A normal ovulatory woman with hyperprolactinemia: presence of anti-prolactin autoantibody and the regulation of prolactin secretion

Abstract

We present the case of a normal ovulatory woman with marked hyperprolactinemia and no evidence of a pituitary adenoma on CT and MRI. Gel filtration studies showed that most immunoreactive PRL was eluted as 150K–170K macroprolactin. Anti-PRL autoantibody was detected and Scatchard analysis revealed a low-affinity (the association constant: 1.29×107 l/mol), high-capacity (the maximal binding capacity: 1174 μg/l) antibody. Dopamine had little suppressive effect on PRL levels and an anti-dopaminergic agent elicited an augmented response of PRL secretion. These results suggest that the presence of anti-PRL autoantibody may delay the clearance of PRL and/or may alter the central regulation of PRL secretion.