Local pharmacological blockage of TRPV1 with the specific antagonist AMG9810, at a dosage that does not produce hyperthermia or affect thermal perception or locomotor activity, effectively attenuated thermal and mechanical hypersensitivity in bilateral hind paws of CPIP rats and reduced the hyperexcitability of DRG neurons induced by CPIP.
Conversely, genetic deletion of TRPV1 alleviated hyperthermia or LPS-induced abnormal microglial activation and restored a balanced inflammatory microenvironment in the brain.
The heat-sensitive transient receptor potential vanilloid-1 (TRPV1) receptors are localized in, and implicated in the heat sensitivity of peripheral and central structures involved in the respiratory response to hyperthermia.
Our results show that NIR pulses induce abrupt temperature elevation near the neuronal membrane and lead to both the TRPV1-channel and capacitive currents.
The results demonstrated that following the generation of fever using LPS, the expressions of TRPV1 and p‑TRPV1, and hypothalamic [Ca2+]i markedly increased.
We showed that, as expected, TRPV1 channels were activated by the heat produced by radiofrequency field exposure of transiently-transfected HEK293T cells, but found no evidence of TRPV1 activation in the absence of temperature elevation under radiofrequency field exposure.
TRPV1 KO mice have a normal basal body temperature, indicative of developmental compensation. d-Amphetamine (potent sympathomimetic) caused hyperthermia in WT mice, which was reduced in TRPV1 KO mice, suggesting a decreased sympathetic drive in KOs.
Transient receptor potential vanilloid subtype 1 (TRPV1) is a heat-sensitive ion channel that plays a key role in enhanced pain sensation after inflammation, but directly blocking TRPV1 causes hyperthermia and decreased sensitivity to painful levels of heat in animals and humans.
Thermoregulatory behaviour in relation to environmental thermopreference (30 vs. 35°C) was slightly impaired in male knockdown mice, but the reduction of TRPV1 function was not associated with enhanced hyperthermia.
Testicular hyperthermia in mice lacking transient receptor potential vanilloid receptor-1 results in a much more rapid and massive germ cell depletion from the seminiferous tubules than in wild-type animals, indicating that this receptor protects germ cells against heat stress.
However, several other TRPV1 antagonists are currently being evaluated in the clinic and soon-to-be-published results should shed light on the potential of managing antagonist-induced hyperthermia while developing them as therapeutics.