OCULAR SURFACE WETNESS IS REGULATED BY TRPM8-DEPENDENT COLD THERMORECEPTORS OF THE CORNEAL

AUTHORS:

Andrés Parra, Rodolfo Madrid, Diego Echevarria, Susana del Olmo, Cruz Morenilla-Palao, M Carmen Acosta, Juana Gallar, Ajay Dhaka, Félix Viana & Carlos Belmonte.

ABSTRACT.

Basal tearing is crucial to maintaining ocular surface wetness. Corneal cold thermoreceptors sense small oscillations in ambient temperature and change their discharge accordingly. Deletion of the cold-transducing ion channel Transient receptor potential cation channel subfamily M member 8 (TRPM8) in mice abrogates cold responsiveness and reduces basal tearing without affecting nociceptor-mediated irritative tearing. Warming of the cornea in humans also decreases tearing rate. These findings indicate that TRPM8-dependent impulse activity in corneal cold receptors contributes to regulating basal tear flow.

Nature Medicine 16, 1396-1399 (2010) doi: 10.1038/nm.2264 Andrés Parra, Rodolfo Madrid, Diego Echevarría, Susana del Olmo, Cruz Morenilla-Palao, M. Carmen Acosta, Juana Gallar, Ajay Dhakad, Félix Viana & Calos Belmonte. Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, San Juan de Alicante, Spain. Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile. Fundación de Investigación Oftalmológica, Instituto de Oftalmología Fernández-Vega, Oviedo, Spain. Department of Biological Structure, University of Washington, Seatle, Washington, USA.