[Origin of the FSH + LH double activity of equine chorionic gonadotropin (eCG/PMSG)].
Abstract: The LH and FSH activities of equine choriogonadotropin (eCG) have been compared in several species with those of the highly purified homologous pituitary gonadotropins. The molar FSH/LH activity ratio of eCG determined by RRA is 0.20 in the pig, 0.25 in the rat and 0 in the horse. These data demonstrate the LH monospecificity of eCG in its own species as it is the case for hCG. We have also shown that equine LH exhibited a FSH-activity similar to that of eCG in the pig and in the rat but not in the horse. In the female rat, the binding activity to FSH receptors and the in vitro FSH activity of eCG are similar (about 0.005 X eFSH). In the male rat, the binding activity of eCG to FSH receptors is much higher (0.15 X eFSH) than its in vitro FSH activity (0.007 X eFSH). The behaviour of equine LH is similar to that of eCG in the four systems. Our data clearly indicate that the double activity of eCG is not unique to this molecule. Moreover, the double activity is not intrinsic to the eCG molecule since it depends on the species and the sex of the animal used as well as on the system used (RRA) or in vitro biological assay).
Publication Date: 1984-01-01 PubMed ID: 6442963
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- Comparative Study
- English Abstract
- Journal Article
Summary
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The research explores the dual Follicle-stimulating hormone (FSH) and Luteinizing hormone (LH) activity in equine chorionic gonadotropin (eCG), also known as pregnant mare serum gonadotropin (PMSG). The study identifies that eCG demonstrates LH-specific activity in horses, similar to human chorionic gonadotropin (hCG) in humans, but it displays FSH and LH activity in other species like pigs and rats. Additionally, the research indicates that the double activity of eCG is not exclusive to it and is mutable, depending on the species, sex of the animal, and the system used for measurement.
Comparison of LH and FSH Activities
- The research reports a comparison between the LH and FSH activities of eCG and the highly purified pituitary gonadotropins from various species. The FSH/LH activity ratio is determined through Radioimmunoassay (RRA).
- The FSH/LH activity ratio of eCG in pigs, rats, and horses was found to be 0.20, 0.25, and 0 respectively, indicating that eCG has specifically LH activity in horses, similar to hCG in humans.
FSH-Activity in Equine LH
- The split FSH activity of equine Luteinizing hormone (LH) was found to be like that of eCG in pigs and rats, but not in horses. This suggests that the species of the test subject can affect the LH/FSH activity of eCG.
Binding Activity to FSH Receptors and FSH Activity
- In female rats, the binding activity of eCG to FSH receptors and the in vitro FSH activity of eCG were found to be similar.
- In male rats, the binding activity of eCG to FSH receptors was found to be significantly higher than its in vitro FSH activity.
Double Activity of eCG
- The research concludes that the dual FSH and LH activity of eCG is not unique to this type of hormone. Furthermore, this dual activity doesn’t originate inherently from the eCG molecule.
- Factors such as the type of animal species, sex of the species, and the kind of system used for measurement (like RRA or in vitro biological assay) influence the double activity.
Cite This Article
APA
Combarnous Y, Guillou F, Martinat N, Cahoreau C.
(1984).
[Origin of the FSH + LH double activity of equine chorionic gonadotropin (eCG/PMSG)].
Ann Endocrinol (Paris), 45(4-5), 261-268.
Publication
Researcher Affiliations
MeSH Terms
- Animals
- Binding, Competitive
- Chemical Phenomena
- Chemistry
- Female
- Follicle Stimulating Hormone / pharmacology
- Gonadotropins, Equine / pharmacology
- Horses
- Humans
- Luteinizing Hormone / pharmacology
- Male
- Models, Chemical
- Radioligand Assay
- Rats
- Species Specificity
- Swine
Citations
This article has been cited 2 times.- de Andrade ABP, Morais MCC, Rangel PSC, Oliveira MEF, Souza-Fabjan JMG, Fonseca JF. Effect of eCG in a short-term synchronization treatment on ovarian status, estrus synchrony, and ovulation in dairy goats managed under tropical conditions. Trop Anim Health Prod 2021 Apr 5;53(2):246.
- Matvere A, Teino I, Varik I, Kuuse S, Tiido T, Kristjuhan A, Maimets T. FSH/LH-Dependent Upregulation of Ahr in Murine Granulosa Cells Is Controlled by PKA Signaling and Involves Epigenetic Regulation. Int J Mol Sci 2019 Jun 23;20(12).
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