Objectives: Endothelin is a potent peptide mediator that is synthesized by a number of cells. Previous studies have revealed the occurrence of endothelin in nerve cell bodies of some peripheral ganglia. Endothelin mediates its effects via two distinct receptor subtypes ETA and ETB. The present study was designed to investigate the presence of these two receptors in the human trigeminal ganglion.
Methods: Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to show the presence of mRNA encoding ETA and ETB receptors in the human trigeminal ganglion. To localize the protein immunocytochemistry with antibodies against the endothelin receptors was used.
Results: Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis revealed mRNA for both receptor subtypes in the human trigeminal ganglion. Immunocytochemistry revealed numerous cell bodies containing the ETA and the ETB receptor proteins.
Conclusions: The expression of ETA and ETB receptors in the human trigeminal ganglion suggests a role for endothelin in autonomic and sensory neural transmission.