Identification of hypothermia-inducing neurons in the preoptic area and activation of them by isoflurane anesthesia and central injection of adenosine.

Hibernation and torpor are not passive responses caused by external temperature drops and fasting but are active brain functions that lower body temperature. A population of neurons in the preoptic area was recently identified as such active torpor-regulating neurons. We hypothesized that the other hypothermia-inducing maneuvers would also activate these neurons.

Activation of the nucleus accumbens promotes place preference and counteracts stress-induced hyperthermia.

Positive affect promotes mental health and physical well-being, which may involve modifications in the autonomic nervous system activity. Here, we examine, using chemogenetic techniques, the effects of nucleus accumbens (NAc) activation on affect and body temperature regulation as a proxy of autonomic function. A conditioned place preference test revealed that nucleus accumbens activation induced positive affect.

TRPA1 contributes to respiratory depression from tobacco aerosol.

Transient receptor potential ankyrin-1 (TRPA1) is expressed in the trigeminal nerves in the nasal cavity. It detects irritant chemicals such as formalin and acrolein, induces respiratory depression to protect against further inhalation, and elicits avoidance behavior. Although tobacco smoke contains formalin, acrolein, and other irritant chemicals, the possible contribution of TRPA1 to protection against tobacco smoke has yet to be fully understood.

Identification of hypothermia-inducing neurons in the preoptic area and activation of them by isoflurane anesthesia and central injection of adenosine.

Hibernation and torpor are not passive responses caused by external temperature drops and fasting but are active brain functions that lower body temperature. A population of neurons in the preoptic area was recently identified as such active torpor-regulating neurons. We hypothesized that the other hypothermia-inducing maneuvers would also activate these neurons.

Orexin neurons play contrasting roles in itch and pain neural processing via projecting to the periaqueductal gray.

Pain and itch are recognized as antagonistically regulated sensations; pain suppresses itch, whilst pain inhibition enhances itch. The neural mechanisms at the central nervous system (CNS) underlying these pain-itch interactions still need to be explored. Here, we revealed the contrasting role of orexin-producing neurons (ORX neurons) in the lateral hypothalamus (LH), which suppresses pain while enhancing itch neural processing, by applying optogenetics to the acute pruritus and pain model.