GPER1 and synovitis: In this study, we presented gender-specific differences in the expression of GPR30 in the synovial membrane, cartilage and DG of the hippocampus and their correlation with the clinical score, Krenn synovitis score, Mankin osteoarthritis score, number of Iba-1+ cells in the hippocampus and serum TNF and IL-17A levels.