Activation of orexinergic and histaminergic pathway involved in therapeutic effect of histamine H receptor antagonist against cisplatin-induced anorexia in mice.

We previously reported that hypothalamic tumor necrosis factor-alpha (TNF-α) mRNA expression via histamine H receptors contributes to the development of cisplatin-induced anorexia; however, its precise mechanisms remain unclear. It has been reported that chemotherapeutic agents induce the suppression of orexin neuron activity, and the administration of orexin inhibits chemotherapeutic agent-induced gastric discomfort. Other studies demonstrated that the central administration of TNF-α impairs the orexinergic system, and that orexin excites the histaminergic system.

Involvement of leukotriene pathway in the development of sevoflurane-induced pica in rats.

We previously reported that sevoflurane-induced pica, kaolin ingestion behavior, in rats has the potential to reflect postoperative nausea and vomiting (PONV) in humans. It is well-known that corticosteroids, which inhibit both prostaglandin and leukotriene syntheses due to phospholipase A inhibition, are effective for reducing PONV; however, the precise mechanisms remain unclear. We investigated the involvement of the prostaglandin or leukotriene pathway in the development of sevoflurane-induced pica.

Involvement of the Hypothalamic Glutamatergic System in the Development of Radiation-Induced Pica in Rats.

Since the peripheral serotoninergic pathway is involved in the development of radiation-induced nausea and vomiting, referred to as radiation sickness, serotonin 5-HT receptor antagonists are used as a preventive measure, although patients still suffer from these symptoms. Glutamate is known as the excitatory neurotransmitter and is involved in various autonomic symptoms. We investigated the effect of radiation on glutamate release in rats, as measured by in vivo brain microdialysis, and the effects of glutamate receptor antagonists on radiation-induced pica, which can be used as a behavioral assessment of radiation sickness in rats.

Effects of a histamine H receptor antagonist on cisplatin-induced anorexia in mice.

Cancer chemotherapy often induces gastrointestinal symptoms such as anorexia, nausea, and vomiting. Antiemetic agents are effective in inhibiting nausea and vomiting, but patients still experience anorexia. We previously reported that chemotherapeutic agent-induced anorexia is associated with an increase of inflammatory cytokines.

Strain differences in the development of cisplatin-induced pica behavior in mice.

Introduction: Pica behavior, kaolin ingestion, in rats and mice can be used as an assessment of nausea and vomiting; however, we observed that the incidence of pica behavior in ICR strain mice varied markedly. We investigated the susceptibility of four strains of mice (ICR, BALB/c, C57BL/6, and DBA/2) to the development of pica behavior.

Methods: Mice received cisplatin (7.