Investigations on human lutropin from pituitary gland and urine

Two newly isolated monoclonal anti-beta hLH antibodies did not recognize both human chorionic gonadotropin (hCG) and three synthetic peptide fragments corresponding to beta hLH sequence. These antibodies were applied for ELISA of human luteinizing hormone (hLH), however, sensitivities of these assays were much lower than those with two other monoclonal antibodies obtained earlier in our laboratory. No significant differences between assays of hLH from pituitary and urine with 6 different pairs of monoclonal antibodies (4 anti-beta and 1 anti-alpha-subunit) were noticed. The highest hLH concentration in urine samples collected during 53 menstrual cycles of 6 women was demonstrated at different times of the day. In 14 out of 52 "preovulatory urine" portions, preserved for several weeks, over 80% increase of assayed hLH was shown. The highest assays of hLH from pituitary and urine were noted at pH 7.5-9.0. Using affinity chromatography the whole pituitary hLH was bound to ConA-Sepharose column and was eluted with alpha-methyl-D-mannoside as a single peak. However, a small part of hLH from urine was eluted from the column as non retarded peak. When HPLC analysis with DEAE column was performed, pituitary hLH was separated in two fractions while lutropin from urine was eluted as a single peak.