[en] A method is described for the purification of canine prolactin, involving preparative isoelectrofocusing. Canine prolactin has a molecular weight of 23 000 daltons, an isoelectric point of 5.7 and exhibits a high degree of homogeneity in polyacrylamide gels stained by means of a silver method. A specific, homologous radioimmunoassay is described using the Bolton-Hunter method for preparation of the labelled ligand, with a sensitivity of 1.1 ng/tube. Basal plasma prolactin levels of 2-4 ng/ml obtained through the oestrous cycle remained fairly constant but a rise of 9 ng/ml was found at the end of disoetrus in nonpregnant bitches. Level also rose 30 days after mating to reach a peak of about 50 ng/ml near parturition and during early lactation.
Disciplines :
Veterinary medicine & animal health
Author, co-author :
De Coster, R.; Janssen Pharmaceutica Research Laboratories > Department of Oncology
Beckers, Jean-François ; Université de Liège - ULiège > Dept of Obstetrics and Pathology of Reproduction
Beerens, D.; Janssen Pharmaceutica Research Laboratories > Department of Oncology
De Mey, J.; Janssen Pharmaceutica > Dept of Oncology - B2340 Beerse Belgium
Language :
English
Title :
A homologous radioimmunoassay for canine prolactin: plasma levels during the reproductive cycle