Purification and characterization of glycosylated and non-glycosylated forms of prolactin from the dromedary (Camelus dromedarius)

1. Camel prolactin (camPRL) was isolated from the insoluble residue left after extraction of the gonadotropins FSH and LH from a single batch of one-humped camels (Camelus dromedarius) pituitaries. 2. Several isoforms of camPRL were isolated and characterized. 3. Glycosylated and non-glycosylated forms of camPRL were separated by affinity chromatography on Con-A Sepharose. 4. The glycosylated form represented more than 20% of total camPRL and was found to be only 10-20% as active as the non-glycosylated form in its ability to bind to rabbit mammary gland PRL receptors and to stimulate the proliferation of Nb2 cells.