Hernandez-Vivanco_2014_PLoS.One_9_e94142

Nicotinic acetylcholine receptors (nAChRs) that contain alpha6 and beta4 subunits have been demonstrated functionally in human adrenal chromaffin cells, rat dorsal root ganglion neurons, and on noradrenergic terminals in the hippocampus of adolescent mice. In human adrenal chromaffin cells, alpha6beta4* nAChRs (the asterisk denotes the possible presence of additional subunits) are the predominant subtype whereas in rodents, the predominant nAChR is the alpha3beta4* subtype. Here we present molecular and pharmacological evidence that chromaffin cells from monkey (Macaca mulatta) also express alpha6beta4* receptors. PCR was used to show the presence of transcripts for alpha6 and beta4 subunits and pharmacological characterization was performed using patch-clamp electrophysiology in combination with alpha-conotoxins that target the alpha6beta4* subtype. Acetylcholine-evoked currents were sensitive to inhibition by BuIA[T5A,P6O] and MII[H9A,L15A]; alpha-conotoxins that inhibit alpha6-containing nAChRs. Two additional agonists were used to probe for the expression of alpha7 and beta2-containing nAChRs. Cells with currents evoked by acetylcholine were relatively unresponsive to the alpha7-selctive agonist choline but responded to the agonist 5-I-A-85380. These studies provide further insights into the properties of natively expressed alpha6beta4* nAChRs.