Caleb H. Slater

TL;DR: The magnitude of the steroid-induced immunosuppression was reduced during winter and increased again in spring, and Testosterone and cortisol administered together had a significantly greater effect than did either administered alone.

TL;DR: Plasma testosterone concentrations were low through the spring and early summer, concentrations began rising in late July and reached maximum levels by ovulation in September, and plasma gonadotropin I concentrations paralleled those of estradiol and exceeded gonadotropic levels prior to ovulation.

TL;DR: The data strongly suggest that androgen receptors exists in salmonid leukocytes and support the hypothesis that these receptors play a role in androgen induced immunosuppression.

TL;DR: The fact that in both years all endocrine and immune variables that correlated with each other also correlated with the date of sample, raises the question as to whether or not these are cause-and-effect relations.

TL;DR: It is concluded 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 leuk cells.