Table 3

Effects of dibutyryl cAMP, forskolin, staurosporine, and H-8 on BP transport in rat small intestine

AdditionBP Transport
nmol/g wet wt./30 min
None46.7  ± 5.1
Epinephrine (100 μM)233.6  ± 6.5***
Dibutyryl cAMP (10 μM)101.5  ± 7.83-150
Dibutyryl cAMP (10 μM) + phenylephrine (100 μM)206.4  ± 4.0***
Dibutyryl cAMP (10 μM) + clonidine (100 μM)260.3  ± 8.7***
Forskolin (2.5 μM)176.7  ± 14.3**
Forskolin (2.5 μM) + phenylephrine (100 μM)287.9  ± 20.9***
Staurosporine (1 μM)40.4  ± 1.2
Staurosporine (1 μM) + epinephrine (100 μM)84.2  ± 5.4
H-8 (60 μM)50.4  ± 2.2
H-8 (60 μM) + epinephrine (100 μM)93.3  ± 6.83-150

After equilibration with Ringer's solution containing 1 mM BP and a trace amount of [3H]BP, rat small intestinal lumen was perfused for 30 min with the same solution containing the indicated agents. For the staurosporine and H-8 experiments, loops were pretreated with these inhibitors for 15 min before the addition of epinephrine to the luminal perfusate. The amount of BP in the serosal solution was then determined as described in the text. Data are mean ± S.E. for four loops.

  • 3-150P < .05, **P < .01, and ***P < .001 versus control (none).