FIGURE 7.

p10 activates GPHRs in tissues. A and B, cell suspensions from mouse thyroid (A) and mouse testis (B) were incubated with TSH and hCG, respectively, and with p10, p10 E5K, and a control peptide (scrambled amino acids of p10). Basal cAMP levels for thyroid and testis were 5.8 ± 2.3 and 30.1 ± 10.5 nm/well, respectively. C, cell suspension from testis was incubated with the indicated compounds, and testosterone levels were determined with an ELISA (see “Experimental Procedures”). Data are means ± S.E. of three (A and C) and five (B) independent experiments performed in triplicate. *, p < 0.05, **, p < 0.01, ***, p < 0.001 (paired Student's t test).