[Biological and immunological characterization of human luteinizing hormone in plasma discharged by LH-RH infusion in normal adult women].
Five hundred micrograms synthetic LH-RH was infused for 2 hours in women having a normal menstrual cycle. Measurement of the plasma hLH level revealed two phases of hLH discharge; i.e. an acute and a delayed discharge (plasma pools I and II, respectively). These plasma pools were subjected to a column isoelectrofocusing (IEF) fractionation. The IEF fractionation separated plasma LH in both plasma pools into 6 distinct species; A (pI: 9.03 +/- 0.11), B (8.60 +/- 0.10), C (8.12 +/- 0.13), D (7.67 +/- 0.09), E (7.24 +/- 0.10), and F (acidic LH). The ratio of biological to immunological LH activities in each species was determined after concentration by ultrafiltration and found to be 1.12, 2.09, 2.21, 1.87, 1.29, and 0.49, respectively. The acidic LH was more enriched in plasma pool II throughout the menstrual cycle than in its counterpart. The majority of LH activity was found in B, C and D. The relative amount of LH migrating in the high alkaline region (A) was greater in plasma pool I of the late follicular phase where the secretion of the hormone was depressed. In conclusion, LH subpopulations separated by IEF may represent the stage of molecular maturation of the hormone. The acidic LH is probably the LH newly synthesized and not well processed. The LH species possessing alkaline pIs (B, C and D) are mature types of the hormone. The LH migrating in the high alkaline region (A) may be the LH of over-maturation.
D000328:Adult; D005260:Female; D005498:Follicular Phase; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007525:Isoelectric Focusing; D008183:Luteal Phase; D007986:Luteinizing Hormone / Q000097:blood* / Q000276:immunology; D013223:Statistics as Topic; D014462:Ultrafiltration
D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone