TABLE 1
Agonist activity (EC50 and efficacy relative to SRIF-14) was assessed as the ability of the compounds to stimulate [35S]GTPγS binding in membranes of CHO cells expressing the human sst4 (CHO-h sst4)
Under routine testing conditions (100 mM NaCl and 10 μM GDP), SRIF-14 concentration dependently increased [35S]GTPγS binding to give fitted curve maxima of ∼110% over basal, whereas the corresponding value under lower NaCl and GDP conditions (20 mM NaCl and 3 μM GDP) was ∼45% over basal. Data represent means ± S.E.M. from at least three experiments. Representative curves for J-2156, compound A, SRIF-14, and CST-17 are shown in Fig. 1. Agonist activities of J-2156, SRIF-14, and LTT-SRIF-28 as determined in the presence of 100 mM NaCl and 10 μM GDP have been reported by us earlier (Engström et al., 2005).