Searching across hundreds of databases

Our searching services are busy right now. Your search will reload in five seconds.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

Morphological and functional changes in TRPM8-expressing corneal cold thermoreceptor neurons during aging and their impact on tearing in mice.

The Journal of comparative neurology | 2018

Morphological and functional alterations of peripheral somatosensory neurons during the aging process lead to a decline of somatosensory perception. Here, we analyze the changes occurring with aging in trigeminal ganglion (TG), TRPM8-expressing cold thermoreceptor neurons innervating the mouse cornea, which participate in the regulation of basal tearing and blinking and have been implicated in the pathogenesis of dry eye disease (DED). TG cell bodies and axonal branches were examined in a mouse line (TRPM8BAC -EYFP) expressing a fluorescent reporter. In 3 months old animals, about 50% of TG cold thermoreceptor neurons were intensely fluorescent, likely providing strongly fluorescent axons and complex corneal nerve terminals with ongoing activity at 34°C and low-threshold, robust responses to cooling. The remaining TRPM8+ corneal axons were weakly fluorescent with nonbeaded axons, sparsely ramified nerve terminals, and exhibited a low-firing rate at 34°C, responding moderately to cooling pulses as do weakly fluorescent TG neurons. In aged (24 months) mice, the number of weakly fluorescent TG neurons was strikingly high while the morphology of TRPM8+ corneal axons changed drastically; 89% were weakly fluorescent, unbranched, and often ending in the basal epithelium. Functionally, 72.5% of aged cold terminals responded as those of young animals, but 27.5% exhibited very low-background activity and abnormal responsiveness to cooling pulses. These morpho-functional changes develop in parallel with an enhancement of tear's basal flow and osmolarity, suggesting that the aberrant sensory inflow to the brain from impaired peripheral cold thermoreceptors contributes to age-induced abnormal tearing and to the high incidence of DED in elderly people.

Pubmed ID: 29664111 RIS Download

Research resources used in this publication

Additional research tools detected in this publication

None found

Associated grants

None

Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.

This is a list of tools and resources that we have found mentioned in this publication.


CGRP antibody (antibody)

RRID:AB_725807

This polyclonal targets CGRP

View all literature mentions

Anti-GFP antibody (antibody)

RRID:AB_300798

This polyclonal targets GFP

View all literature mentions

Alexa Fluor 594 (antibody)

RRID:AB_2313921

This unknown targets

View all literature mentions

Anti-TrkA (antibody)

RRID:AB_310180

This polyclonal targets TrkA

View all literature mentions

Anti-Peripherin (antibody)

RRID:AB_90725

This polyclonal targets Peripherin

View all literature mentions

Alexa Fluor 594 (antibody)

RRID:AB_2313921

This unknown targets

View all literature mentions

Anti-TrkA (antibody)

RRID:AB_310180

This polyclonal targets TrkA

View all literature mentions

Alexa Fluor 594 (antibody)

RRID:AB_2313921

This unknown targets

View all literature mentions

CGRP antibody (antibody)

RRID:AB_725807

This polyclonal targets CGRP

View all literature mentions

Anti-TrkA (antibody)

RRID:AB_310180

This polyclonal targets TrkA

View all literature mentions

Anti-GFP antibody (antibody)

RRID:AB_300798

This polyclonal targets GFP

View all literature mentions

Alexa Fluor 594 (antibody)

RRID:AB_2313921

This unknown targets

View all literature mentions

Anti-TrkA (antibody)

RRID:AB_310180

This polyclonal targets TrkA

View all literature mentions

Alexa Fluor 594 (antibody)

RRID:AB_2313921

This unknown targets

View all literature mentions

Anti-TrkA (antibody)

RRID:AB_310180

This polyclonal targets TrkA

View all literature mentions

Anti-GFP antibody (antibody)

RRID:AB_300798

This polyclonal targets GFP

View all literature mentions

CGRP antibody (antibody)

RRID:AB_725807

This polyclonal targets CGRP

View all literature mentions

Alexa Fluor 594 (antibody)

RRID:AB_2313921

This unknown targets

View all literature mentions

Anti-TrkA (antibody)

RRID:AB_310180

This polyclonal targets TrkA

View all literature mentions