Spontaneous scratching behaviour in DS-Nh mice as a possible model for pruritus in atopic dermatitis

Immunology. 2006 Jul;118(3):293-301. doi: 10.1111/j.1365-2567.2006.02365.x.

Abstract

Itching is one of the major clinical symptoms in atopic dermatitis (AD) and complicates the management of this pathological condition. An animal model of AD-like pruritus would contribute to a better understanding of AD and could lead to the development of safe and effective antipruritic agents. DS non-hair (DS-Nh) mice raised under conventional conditions spontaneously develop pruritus, which is associated with a dermatitis similar to human AD. There is a significant positive correlation between disease severity and the period of scratching behaviour in DS-Nh mice. In the present study, we found that levels of histamine and nerve growth factor (NGF) in serum and/or skin tissue were higher in DS-Nh mice with AD-like dermatitis than in age-matched mice without dermatitis. The histopathological data indicated that nerve fibres extend into and mast cells infiltrate the surrounding area of the skin lesion. NGF production by XB-2 cells, which was derived from mouse keratinocytes, was enhanced by histamine via the H1 receptor. We also found that prolonged treatment with an H1-antagonist was effective against pruritus through depression of the production of NGF, which is thought to be generated by keratinocytes. We conclude that DS-Nh mice can serve as a suitable model for gaining a better understanding of pruritus in AD, and that prolonged treatment with an H1-antagonist may be beneficial in patients with AD-associated pruritus.

MeSH terms

  • Animals
  • Antipruritics / therapeutic use
  • Cells, Cultured
  • Dermatitis, Atopic / complications*
  • Dermatitis, Atopic / metabolism
  • Dermatitis, Atopic / pathology
  • Disease Models, Animal*
  • Histamine / metabolism
  • Histamine / pharmacology
  • Histamine H1 Antagonists, Non-Sedating / therapeutic use
  • Immunoglobulin E / blood
  • Keratinocytes / drug effects
  • Keratinocytes / metabolism
  • Loratadine / therapeutic use
  • Male
  • Mast Cells / pathology
  • Mice
  • Mice, Inbred Strains
  • Nerve Growth Factor / biosynthesis
  • Nerve Growth Factor / metabolism
  • Pruritus / drug therapy
  • Pruritus / etiology*
  • Pruritus / metabolism
  • Skin / metabolism
  • Specific Pathogen-Free Organisms

Substances

  • Antipruritics
  • Histamine H1 Antagonists, Non-Sedating
  • Immunoglobulin E
  • Loratadine
  • Histamine
  • Nerve Growth Factor