TRPV4 activates autonomic and behavioural warmth-defence responses in Wistar rats

Author(s)

Vizin, R. C. L. ^[1] ; Scarpellini, C. da S. ^{[2, 3, 4]} ; Ishikawa, D. T. ^[1] ; Correa, G. M. ^{[2, 3]} ; de Souza, C. O. ^[1] ; Gargaglioni, L. H. ^{[2, 3]} ; Carrettiero, D. C. ^{[1, 5]} ; Bicego, K. C. ^{[2, 3]} ; Almeida, M. C. ^{[1, 5]}

Affiliation

^[1] Univ Fed ABC UFABC, Grad Program Neurosci & Cognit, BR-09606070 Sao Bernardo Do Campo, SP - Brazil

^[2] Natl Inst Sci & Technol Comparat Physiol INCT Fis, Jaboticabal, SP - Brazil

^[3] Sao Paulo State Univ, Dept Anim Morphol & Physiol, Coll Agr & Vet Sci, BR-14884900 Jaboticabal, SP - Brazil

^[4] Joint UFSCar UNESP Grad Program Physiol Sci, Sao Carlos, SP - Brazil

^[5] Univ Fed ABC UFABC, Nat & Humanities Sci Ctr, BR-09606070 Sao Bernardo Do Campo, SP - Brazil

• Document type: Journal article
• Source: ACTA PHYSIOLOGICA; v. 214, n. 2, p. 275-289, JUN 2015.
• Web of Science Citations: 18

Abstract

AimIn this study, we aimed at investigating the involvement of the warmth-sensitive channel - TRPV4 (in vitro sensitive to temperatures in the range of approx. 24-34 degrees C) - on the thermoregulatory mechanisms in rats. MethodsWe treated rats with a chemical selective agonist (RN-1747) and two antagonists (RN-1734 and HC-067047) of the TRPV4 channel and measured core body temperature, metabolism, heat loss index and preferred ambient temperature. ResultsOur data revealed that chemical activation of TRPV4 channels by topical application of RN-1747 on the skin leads to hypothermia and this effect was blocked by the pre-treatment with the selective antagonist of this channel. Intracerebroventricular treatment with RN-1747 did not cause hypothermia, indicating that the observed response was indeed due to activation of TRPV4 channels in the periphery. Intravenous blockade of this channel with HC-067047 caused an increase in core body temperature at ambient temperature of 26 and 30 degrees C, but not at 22 and 32 degrees C. At 26 degrees C, HC-067047-induced hyperthermia was accompanied by increase in oxygen consumption (an index of thermogenesis), while chemical stimulation of TRPV4 increased tail heat loss, indicating that these two autonomic thermoeffectors in the rat are modulated through TRPV4 channels. Furthermore, rats chemically stimulated with TRPV4 agonist choose colder ambient temperatures and cold-seeking behaviour after thermal stimulation (28-31 degrees C) was inhibited by TRPV4 antagonist. ConclusionOur results suggest, for the first time, that TRPV4 channel is involved in the recruitment of behavioural and autonomic warmth-defence responses to regulate core body temperature. (AU)

• FAPESP's process: 12/19966-0 - Cardiorespiratory pattern and awake-sleep state in male and female rats exposed to fluoxetine during prenatal period
• Grantee: Luciane Helena Gargaglioni Batalhão
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/19131-2 - Role of hypothalamic TRPV4 channels in activation/inhibition of autonomic thermoeffectors during fever and endotoxemic chock
• Grantee: Carolina da Silveira Scarpellini
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 09/11446-4 - The relationship between nicotinic receptor and degradation of toxic Tau molecule on Alzheimer's Disease: is the co-chaperone BAG2 involved?
• Grantee: Daniel Carneiro Carrettiero
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/11836-0 - Involvement of TRPV4 channels in thermoregulation and social behavior of Wistar rats
• Grantee: Robson Cristiano Lillo Vizin
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 11/06528-1 - Role of TRPV4 channels in thermoregulation
• Grantee: Maria Camila Almeida
• Support Opportunities: Regular Research Grants