Fig. 5.
Dibutyryl-cAMP (dBcAMP) slows the degradation rate of the slow component, Rs, when measured by125I-BTX release (A) and of the material immunoprecipitated by the anti-ε subunit mAb 168 (B). Incubation in dB-cAMP increases thet½ of Rs (from 3.2 to 5.8 d) and that of the ε-subunit (from 2.7 to 4.3 d) but does not affect the t½ of Rr, which remains at 1.1 d (A). Dashed lines inA give the two component exponential decays for Rs and Rr (see Materials and Methods), which when summed give the best fit to the experimental data (solid lines) for each condition. The two exponentials for Rr overlap for control and dB-cAMP-treated cells.