Fig. 2.
Twenty-four-hour pretreatment with isoproterenol does not induce desensitization of PGE2 cAMP responses. HFL-1 cells were treated with 100 nM isoproterenol for 24 h then washed, and acute responses to PGE2 (a) or isoproterenol (b) were measured. cAMP levels were measured as a function of change in fluorescence normalized to the change in fluorescence of maximal response stimulated by 1 μM forskolin plus 200 μM IBMX using the cADDis assay. Data are mean ± SEM of n = 5. a Not significant (p = 0.612) and b significant (p = 0.0318) by 2-way ANOVA