Fig. 5. Effects of nonhalogenated alkanes on recombinant receptors, including α4β2nicotinic acetylcholine (nACh), 5-hydroxytryptamine3A(5-HT3A), NR1/NR2A N -methyl-d-aspartate (NMDA), GluR1/GluR2 α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA), muscarinic1(M1) receptors, and G-protein–coupled inwardly rectifying potassium (GIRK1/2) channels. Cyclopropane (A ) at 1, 2, and 5 minimum alveolar concentration (MAC) and butane (B ) at 1 MAC were tested on the oocytes expressing receptors. Equipotent concentration (1 MAC) of cyclopropane and butane provided similar effects on all receptors with an exception of the AMPA receptors. Error bars represent SEM; n = 5–9 oocytes.