FIGURE 2.

Non-hydrolyzable AMP analog activates hA₁R but not hA_2BR. A and B, structures of AMP (A) and the non-hydrolyzable analog ACP (B) at physiological pH. C, calcium mobilization responses elicited by 1 mm ACP in HEK293 cells expressing (solid line) hA₁R + Gqi or (dashed line) hA_2BR + Gqs. Cells expressing Gqi alone did not respond to ACP. AUC measurements extended for 1 min from agonist addition. Paired t tests were used to compare AUC data, ***, p < 0.0005. Data are the average of one (hA_2BR) or two (hA₁R) experiments performed in duplicate. n = 28–73 cells per condition. All data, including calcium traces, are presented as means ± S.E.