Uterine vein and maternal urinary levels of activin A and inhibin A in pre-eclampsia patients.
OBJECTIVE
The aims of this study were to investigate if (i) urinary concentrations of activin A and inhibin A are altered in pre-eclampsia (PE) and (ii) to study the relationship between uterine vein and peripheral vein concentrations of these hormones in PE patients.


METHODS
In a retrospective study, maternal peripheral vein and uterine vein serum and maternal urine samples collected at the time of delivery were analysed. There were three groups of patients; (i) group 1: term normal pregnancies (n = 19) (ii) group 2: patients who developed PE < or = 37 weeks (n = 17) and (iii) group 3: patients who developed PE 37-40 weeks (n = 8). Serum and urinary activin A, follistatin, inhibin A and pro alpha C and urinary creatinine levels were measured using enzyme immunoassays in the laboratory.


RESULTS
Normal pregnant urine samples had very low levels of activin A and inhibin A. Both groups 2 and 3 PE patients had significantly higher levels of inhibin A (P < 0.001) and activin A (P < 0.001) compared to the controls. Pro-alpha C was not altered and follistatin was below the detection limit of the assay in the urine. Maternal peripheral serum activin A and inhibin A were significantly higher in groups 2 (P < 0.001) and 3 (P < 0.05) patients compared to the controls. Pro-alpha C-containing inhibins were higher in group 2 patients (P < 0.05) compared to the controls in the peripheral circulation. Uterine vein serum activin A and inhibin A levels were also significantly higher in groups 2 (P < 0.001) and 3 (P < 0.05) patients compared to the controls. There was a highly significant positive correlation between peripheral and uterine vein serum concentrations of activin A, follistatin, inhibin A and pro alpha C, suggesting the same source for these proteins in PE.


CONCLUSIONS
Urinary activin A and inhibin A are raised in groups 2 and 3 PE patients. The magnitude of rise (> 25-fold) suggests these proteins may rise in patients before the onset of the clinical symptoms of PE. Uterine vein levels of these proteins are also raised in PE.
Muttukrishna
S
S
Department of Obstetrics and Gynaecology, Royal Free University College Medical School, London, UK. s.muttukrishna@ucl.ac.uk
Hyett
J
J
Paine
M
M
Moodley
J
J
Groome
N
N
Rodeck
C
C
D028341:Activins / Q000097:blood / Q000652:urine; D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D002406:Catheterization, Peripheral; D005260:Female; D038681:Follistatin / Q000032:analysis / Q000097:blood / Q000652:urine; D006801:Humans; D028322:Inhibin-beta Subunits / Q000097:blood / Q000652:urine; D007265:Inhibins / Q000032:analysis / Q000097:blood / Q000652:urine; D021041:Placental Circulation; D011225:Pre-Eclampsia / Q000097:blood / Q000652:urine; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011498:Protein Precursors / Q000032:analysis / Q000097:blood / Q000652:urine; D012189:Retrospective Studies; D014599:Uterus / Q000098:blood supply; D014680:Veins
D038681:Follistatin; D011498:Protein Precursors; C422405:activin A; C422362:inhibin A; C095971:inhibin-alpha subunit precursor; D028341:Activins; D007265:Inhibins; D028322:Inhibin-beta Subunits