Expression of G-protein-coupled receptor kinases in pregnant term and non-pregnant human myometrium

Sep 1, 1999The Journal of endocrinology

Levels of G-protein-coupled receptor regulators in the muscle layer of the uterus during pregnancy and non-pregnancy

AI simplified

Circadian Biology on OpenScience ↗PubMed ↗DOI ↗

Abstract

Human myometrium expresses GRK subtypes 2, 4gamma, 5, and 6, with GRK2 specific to pregnant term tissue.

GRK2 is absent in non-pregnant myometrium but is present in pregnant term tissue.
GRK6 is found at significantly higher levels in pregnant term myometrium compared to non-pregnant tissue.
The expression of GRK subtypes may be linked to the regulation of uterine contractility at term.
GRK3 and isoforms GRK4alpha, beta, and delta are not detected in myometrial tissue.
Understanding the role of GRKs in receptor desensitisation could inform research on uterine contractility disorders.

AI simplified

There is evidence for hormonal receptor desensitisation in human myometrium, but little is known about the mechanisms involved in the loss of myometrial response to agonists such as beta(2)-adrenergic agonists, prostaglandin gamma and oxytocin. It is well known that the receptors for these hormones are coupled to G-proteins. The first step of receptor desensitisation is the phosphorylation of activated receptors by a G-protein-coupled receptor kinase (GRK). GRKs are members of a multigene family and the various subtypes differ in their localisation, regulation and mode of action. We have used Western blotting and reverse transcription PCR to identify the GRKs present in human myometrium from pregnant and non-pregnant women as well as in cultured human myometrial cells. We have found that human myometrium expresses the GRK subtypes 2, 4gamma, 5 and 6. On the other hand, GRK3 and the isoforms GRK4alpha, beta and delta were not found in myometrial tissue. Our data indicate that GRK2 is only expressed in pregnant term myometrium and is not found in non-pregnant tissue. Moreover, GRK6 appears to be expressed at a much higher level in pregnant term tissue than in non-pregnant myometrium. Our observations suggest that GRK2 and GRK6 may contribute to the regulation of uterine contractility at term. Further work is necessary to determine whether GRKs and receptor desensitisation play a role in disorders of uterine contractility.

Full Text

Full text is available at the source.

View full text (HTML) ↗View full text ↗

Expression of G-protein-coupled receptor kinases in pregnant term and non-pregnant human myometrium

Abstract

Full Text

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief

Abstract

Full Text

Related papers

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief