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Oxytocin contracts the human uterus at term by inhibiting the myometrial Ca2+-extrusion pump

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Bioscience Reports

Abstract

The sarcolemma of smooth-muscle ceils from human pregnant myometrium possesses a high-affinity Ca2+-ATPase, which has the characteristics of an active Ca2+-extrusion pump. This pump enzyme, either membrane-bound or solubilized, was strongly inhibited by oxytocin (half-maximal inhibition at about 4 μU/ml or 10 pM). However, under similar conditions, oxytocin did not inhibit Ca2+extrusion ATPase of the erythrocyte membrane. The inhibitory concentrations of oxytocin correspond to hormone plasma levels which initiate spontaneous labor.

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References

  • Akerman KEO & Wikström MKF (1979) (Ca2++Mg2+)-stimulated ATPase activity of rabbit myometrium plasma membrane is blocked by oxytocin. FEBS Lett.97, 283–287.

    PubMed  Google Scholar 

  • Berde B & Boissonas RA (1968) Basic pharmacological properties of synthetic analogues and homologues of the neurohypophysial hormones. In: Handbook of Experimental Pharmacology (Berde B, ed), vol 23, pp 802–870, Springer Verlag, Berlin.

    Google Scholar 

  • Carafoli E & Zurini M (1982) The Ca2+-pumping ATPase of plasma membranes. Biochim. Biophys. Acta683, 279–301.

    PubMed  Google Scholar 

  • Carafoli E, Inesi G & Rosen BP (1984) Calcium transport across biological membranes. In: Calcium and Its Role in Biology (Siegel A, ed), pp 129–186, Marcel Dekker, New York.

    Google Scholar 

  • Crankshaw DJ, Branda LA, Matlib MA & Daniel EE (1978) Localization of the oxytocin receptor in the plasma membrane of rat myometrium. Eur. J. Biochem.86, 481–486.

    PubMed  Google Scholar 

  • Daniel EE, Grover AK & Kwan CY (1982) Isolation and properties of plasma membrane from smooth muscle. Fed. Proc.41, 2898–2904.

    PubMed  Google Scholar 

  • Fabiato A & Fabiato F (1979) Calculator programs for computing the composition of the solutions containing multiple metals and ligands used for experiments in skinned muscle cells. J. Physiol. (Paris)75, 463–505.

    Google Scholar 

  • Fuchs AR (1983) The role of oxytocin in parturition. Curr. Topics Exptl. Endocrinol.4, 231–265.

    Google Scholar 

  • Hollenberg MD (1981) Polypeptide hormone receptors. In: Advanced Cell Biology (Schwartz LM & Azar MM, eds), pp 325–337, van Nostrand Reinhold, New York.

    Google Scholar 

  • Litman D, Hsu CJ & Marchesi VT (1980) Evidence that spectrin binds to macromolecular complexes on the inner surface of the red cell membrane. J. Cell Sci.42, 1–22.

    PubMed  Google Scholar 

  • Penniston JT (1983) Plasma membrane Ca2+-ATPases as active Ca2+ pumps. In: Calcium and Cell Function (Cheung WY, ed), vol 4, pp 99–149, Academic Press, New York.

    Google Scholar 

  • Popescu LM & Ignat P (1983) Calmodulin-dependent Ca2+-pump ATPase of human smooth muscle sarcolemma. Cell Calcium4, 219–235.

    PubMed  Google Scholar 

  • Popescu LM & Ignat P (1984) Calcium-extrusion pump of the smooth muscle cell membrane. In: Water and Ions in Biological Systems (Pullman B, Vasilescu V & Packer L, eds), in press, Plenum Press, New York.

    Google Scholar 

  • Popescu LM, Panoiu C, Toescu EC & Nutu O (1984a) Prostaglandins E2 and F2alpha inhibit the sarcolemmal Ca2+ extrusion pump of human myometrium at term. In: Prostaglandins and Membrane Ion Transport (Braquet P et al., eds), pp 217–222, Raven Press, New York.

    Google Scholar 

  • Popescu LM, Panoiu C, Nutu O & Toescu EC (1984b) Oxytocin and prostaglandins (E2 and F2alpha inhibit Ca2+-extrusion pump of human pregnant myometrium. Fed. Proc.43, 497.

    Google Scholar 

  • Roos I, Crompton M & Carafoli E (1980) The role of inorganic phosphate in the release of Ca2+ from rat liver mitochondria. Eur. J. Biochem.110, 319–325.

    PubMed  Google Scholar 

  • Soloff MS & Swartz TL (1974) Characterization of a proposed oxytocin receptor in the uterus of the rat and sow. J. Biol. Chem.249, 1376–1381.

    PubMed  Google Scholar 

  • Soloff MS & Sweet P (1982) Oxytocin inhibition of (Ca2++Mg2+)-ATPase activity in rat myometrium plasma membranes. J. Biol. Chem.257, 10687–10693.

    PubMed  Google Scholar 

  • van Breemen C, Aaronson P & Loutzenhiser R (1979) Sodium-calcium interactions in mammalian smooth muscle. Pharmacol. Rev.30, 167–208.

    Google Scholar 

  • Wikland M, Lindblom B, Wilhelmsson L & Wiqvist N (1982) Oxytocin, prostaglandins, and contractility of the human uterus at term pregnancy. Acta Obstet. Gynecol. Scand.61, 467–472.

    PubMed  Google Scholar 

  • Wuytack F, De Schutter G, Verbist J & Casteels R (1983) Antibodies to the calmodulin-binding Ca2+-transport ATPase from smooth muscle. FEBS Lett.154, 191–195.

    PubMed  Google Scholar 

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Authors and Affiliations

  1. Department of Cell Biology and Histology, Faculty of Medicine, PO Box 35-10, 35, Bucharest, Romania

    L. M. Popescu, O. Nutu & Cristina Panoiu

Authors
  1. L. M. Popescu
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  2. O. Nutu
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  3. Cristina Panoiu
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Popescu, L.M., Nutu, O. & Panoiu, C. Oxytocin contracts the human uterus at term by inhibiting the myometrial Ca2+-extrusion pump. Biosci Rep 5, 21–28 (1985). https://doi.org/10.1007/BF01117437

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  • DOI: https://doi.org/10.1007/BF01117437

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