New insight into the tick neuronal nicotinic acetylcholine receptors: from molecular to pharmacological studies

ACh is known to be an excitatory neurotransmitter in the central nervous system of several arthropod species. Nicotinic acetylcholine receptors are involved in rapid neurotransmission and are the target of compounds used as acaricides. In the present review, we discuss recent data on the study of the functional properties of tick neuronal nicotinic acetylcholine receptor subtypes present in the synganglion. Several nicotinic acetylcholine receptor subunits have been characterized in tick species. We show that despite difficulties expressing functional receptors in heterologous systems, recent advances using the microtransplantation of tick synganglion membranes in Xenopus oocytes, and electrophysiological recordings of native neurons help to understand the pharmacological properties of tick nicotinic receptors. In addition, molecular modeling studies provide new criteria in the study of ligand-receptor interactions.