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Polyamine effects on human myometrial contractility.

Diarmaid D Houlihan·Michael C Dennedy·John J Morrison
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Abstract

OBJECTIVE: This study was undertaken to investigate the effects of the polyamine spermine on human uterine contractility. STUDY DESIGN: Under physiologic conditions, an isometric tension recording was performed in isolated myometrial strips from biopsy specimens obtained at elective cesarean delivery (n = 24 specimens) and from premenopausal hysterectomy specimens (n = 6 specimens). The effects of spermine (1 micromol/L-10 mmol/L in cumulative doses) on spontaneous, agonist-induced myometrial contractions were measured, and dose response curves were constructed. The pD(2) (-log EC(50)) values and the maximal inhibition values achieved were compared for spontaneous and agonist-induced contractions. RESULTS: Spermine exerted a potent relaxant effect on all spontaneous and agonist-induced myometrial contractions, with mean maximal inhibition values between 62.8% +/- 4.3% and 91.4% +/- 1.8% and pD(2) values between 2.66 +/- 0.23 and 4.01 +/- 0.20. Its inhibitory effect varied significantly with different contraction types (pD(2), P <.05; mean maximal inhibition, P <.001), and it was least potent on BAY K 8644-elicited contractions (pD(2), P <.05; mean maximal inhibition, P <.01). CONCLUSION: The polyamine spermine exerts a potent relaxant effect on human uterine tissue. This effect appears to be mediated, at least partially, by calcium antagonism. Polyamines may play a role in the maintenance of uterine quiescence during pregnancy.

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3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl esterAdrenergic alpha-AgonistsCalcium Channel AgonistsCesarean SectionFemaleGestational AgeGlyburideHumansHysterectomyMethylene BlueMyometriumOxytocinPhenylephrinePolyaminesPregnancySpermineUterine ContractionComparative StudyJournal Article

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Diarmaid D Houlihan, Michael C Dennedy, John J Morrison. 2002. Polyamine effects on human myometrial contractility.. https://doi.org/10.1067/mob.2002.122253

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