Pregnant or not pregnant-systemic or pulmonary hypertension induced by thromboxane A2 and deficiency of prostaglandins: A hypothesis

György Losonczy, Gail Brown, Rocco C. Venuto

Research output: Contribution to journalArticle

2 Citations (Scopus)


Background: Dysfunctional vascular endothelium with deficient production of prostacyclin (PGI2), persistent activation of platelets, enhanced release of thromboxane A2 (TXA2), and vasospasm are common features of two vascular disorders, both of which are of unknown origin and affect exclusively or mainly women of childbearing age: preeclampsia (PE) and primary pulmonary hypertension (PPH). The association of high TXA2/PGI2 ratio with systemic hypertension in pregnant but with pulmonary hypertension in nonpregnant women is intriguing. Hypothesis: Based on experimental data collected from intact nonpregnant and pregnant rabbits, isolated and perfused lung preparations, and TXA2 receptor studies performed on pulmonary arterial membranes, we hypothesize that in the nonpregnant state the pulmonary resistance vessels may form the primary target site of TXA2, and that during pregnancy the sensitivity of these vessels to TXA2 may be blunted simultaneously with enhanced systemic vascular sensitivity to this eicosanoid. Such a reciprocal change of vascular TXA2 sensitivity could explain the association of high TXA2/PGI2 ratio with PPH in nonpregnant women and with systemic hypertension in pregnant women.

Original languageEnglish
Pages (from-to)281-285
Number of pages5
JournalHypertension in Pregnancy
Issue number3
Publication statusPublished - Jan 1 1996


ASJC Scopus subject areas

  • Internal Medicine
  • Obstetrics and Gynaecology

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