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Physiological levels of testosterone kill salmonid leukocytes in vitro

January 1, 1997

Adult spring chinook salmon (Oncorhynchus tshawytscha) elaborate high plasma concentrations of testosterone during sexual maturation, and these levels of testosterone have been shown to reduce the salmonid immune response in vitro. Our search for the mechanism of testosterone's immunosuppressive action has led to the characterization of an androgen receptor in salmonid leukocytes. In the present study we examined the specific effects that testosterone had on salmonid leukocytes. Direct counts of viable leukocytes after incubation with and without physiological levels of testosterone demonstrate a significant loss of leukocytes in cultures exposed to testosterone. At least 5 days of contact with testosterone was required to produce significant immunosuppression and addition of a 'conditioned media' (supernatant from proliferating lymphocytes not exposed to testosterone) did not reverse the immunosuppressive effects of testosterone. These data lead us to conclude that testosterone may exert its immunosuppressive effects by direct action on salmonid leukocytes, through the androgen receptor described, and that this action leads to the death of a significant number of these leukocytes.

Citation Information

Publication Year 1997
Title Physiological levels of testosterone kill salmonid leukocytes in vitro
DOI 10.1006/gcen.1996.6858
Authors C.H. Slater, C.B. Schreck
Publication Type Article
Publication Subtype Journal Article
Series Title General and Comparative Endocrinology
Index ID 70019883
Record Source USGS Publications Warehouse