TABLE 4

Potency (EC50) and relative efficacy (Emax) values for SNF and RNF at wild-type and point mutant 5-HT2 receptors

Emax is reported as % maximum response to 5-HT. p values were obtained from F-tests comparing curve fits of concentration-response isotherms for two receptors. Where applicable, values are presented as mean ± S.E.

Receptor pEC50 (EC50) Emax
SNF RNF SNF RNF
nM % 5-HT max
5-HT2B WT 7.66 ± 0.07 (22) 6.62 ± 0.07 (240) 75 ± 3 81 ± 4
A1.35P 7.7 ± 0.1 (20) N.D. N.D. N.D.
A1.35S 7.69 ± 0.06 (20) N.D. N.D. N.D.
L1.38S 7.51 ± 0.08 (30) N.D. N.D. N.D.
I1.39T 7.50 ± 0.09 (31) N.D. N.D. N.D.
V1.42I 7.44 ± 0.08 (36) N.D. N.D.
V2.53L 7.09 ± 0.07a (82) 6.99 ± 0.07a (100) 101.7 ± 0.6a 28.2 ± 0.5a
V2.53I 7.7 ± 0.1 (20) 7.4 ± 0.1a (40) 87 ± 4a 73 ± 4
L3.29I 7.92 ± 0.03a (12) N.D. N.D. N.D.
M5.39V 7.19 ± 0.09a (64) 6.7 ± 0.1 (200) 70 ± 3 74 ± 5
V2.53L, M5.39V 6.49 ± 0.05abc (320) 6.80 ± 0.08b (160) 73 ± 4b 18 ± 1abc
E7.36N 7.6 ± 0.1 (20) N.D. N.D. N.D.
S7.45C 7.8 ± 0.2 (10) N.D. N.D. N.D.
5-HT2A WT 6.7 ± 0.2 (200) 6.6 ± 0.2 (300) 75 ± 3 69 ± 5
5 HT2A L2.53V 5.3 ± 0.1a (5000) 5.07 ± 0.09a (8500) 70 ± 3 68 ± 5
5-HT2C WT 7.2 ± 0.2 (70) 6.7 ± 0.1 (200) 93 ± 6 89 ± 6
5-HT2C V2.53L 7.2 ± 0.1 (70) 6.97 ± 0.8a (100) 85 ± 5 82 ± 4
  • N.D., not determined.

  • a P < 0.05 compared with the appropriate WT 5-HT2 receptor.

  • b P < 0.05 compared with the V2.53L 5-HT2B receptor.

  • c P < 0.05 compared with the M5.39V 5-HT2B receptor.