Figure 7.

Cells expressing NPR-A-6E but not wild-type NPR-A demonstrate linear ANP-dependent cGMP accumulation. Human 293 cells were transiently transfected with either NPR-A (W.T.) or NPR-A-6E (6E) expression constructs and then split into 12-well plates 24 h later. The next day these cells were moved to ambient temperature and incubated with 0.5 ml of DMEM containing 0.5 mM 1-methyl-3-isobutylxanthine and 200 μM ANP for the periods shown. cGMP production was terminated by adding 0.5 ml of 6% trichloroacetic acid to each well at the indicated time and assayed as described in MATERIALS AND METHODS. The vertical bars contained within each symbol represent the SEM, where n = 4.