Add like
Add dislike
Add to saved papers

Dry eye sensitizes cool cells to capsaicin-induced changes in activity via TRPV1.

Corneal cool cells are sensitive to the ocular fluid status of the corneal surface and may be responsible for the regulation of basal tear production. Previously, we have shown that dry eye, induced by lacrimal gland excision (LGE) in rats, sensitized corneal cool cells to the TRPM8 agonist menthol and to cool stimulation. In the present study, we examined the effect of dry eye on the sensitivity of cool cells to the TRPV1 agonist capsaicin. Single-unit recordings in the trigeminal ganglion were performed 7-10 days after LGE. At a concentration of 0.3mM, capsaicin did not affect ongoing or cool-evoked activity in control animals yet facilitated ongoing activity and suppressed cool-evoked activity in LGE animals. At higher concentrations (3 mM), capsaicin continued to facilitate ongoing activity in LGE animals but suppressed ongoing activity in control animals. Higher concentrations of capsaicin also suppressed cool-evoked activity in both groups of animals, with an overall greater effect in LGE animals. In addition to altering cool-evoked activity, capsaicin enhanced the sensitivity of cool cells to heat in LGE animals. Capsaicin-induced changes were prevented by the application of the TRPV1 antagonist capsazepine. Using fluorescent in situ hybridization, TRPV1 and TRPM8 expression was examined in retrograde tracer identified corneal neurons. The co-expression of TRPV1 and TRPM8 in corneal neurons was significantly greater in LGE treated animals when compared to sham controls. These results indicate that LGE-induced dry eye increases TRPV1-mediated responses in corneal cool cells at least in part through the increased expression of TRPV1.

Full text links

We have located links that may give you full text access.
Can't access the paper?
Try logging in through your university/institutional subscription. For a smoother one-click institutional access experience, please use our mobile app.

For the best experience, use the Read mobile app

Mobile app image

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app

All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

By using this service, you agree to our terms of use and privacy policy.

Your Privacy Choices Toggle icon

You can now claim free CME credits for this literature searchClaim now

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app