Table 1.

Electrophysiological data for WT and mutant 5-HT₃ receptors

M2 4′ amino acid	Imax (pA)	EC50 (μm)	nH	Vrev (mV)
K (WT)	656 ± 170	2.34 ± 0.06	2.87 ± 0.35	−9.0 ± 1.6
R	469 ± 89	1.50 ± 0.08*	2.97 ± 0.18	−6.8 ± 0.4
Q	775 ± 117	1.47 ± 0.06*	2.77 ± 0.47	−10.6 ± 0.9
S	979 ± 364	1.54 ± 0.04*	2.39 ± 0.34	−8.6 ± 2.3
G	545 ± 271	1.39 ± 0.10*	2.73 ± 0.27	−8.2 ± 1.9

Data are means ± s.e.m. (n = 4).

^*Significantly different from WT (Student's t test, P < 0.05). Amino acids: K, lysine; R, arginine; Q, glutamine; S, serine; G, glycine.