Characteristics of scratching behavior in ADJM mice (atopic dermatitis from Japanese mice)

Abstract

In order to elucidate the characteristics of scratching behavior in atopic dermatitis from Japanese mice (ADJM) mice, the effects of some antagonists of pruritogens on this behavior were studied. Both male and female ADJM mice showed frequent scratching behavior around the face, abdomen and back. The number of scratching behavior around the face was greater than on the abdomen and back, and scratching behavior in female mice was significantly more frequent than in male mice. Histamine H₁ antagonist, chlorpheniramine, p.o., inhibited this behavior potently and dose-dependently. Histamine H₁ antagonist with serotonin 5-TH(5-hydroxytryptamine)₂ antagonist, cyproheptadine, also inhibited this behavior. However, NK₁ antagonist, aprepitant, p.o., had no significant inhibitory effect even at a dose of 100 mg/kg, p.o., Mu antagonist, naloxone, and kappa agonist, nalfurafine, significantly inhibited this behavior at doses of 0.3 mg/kg, s.c., and 0.01 mg/kg, p.o., respectively. Histamine contents in the skin of ADJM mice were significantly higher than in BALB/c mice. These results strongly indicate that scratching behavior in ADJM mice is related with histamine H₁, opioid mu and opioid kappa receptors.

• ADJM mice
• chlorpheniramine
• cyproheptadine
• nalfurafine
• naloxone

Declaration of interest

The authors report no conflict of interest. The authors alone are responsible for the content and writing of the article.

This work was supported by Kawano Masanori Memorial Public Interest Incorporated Foundation for Promotion of Pediatrics and JSPS KAKENHI Grant Number 70458610.