Neuronal messengers and peptide receptors in the human sphenopalatine and otic ganglia

Abstract

A majority of the parasympathetic nerve fibers to cranial structures derive from the sphenopalatine and otic ganglia. In particular, blood vessels are invested with a rich supply of dilator fibers of parasympathetic origin. In the present study, we have examined the occurrence of noncholinergic neuromessengers and neuropeptide receptors in the human sphenopalatine and otic ganglia. Vasoactive intestinal peptide (VIP)-immunoreactive (ir) nerve cell bodies occurred in high numbers in the sphenopalatine and otic ganglia. Likewise, high numbers of NOS- and PACAP-containing nerve cell bodies were seen in both ganglia. Autofluorescent lipofuscin, characteristic of adult human nervous tissue, was present within many nerve cell bodies in both ganglia. Receptor mRNA was studied with reverse transcriptase–polymerase chain reaction (RT-PCR). Total RNA from the sphenopalatine and otic ganglia was successfully extracted. By using appropriate sense and antisense primers, oligonucleotides were designed from the human sequences derived from GenBank, corresponding to human NPY Y 1, CGRP 1 and VIP 1 receptors. In the sphenopalatine ganglion, we revealed the presence of mRNA for the human NPY Y 1 and VIP 1 receptors but not the CGRP 1 receptor. The otic ganglion was found to react positively only for primers to mRNA for VIP 1 but not for CGRP 1 or NPY Y 1 receptors.