HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology

 

Corticosterone 21-acetate in vivo induces acute stress in chicken thymus: cell proliferation, apoptosis and cytokine responses

A. Franchini, E. Marchesini and E. Ottaviani

Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy

Offprint requests to: Prof. Enzo Ottaviani, Department of Animal Biology, via Campi 213/D, 41100 Modena, Italy. Fax: 059-205 5548. e-mail: ottaviani.enzo@unimore.it

 

Summary. In vivo effects of acute stress induced by corticosterone 21-acetate in male Gallus domesticus thymus are studied and the steroid actions are evaluated in terms of cell proliferation, apoptosis and cytokine response in 10- and 21-day-old chickens. Steroid treatment induced thymocyte apoptosis and cell death decreased in the cortical-medullar direction and was more evident in younger animals. 24 h after treatment, the observed effect was reversed. The mitotic activity and thymic cells containing cytokine-like molecules were also affected. Indeed, the acute stress stimulated cytokine immunoreactivity to anti-IL-1a, IL-6 and TNF-a antibodies both in epithelial cells and interdigitating cells located in medullar and cortical-medullar regions. The increased cytokine expression observed after 12 h was maintained after 24 h. The comparison between 10- and 21-day-old chickens showed a lower number of cells containing cytokine-like molecules in younger specimens. The present findings suggest that cytokines activated by acute stress in vivo could contribute to restoring immunological homeostasis and influence thymic glucocorticoid-mediated functions. Histol. Histopathol. 19, 693-699 (2004)

Key words: Gallus domesticus, Thymus, Corticosterone 21-acetate, Apoptosis, Mitosis, Cytokines

DOI: 10.14670/HH-19.693