Table 4.

Residues involved in the docking of S-(+)-citalopram (escitalopram) to luminal sites at the h(α3)₃(β4)₂ AChR.

Luminal Site	TBE (Kcal/mol)	RMSD Mean / Var	α3	β4	Homologous residues a		M2 Position (nng)
					α9	α10
High-affinity	−14.31	2.30 / 0.02	I246*		V248	V248	5′
				S248*	T249	T249	6′ (Ser)
			L249		L251	L251	8′
			L250	L251	L252	L252	9′ (Leu)
			S251	A252	A253	A253	10′
			T253	T254 (H-bond donor)	T255	T255	12′
			V254	F255	V256	V256	13′ (Val)
			F255(Cation-π)	F256	F257	F257	14′
				L258	L259	L259	16′
Low-affinity	−4.27	2.55 / 0.07	G239	G240	G241	G241	−3′ (Gly)
			E240	E241	E242	E242	−2′
			V242	M243	V244	V244	1′
			T243	T244	S245	S245	2′ (Thr)
				L245	L246	L246	3′
			1246*	1247	V248	V248	5′
			S247	S248*	T249	T249	6′ (Ser)

^*Residues from the high- and low-affinity sites belong to different α3 and β4 indicating no overlapping between both sites.

^aThe homologous residues at α9 and α10 subunits are also included for comparative purposes.