Hypothalamic TRPV4 channels participate in the medial preoptic activation of warmth-defence responses in Wistar male rats

Autor: Caroline Cristina-Silva, Carolina da Silveira Scarpellini, Kênia C. Bícego, Maria Camila Almeida, Luciane H. Gargaglioni, Vivian Biancardi
Přispěvatelé: Universidade Estadual Paulista (Unesp), St. Michael’s Hospital, University of Alberta, Universidade Federal do ABC (UFABC)
Rok vydání: 2019
Předmět:
Zdroj: Scopus
Repositório Institucional da UNESP
Universidade Estadual Paulista (UNESP)
instacron:UNESP
ISSN: 1432-2013
0031-6768
DOI: 10.1007/s00424-019-02303-1
Popis: Made available in DSpace on 2019-10-06T17:18:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Recently, we have described, in non-genetically modified rats, that peripheral transient receptor potential vanilloid-4 (TRPV4) channels are activated and trigger warmth-defence responses at ambient temperatures of 26–30 °C. Evidence points to the presence of TRPV4 in the medial preoptic area, a region described to be involved in the activation of thermoeffector pathways, including those involved in heat loss. Thus, we tested the hypothesis that TRPV4 in the medial preoptic area modulates thermoregulation under warm conditions. To this end, under two ambient temperatures (21 and 28 °C), body temperature was measured in rats following blockade of preoptic TRPV4 with two antagonists, HC-067047 and GSK 2193874. Oxygen consumption, heat loss index and preferred ambient temperature were also determined in order to assess thermoeffector activity. Antagonism of central TRPV4 caused an increase in body temperature in rats exposed to 28 °C, but not in those exposed to 21 °C. The body temperature increase at 28 °C was accompanied by an increase in oxygen consumption and an earlier reduction of the heat loss index. In behavioural experiments, control animals previously exposed to warm ambient temperatures (28–30 °C) for 2 h selected colder temperatures in a thermogradient compared to those injected with HC-067047. Our results support the idea that preoptic TRPV4 modulates thermoregulation in a warm environment by activating both autonomic and behavioural heat loss responses. Thus, according to the present study and to that published recently by our group, the activation of warmth-defence responses by TRPV4 seems to be dependent on the activity of both peripheral and central channels. Department of Animal Morphology and Physiology College of Agricultural and Veterinary Sciences Sao Paulo State University, Via de Acesso Prof. Paulo D. Castellane, s/n; Bairro Rural Joint UFSCar-UNESP Graduate Program of Physiological Sciences Keenan Research Centre for Biomedical Science St. Michael’s Hospital Department of Physiology Faculty of Medicine and Dentistry University of Alberta Center for Natural and Human Sciences Universidade Federal do ABC (UFABC) Department of Animal Morphology and Physiology College of Agricultural and Veterinary Sciences Sao Paulo State University, Via de Acesso Prof. Paulo D. Castellane, s/n; Bairro Rural Joint UFSCar-UNESP Graduate Program of Physiological Sciences FAPESP: 15/02991-0 FAPESP: 15/04849-6 FAPESP: 2011/19131-2 FAPESP: 2012/15298-2 FAPESP: 2017/17278-2 CNPq: 442560/2014-1
Databáze: OpenAIRE
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