ELEVATED SERUM PROLACTIN OR ELEVATED PROLACTIN CORTISOL RATIO ARE ASSOCIATED WITH AUTOIMMUNE PROCESSES IN SYSTEMIC LUPUS-ERYTHEMATOSUS AND OTHER CONNECTIVE-TISSUE DISEASES/

Objective. We investigated whether serum prolactin (Prl) alone or an i ncreased Prl/cortisol ratio correlated with the autoimmune processes i n systemic lupus erythematosus (SLE) and other connective tissue disea ses (CTD). Methods. Serum Prl, cortisol, cytokines, and autoantibodies were measured in 29 patients with SLE and 29 patients with other CTD by ELISA. The patients were clinically assessed. Results, Serum Prl wa s elevated in both SLE (p < 0.05) and other CTD (p < 0.01). Some patie nts with SLE had reduced serum cortisol levels. In SLE only, the Prl a nd cortisol levels were correlated (p < 0.05), suggesting a parallel a ctivation of the different neuroendocrine pathways. Both groups of pat ients showed significantly increased Prl/cortisol ratios (p < 0.01 in SLE and p < 0.05 in other CTD). In CTD other than SLE, increased tumor necrosis factor-alpha correlated with the elevated Prl/cortisol ratio (p < 0.05). In SLE, other CTD and control sera, elevated levels of Ig G anti-cardiolipin antibody (aCL) were accompanied by increased Prl (0 .01 < p < 0.05). In other CTD, the production of IgM aCL and IgG antit hyroglobulin was associated with increased levels of either Prl or cor tisol, respectively (p < 0.05 for both). In SLE, the production of IgA rheumatoid factor was increased with an elevated Prl/cortisol ratio ( p < 0.05). Moreover, in SLE only, strongly enhanced synthesis of IgG a nti-double stranded DNA, as well as IgG antithyroid microsomal antibod ies were accompanied by elevated Prl (p < 0.05 for both). Conclusion, In SLE and other CTD, increased Prl favored the autoimmune processes, which are reflected by the presence of higher titers of autoantibodies . In many cases, increased Prl was accompanied by elevated cortisol.