TABLE 3

SPAP gene transcription responses to β2-agonists, partial agonists, and β -blockers after preincubation with inhibitors (50 μM U0126, 50 μM PD 98059, or 10 μM RO 318220)

The percentage of maximum isoprenaline response is expressed as a percentage of the response to 10 μM isoprenaline measured in the same experiment. The remaining columns indicate the percentage of that ligand's maximum response (in the absence of inhibitor).

Agonist Percentage of Maximum Isoprenaline Response n Agonist + U0126 n Agonist + PD 98059 n Agonist + RO 318220 n
% % %
Isoprenaline 100 46 13.0 ± 1.8 6 65.1 ± 2.7 12 31.4 ± 4.5 10
Forskolin 91.3 ± 2.9 7 6.6 ± 1.0 3 N.D. 9.2 ± 4.7 3
Salbutamol 95.1 ± 2.4 20 10.9 ± 2.2 5 64.8 ± 2.8 6 23.3 ± 3.5 3
Salmeterol 102.2 ± 4.9 5 10.1 ± 0.7 3 69.5 ± 1.5 4 28.0 ± 6.2 3
CGP 12177 63.4 ± 1.9 12 3.6 ± 2.1 3 85.5 ± 2.6 6 28.0 ± 8.2 3
Alprenolol 48.5 ± 1.4 28 18.1 ± 4.7a 5 N.D. 33.0 ± 1.9 3
(±)-Propranolol 14.2 ± 0.9 25 19.3 ± 9.9a 5 N.D. 34.3 ± 15.6 5
  • N.D., not determined.

  • a 30 μM U0126.