Information de reference pour ce titreAccession Number: | 00004872-199917030-00012.
|
Author: | Read, Mark A. 1,3; Leitch, Ian M 2; Giles, Warwick B. 2; Bisits, Andrew M. 2; Boura, Alan L.A. 2; Walters, William A.W. 2
|
Institution: | (1)Division of Obstetrics and Gynaecology, John Hunter Hospital, Newcastle, New South Wales, Australia (2)Discipline of Reproductive Medicine, The University of Newcastle, Callaghan, New South Wales, Australia.
|
Title: | |
Source: | Journal of Hypertension. 17(3):389-396, March 1999.
|
Abstract: | Objectives: To measure in-vitro responses to the thromboxane A2 (TxA2) mimetic U46619 in the fetal placental vasculature of human placentae from normotensive women and those with pre-eclampsia. Furthermore, to compare fetal vascular responses to endothelin-1, 5-hydroxytryptamine, potassium chloride (KCl) and prostacyclin (PGI2) in placentae from normal or pre-eclamptic pregnancies.
Methods: Single placental lobules of intact placentae were bilaterally perfused in situ (fetal and maternal) with constant flows of Krebs' solution. Changes in fetal arterial perfusion pressure during intra-arterial infusion of vasoactive agents were recorded. Fetal placental vasoconstrictor concentration response curves were obtained to U46619 (0.01-300 nmol/l), endothelin-1 (0.4-160 nmol/l), KCl (3-300 mmol/l) and 5-hydroxytryptamine (0.03-30 [mu]mol/l). In addition, vasodilator concentration response curves were obtained for PGI2 (1.2-350 nmol/l) in the fetal placental circulation during submaximal increases in perfusion pressure with prostaglandin F2[alpha] (PGF2[alpha]; 0.7-2.0 [mu]mol/l).
Results: The maximum increase in perfusion pressure caused by U46619 in placentae from normotensive women was 194 +/- 25 mmHg. The maximum response to U46619 was significantly reduced in the placentae from women with pre-eclampsia (104 +/- 21 mmHg). In contrast, there were no differences in constrictor responses to endothelin-1, 5-hydroxytryptamine and KCl, or in dilator responses to PGI2 in placentae obtained from either normotensive women or those with pre-eclampsia.
Conclusion: TxA2 receptor-mediated vasoconstriction is reduced in the fetal vasculature of placentae from women with pre-eclampsia, possibly to compensate for the increased levels of TxA2 seen in these conditions.
(C) 1999 Lippincott Williams & Wilkins, Inc.
|
Author Keywords: | thromboxane; placenta; pre-eclampsia; U46619; hypertension; prostacyclin; pregnancy.
|
References: | 1 Witlin AG, Sibai BM. Hypertension in pregnancy: current concepts of preeclampsia. Annu Rev Med 1997; 48:115-127.
2 Vinatier D, Monnier JC. Pre-eclampsia: physiology and immunological aspects. Eur J Obstet Gynaecol, Reproduct Biol 1995; 61:85-97.
3 Brown MA. The physiology of pre-eclampsia. Clin Exp Pharmacol Physiol 1995; 22:781-791.
4 Meagher EA, Fitzgerald GA. Disordered eicosanoid formation in pregnancy-induced hypertension. Circulation 1993; 88:1324-1333.
5 Walsh SW, Wang Y. Trophoblast and placental villous core production of lipid peroxides, thromboxane, and prostacyclin in preeclampsia. J Clin Endocrinol Metab 1995; 80:1888-1893.
6 Walsh SW. Physiology of low dose aspirin therapy for the prevention of preeclampsia. Semin Perinatol 1990; 14:152-170.
7 Nelson DM, Walsh SW. Thromboxane and prostacyclin production by different compartments of the human placental villus. J Clin Endocrinol Metab 1989; 68:676-683.
8 Fitzgerald DJ, Mayo G, Catella F, Entman SS, Fitzgerald GA. Increased thromboxane biosynthesis in normal pregnancy is mainly derived from platelets. Am J Obstet Gynecol 1987; 157:325-330.
9 Reilly RD, Russell PT. Neurohistochemical evidence supporting an absence of adrenergic and cholinergic innervation in the human placenta and umbilical cord. Anat Rec 1977; 188:277-286.
10 CLASP (Collaborative Low-dose Aspirin Study in Pregnancy) Collaborative Group. CLASP: a randomised trial of low-dose aspirin for the prevention and treatment of pre-eclampsia among 9364 pregnant women. Lancet 1994; 343:619-629.
11 Leitch IM, Read MA, Boura AL, Walters WA. Effect of inhibition of nitric oxide synthase and guanylate cyclase on hydralazine-induced vasodilatation of the human fetal placental circulation. Clin Exp Pharmacol Physiol 1994; 21:615-622.
12 Petersen OB, Skajaa K, Svane D, Gregersen H, Forman A. The effects of dihydralazine, labetalol and magnesium on the isolated, perfused human placental cotyledon. Br J Obstet and Gynaecol 1994; 101:871-878.
13 Montan S, Anandakumar C, Arulkumaran S, Ingermarsson I, Ratnam SS. Effects of methyldopa on uteroplacental and fetal hemodynamics in pregnancy induced hypertension. Am J Obstet Gynecol 1993; 168:152-156.
14 Bowman WC, Rand MJ. In: Bowman WC, Rand MJ (editors): Textbook of pharmacology. Second edition. Oxford, UK: Blackwell; 1980. pp. 41.41-41.48.
15 Glance DG, Elder MG, Myatt L. The action of prostaglandins and their interactions with angiotensin II in the isolated perfused human placental cotyledon Br J Obstet Gynaecol 1986; 93:488-494.
16 Templeton AG, McGrath JC, Whittle MJ. The role of endogenous thromboxane in contractions to U46619, oxygen, 5-HT and 5-CT in the human isolated umbilical artery. Br J Pharmacol 1991; 103:107-1084.
17 Toyofuku K, Nishimura J, Kobayashi S, Nakano H, Kanaide H. Effects of U46619 on intracellular Ca++ concentration and tension in human umbilical artery. Am J Obstet Gynecol 1995; 172:1414-1421.
18 Hirata M, Hayashi Y, Ushilubi F, Yokota Y, Kageyama R, Nakanishi S, et al. Cloning and expression of cDNA for a human thromboxane A2 receptor. Nature 1991; 349:617-620.
19 Raychowdhury MK, Yukawa M, Collins LJ, McGrail SH, Kent KC, Ware JA. Alternative splicing produces a divergent cytoplasmic tail in the human endothelial thromboxane A2 receptor. J Biol Chem 1994; 269: 19256-19261.
20 Woodworth SH, Li X, Lei ZM, Rao CV, Yussman MA, Spinnato JA 2nd, et al. Eicosanoid biosynthetic enzymes in placental and decidual tissues from preeclamptic pregnancies: increased expression of thromboxane-A2 synthase gene. J Clin Endocrinol Metab 1994; 78:1225-1231.
21 Kent KC, Collins LJ, Schwerin FT, Raychowdhury MK, Ware JA. Identification of functional PGH2/TxA2 receptors on human endothelial cells Circ Res 1993; 72:958-965.
22 Wilkes BM, Mento PF, Hollander AM. Reduced thromboxane receptor affinity and vasoconstrictor responses in placentae from diabetic pregnancies. Placenta 1994; 15:845-855.
23 Van Assche FA, Spitz B, Hanssens M, Van Geet C, Arnout J, Vermylen J. Increased thromboxane formation in diabetic pregnancy as a possible contributor to pre-eclampsia. Am J Obstet Gynecol 1993; 168:84-87.
24 Wilkes BM, Mento PF, Hollander AM, Giraudi EP. Thromboxane and prostacyclin binding in placentae of pregnancies complicated by preeclampsia Proceedings 10th World Congress, International Society for the Study of Hypertension in Pregnancy 1996; A284:243.
25 Murray R, Shipp E, Fitzgerald GA. Prostaglandin endoperoxide/thromboxane A2 receptor desensitization. Cross-talk with adenylate cyclase in human platelets. J Biol Chem 1990; 265:21670-21675.
26 Inayatulla A, Chemtob S, Nuwayhid B, Varma DR. Response of placental arteries from normotensive and pre-eclamptic women to endogenous vasoactive agents. Am J Obstet Gynecol 1993; 168:869-874.
27 Macara L, Kingdom JCP, Kaufmann P, Kohnen G, Hair J, More IAR, et al. Structural analysis of placental terminal villi from growth-restricted pregnancies with abnormal umbilical artery Doppler waveforms. Placenta 1996; 17:37-48.
28 Wilkes BM, Macica CM, Mento PF. Endothelin-1 conversion and receptor characterization in human placental arteries. Am J Physiol 1994; 267:E242-E249.
29 Marin J, Revirego J, Fernandez-Alfonso MS. Ability of ketanserin to block different receptors in human placental vessels. J Pharm Pharmacol 1990; 42:217-220.
30 Allen J, Forman A, Maigaard S, Jespersen LT, Andersson KE. Effect of endogenous vasoconstrictors on maternal intramyometrial and fetal villous arteries in pre-eclampsia. J Hypertens 1989; 7:529-536.
31 Cruz MA, Gonzalez CG, Gallardo V, Lagos M, Albornoz J. Venous placental reactivity to serotonin in normal and pre-eclamptic gestants. Gynecol Obstet Invest 1993; 36:148-152.
32 Taniguchi K. Vasospastic action of serotonin on the umbilical artery in normal and preeclamptic patients. J Obstet Gynaecol 1995; 21:37-42.
33 Bodelsson G, Marsal K, Stjernquist M. Reduced contractile effect of endothelin-1 and noradrenalin in human umbilical artery from pregnancies with abnormal umbilical artery flow velocity waveforms. Early Hum Devel 1995; 42:15-28.
34 Tsunoda K, Abe K, Yoshinga K, Furuhashi N, Kimura H, Tsujiei M, et al. Maternal and umbilical venous levels of endothelin in women with preeclampsia J Hum Hypertens 1992; 6:61-64.
35 Taniguchi K, Okatani Y, Sagara Y. Serotonin metabolism in the fetus in preeclampsia. Asia Oceania J Obstet Gynaecol 1994; 20:77-86.
36 Wolff K, Nisell H, Carlstrom K, Kublickene K, Hemsen A, Luneel NO, et al. Endothelin-1 and big endothelin levels in normal term pregnancy and in preeclampsia. Regul Pept 1996; 67: 211-216.
37 Schneider H. Techniques: in vitro perfusion of human placenta. In: Sastry R (editor): Placental toxicology. Boca Raton: CRC Press; 1995. pp. 1-26.
38 Boura ALA, Leitch IM, Read MA, Walters WAW. The control of vascular resistance in the human placenta. Trophoblast Research 1998; 11:299-314.
39 Wang Y, Walsh SW. Aspirin inhibits both lipid peroxides and thromboxane in preeclamptic placentas. Free Radic Biol Med 1995; 18:585-591.
40 Sibai BM, Mirro R, Chesney CM, Leffler C. Low-dose aspirin in pregnancy. Obstet Gynecol 1989; 74:551-557.
|
Language: | English.
|
Document Type: | Original article.
|
Journal Subset: | Clinical Medicine.
|
ISSN: | 0263-6352
|
NLM Journal Code: | iew, 8306882
|
Annotation(s) | |
|
|