Nav1.7 is required for normal C-low threshold mechanoreceptor function in humans and mice.
Brain
; 145(10): 3637-3653, 2022 10 21.
Article
em En
| MEDLINE
| ID: mdl-34957475
ABSTRACT
Patients with bi-allelic loss of function mutations in the voltage-gated sodium channel Nav1.7 present with congenital insensitivity to pain (CIP), whilst low threshold mechanosensation is reportedly normal. Using psychophysics (n = 6 CIP participants and n = 86 healthy controls) and facial electromyography (n = 3 CIP participants and n = 8 healthy controls), we found that these patients also have abnormalities in the encoding of affective touch, which is mediated by the specialized afferents C-low threshold mechanoreceptors (C-LTMRs). In the mouse, we found that C-LTMRs express high levels of Nav1.7. Genetic loss or selective pharmacological inhibition of Nav1.7 in C-LTMRs resulted in a significant reduction in the total sodium current density, an increased mechanical threshold and reduced sensitivity to non-noxious cooling. The behavioural consequence of loss of Nav1.7 in C-LTMRs in mice was an elevation in the von Frey mechanical threshold and less sensitivity to cooling on a thermal gradient. Nav1.7 is therefore not only essential for normal pain perception but also for normal C-LTMR function, cool sensitivity and affective touch.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Insensibilidade Congênita à Dor
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Canal de Sódio Disparado por Voltagem NAV1.7
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article