title: Experimental atherosclerosis: effects of oestrogen and atherosclerosis on thromboxane and prostacyclin formation.
abstract: We evaluated the effect of oestrogen and experimental atherosclerosis on the in vivo formation of thromboxane and prostacyclin in rabbits. Twenty-four New Zealand White rabbits were divided into four groups. One group received control diet, one group received control diet and oestrogen, one group received control diet supplemented with 1% cholesterol and one group received cholesterol supplemented diet and oestrogen during 3 months. The in vivo formation of thromboxane and prostacyclin were measured as 2,3-dinor-TxB2 and 2,3-dinor-6-keto-PGF1 alpha in urine by gas chromatography/mass spectrometry. All rabbits on cholesterol diet became hypercholesterolaemic and developed atherosclerosis. As in previous experiments cholesterol and oestrogen-treated rabbits had only minor atherosclerosis compared to purely cholesterol-fed rabbits. The in vivo production of thromboxane in oestrogen-treated rabbits decreased from 1641 +/- 162 pg mg-1 creatinine pretreatment to 808 +/- 92 pg mg-1 creatine at 12 weeks (P = 0.0001). In contrast, the in vivo production of prostacyclin increased during oestrogen treatment (P = 0.0027). The in vivo production of prostacyclin decreased during pure cholesterol feeding without oestrogen 1384 +/- 219 pg mg-1 creatinine to 702 +/- 142 pg mg-1 creatinine (P = 0.0091). The ratio of in vivo prostacyclin to thromboxane formation increased 2-3-fold during oestrogen therapy (P = 0.0007).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Medicine, Karolinska Institutet, Huddinge University Hospital, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Fogelberg
authors.forename: O
authors.initials: O
authors.lastname: Vesterqvist
authors.forename: U
authors.initials: U
authors.lastname: Diczfalusy
authors.forename: P
authors.initials: P
authors.lastname: Henriksson
mesh_terms: D000818:Animals; D001161:Arteriosclerosis / Q000209:etiology / Q000378:metabolism* / Q000517:prevention & control; D001808:Blood Vessels / Q000187:drug effects / Q000378:metabolism; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D011464:Epoprostenol / Q000096:biosynthesis*; D045166:Estradiol Congeners / Q000494:pharmacology*; D008297:Male; D011817:Rabbits; D013931:Thromboxanes / Q000096:biosynthesis*
chemical_list: D002791:Cholesterol, Dietary; D045166:Estradiol Congeners; D013931:Thromboxanes; D011464:Epoprostenol