharmacol. 1994 Aug;46(2):291-8.
[2] Martínez V, Rivier J, Coy D, Taché Y. Intracisternal injection of somatostatin receptor 5-preferring agonists induces a vagal cholinergic stimulation of gastric emptying in rats. J Pharmacol Exp Ther. 2000 Jun;293(3):1099-105.