Figure 5.
Effect of TM peptides on SCTR cAMP signaling. Intracellular cAMP accumulation in response to graded concentrations of SCT in SCTR/AT1aR- or SCTR-transfected cells. A) Compared to no peptide treatment, ATM4 and STM-IV further reduced the efficacy of cAMP production through stimulation of the SCTR in SCTR/AT1aR-transfected cells. B) In contrast, there was no significant effect of ATM-1 or STM-II on cAMP production in SCTR/AT1aR-transfected cells. C) ANGII treatment was able to rescue the cAMP response to SCT in SCTR-AT1aR cells, but this effect was repressed by ATM1. D) In SCTR-transfected cells, ATM-4 and STM-IV significantly reduced receptor responses to SCT. ATM1 treatment did not alter the cAMP response of SCTR, whereas STM-II slightly reduced the Emax value. Data are presented as means ± se of data from ≥3 independent experiments performed in triplicate.