RÉSUMÉ
To investigate the effects of brazilin on the altered immune functions in the early phase of halothane intoxication in mice, several immune functions were investigated. Halothane was found to alter the immune functions which lead to hepatitis by autoimmune-mediated process. Based on the fact that immunomodulation at an initial step of autoimmune diseases is effective to prevent or control the diseases, in the present study the effects of brazilin on the altered immune functions in the early phase of halothane intoxication of C57BL/6 mice were investigated. By the treatment of halothane, delayed type hypersensitivity (DTH) and mitogen (ConA, LPS) induced proliferation of splenocytes were significantly increased and suppressor cell activity and mixed lymphocyte reaction (MLR) were decreased in C57BL/6 mice. But IgM plaque forming cells (PFCs) were not significantly changed. All the parameters tested were changed in homing patterns by the treatment with brazilin. But brazilin significantly increased IgM PFCs to higher than the normal level.
Sujet(s)
Benzopyranes/pharmacologie , Halothane/toxicité , Hypersensibilité retardée , Activation des lymphocytes/effets des médicaments et des substances chimiques , Lymphocytes T régulateurs/immunologie , Animaux , Cellules cultivées , Concanavaline A , Transfusion d'érythrocytes , Femelle , Technique des plaques d'hémolyse , Immunoglobuline M/immunologie , Lipopolysaccharides , Test de culture lymphocytaire mixte , Souris , Souris de lignée C57BL , Ovis , Lymphocytes T régulateurs/effets des médicaments et des substances chimiquesRÉSUMÉ
Previously we reported that brazilin, the main principle of Caesalpinia sappan, was able to improve the altered immune functions caused by halothane administration in mice. To elucidate the mechanisms of its immunomodulating activities, the effects of brazilin on the functions of T cells and splenic cellularity were investigated. Brazilin decreased splenic cellularity and IL-2 production which had been augmented in mice treated with halothane (21.5% in olive oil, 10 mmol/kg) for 4 consecutive days whereas the reduced expression of IL-2 receptors by ConA or standard IL-2 was increased by brazilin treatment. These data indicate that halothane induced a dysfunction of T cells resulting in abnormal immune responses and these altered immune functions might be improved mainly by affecting the function of T cells.