Figure 6.
Agonist potency and efficacy profiles for HEK α3 cell lines and IMR-32 cells. (A) Bar graph depicting the EC50 values from Fig. 4 for ACh, Nic, Cyt, and DMPP on the HEK transfected cell lines and IMR-32 cells. The potency profile for IMR-32 cells best matches the profiles for the α3β4 and the α3β4α5 cell lines. The biggest discrepancy was seen for the potency of Cyt, which was higher on the β4 containing transfected cell lines than on IMR-32 cells, but the potencies of the other three agonists matched well. (B) Bar graph depicting the efficacies of the four agonists on the HEK transfected cell lines and IMR-32 cells. The efficacies of Cyt and DMPP serve as good predictors of the β subunit identity in unknown AChRs. Thus, for IMR-32 AChRs, the efficacy of both Cyt and DMPP along with the agonist potency profiles lead us to conclude that the predominant AChR in these cells is α3β4.