Coupling of rat somatostatin receptor subtypes to a G-protein gated inwardly rectifying potassium channel (GIRK1)

The five different rat somatostatin receptor subtypes (SSTR1–SSTR5) were coexpressed with a subunit of G-protein gated inwardly rectifying potassium channel (GIRK1) in Xenopus oocytes. SSTR2–SSTR5, but not SSTR1 coupled efficiently to the activation of GIRK currents when stimulated by SST14 or SST28. A comparison of the dose-response curves and of the maximum currents obtained indicates that SSTR2 couples most efficiently to this effector, supporting the notion that SSTR2 is involved in activation of potassium conductances by SST in vivo.