Adjuvant arthritis in the rat is associated with decreased binding of nuclear receptors to thyroid hormone responsive element in spleen extracts.

In vertebrates, thyroid hormone and its cognate nuclear receptors are involved in a complex arrangement of physiological and developmental function. Since thyroid hormone has also been shown to affect immune responses, we investigated the DNA binding status of T3 receptors of spleen nuclear extracts in a) rats with adjuvant arthritis (AA); b) adrenalectomized rats (ADX), and c) animals with adjuvant arthritis followed by adrenalectomy (AA + ADX). A marked diminution in the functional binding of nuclear thyroid hormone receptors to DR4 thyroid hormone responsive DNA element was found in the spleens of AA and AA + ADX rats when compared to a control group or ADX rats. The data based on in vivo experiments suggest that the nuclear receptor--thyroid hormone responsive element complex status within the cell nucleus may be altered in adjuvant arthritis.