Abstract

The rat corneal neurons expressing vanilloid receptor TRPV1, substance P (SP) and calcitonin-gene-related peptide (CGRP) were examined. In the cornea, some TRPV1-immunoreactive nerve fibers displayed either SP- or CGRP immunoreactivity also. For observing corneal neuronal elements in the trigeminal ganglion (TG) and in the medulla oblongata, retrograde and anterograde cholera toxin subunit B (CTB) tracing methods combining with triple immunofluorescence technique were performed. The corneal neuronal somata were located in the ophthalmic division of the TG; 37% of them were immunoreactive for TRPV1. One third and three quarters of the corneal TRPV1-immunoreactive neurons co-expressed SP and CGRP, respectively. All of SP-immunoreactive corneal neurons exhibited TRPV1 immunoreactivity. They were predominantly medium-sized (mean ± SE = 638.2 ± 49.5 μm 2) and significantly larger than SP-immunoreactive and TRPV1-immunonegative neurons in the ophthalmic division of the TG. The central projection fibers of corneal neurons co-expressing TRPV1 with SP and CGRP were observed at the subnucleus interpolaris/caudalis transition within trigeminal nucleus. The present study suggests that TRPV1 of the corneal neurons works in close relation to SP and CGRP both in the cornea and CNS for healing and nociceptive transduction.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.