Abstract
The present study was designed to evaluate the immunological outcome resulting from experimental conditions involving different corticosterone and prolactin ratios in rats. One set of experiments was conducted to assess the effects of prolactin and corticosterone on the in vitro mitogen-induced proliferation of spleen lymphocytes from animals previously submitted to the manipulation of their glucocorticoid status throughout adrenalectomy (ADX) and/or exposure to acute stress. The results indicated that prolactin (5 x 10(-9) M) induced a significant increase in concanavalin A- (ConA) induced proliferation of splenocytes only from ADX-control, unstressed, rats. However, a lower dose of prolactin (10(-9) M) failed to influence lymphoproliferation. Corticosterone (2 x 10(-8) and 10(-7) M) induced a dose-dependent reduction in lymphocyte proliferation in all experimental groups. Further experiments were conducted to study the relative potency of prolactin to antagonize the in vitro corticosterone-induced suppression of ConA-stimulated lymphocytes. The results showed, on the one hand, that higher doses of prolactin (10(-8) and 5 x 10(-8) M) were effective in stimulating ConA-induced lymphocyte proliferation in control, undisturbed, rats. They also showed that when prolactin and corticosterone are simultaneously added to the cultures, the immunostimulatory effect induced by a dose of 10(-8) M of prolactin can either predominate over a weak suppressive action of corticosterone (2 x 10(-8) M) or totally antagonize to normal values a marked immunosuppression induced by a higher dose of corticosterone (10(-7) M). These data support the view that different ratios between prolactin and corticosterone concentrations can result in differential immunological outcome.(ABSTRACT TRUNCATED AT 250 WORDS)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.