Circadian changes of serum corticosterone, cytokine and locomotor activities in NC/Nga mice

• Published in: Japanese Journal of Pharmacology 2001, Vol.85 (suppl.1), p.119-119
• Main Authors: Iwao Arai, Yuki Hashimoto, Hidemi Shiomoto, Masumi Satoh, Takato Nikaidou, Michio Kurachi
• Format: Article
• Language: Japanese
• ISSN: 0021-5198

NC/Nga mice reared conventionally were spontaneously develop chronic skin lesion which is similar to human atopic dermatitis. Corticosterone is a powerful endogenous immuno-suppressant and antiinflammatory agent in many species. And cytokine is an endogenous immunostimulants. In the present study, circadian variations in serum corticosterone (SC), cytokine (IFN-γ, IL-4, IL-5, IL-12) levels and locomotor activity of NC/Nga mice were compared to those of BALB/c mice. Blood samples were collected from decapitated mice at 3：00, 9：00, 15：00 and 21：00. In NC/Nga mice, the SC level was lowest at 9：00 and was highest from 15：00 to 3：00. In contrast, the SC level of BALB/c mice was low in the morning, and was highest in the afternoon and evening. Serum cytokine levels in NC/Nga mice were always low. In BALB/c mice, overall, the serum cytokine level was highest at from 3：00 to 9：00, and was lowest at from 15：00 to 21：00. The cytokine levels were in inverse propotion to the SC levels. Moreover, the circadian rhythm of the locomotor activity of NC/Nga mice was not entrained with a light and dark cycle, but in BALB/c mice was closely entrained. What is entrained to circadian rhythm of NC/Nga mice is not clear yet. However, these circadian rhythm of NC/Nga mice were clearly different from that of BALB/c mice. These circadian changes may be related to the development of dermatitis in NC/Nga mice.