[Importance of prolactin isoforms on ovary function in hyperprolactinemic women]

Gel filtration chromatography in Sephadex G-100, was used to analyse the molecular heterogeneity of prolactin (PRL) in serum from seven hyperprolactinemic women. Chromatographic patterns from samples obtained from four women with hyperprolactinemia and normal menstrual cycles showed a predominance of big-big PRL (79%). In contrast, three women with hyperprolactinemia and amenorrhea presented a chromatographic pattern with predominance of little PRL (69%). The results suggest that the molecular heterogeneity of PRL found is associated with menstrual cycles disorders and hence with ovarian function. Normal ovarian function in hyperprolactinemic patients seems to be associated to increased levels of big-big PRL and altered ovarian function to high level of little PRL.