Endocrine Abstracts

Macroprolactin is a high molecular mass prolactin isoform found in some normal individuals. The most common form of macroprolactin arises from binding of prolactin to IgG ('big-big' prolactin), with a molecular mass 150-170 kD. A further prolactin isoform of intermediate size ('big' prolactin, 50-60 kD), has also been described but the nature and significance of this form is less clearly understood.We have previously described the effects of pregnancy in...

Macroprolactin(mPRL)is a high molecular weight form of prolactin(PRL)most commonly due to formation of a complex with IgG.The PRL in mPRL remains reactive in immunoassays for PRL and the complex has a longer plasma half life than monomeric PRL.mPRL is a common cause of hyperprolactinaemia but its origin is not known and the complex has minimal bioactivity in vivo.The clinical significance of hyperprolactinaemia due to mPRL is that it can cause diagnostic confusion and lead to ...