[Expression of netrin-1 in placenta from patients with pre-eclampsia and the relation to placental angiogenesis]

To investigate the expression of netrin-1 in placenta from patients with pre-eclampsia and the relation to placental angiogenesis.

Twenty patients with pre-eclampsia (12 mild cases and 8 severe cases) and 20 normal late pregnant women were investigated. The expression of netrin-1 mRNA and protein was determined with RT-PCR and Western blotting respectively. The placenta vascular density was examined by immunohistochemical F8 staining.

(1) The values of netrin-1 mRNA in normal group and pre-eclampsia groups were 0.51 +/- 0.08 and 0.41 +/- 0.06; The values of netrin-1 protein in normal group and pre-eclampsia groups were 26.4 +/- 1.8 and 20.5 +/- 1.3 (P < 0.01). The values of netrin-1 mRNA in mild and severe pre-eclampsia groups were 0.48 +/- 0.08 and 0.34 +/- 0.07; The values of netrin-1 protein in mild and severe pre-eclampsia groups were 22.8 +/- 1.3 and 18.2 +/- 1.0 (P < 0.01). (2) The placenta vascular density in pre-eclampsia (54 +/- 8) was significantly reduced than in normal group (65 +/- 10) (P < 0.01); the decrease was even more obvious in severe group (48 +/- 7) than in mild group (60 +/- 9) (P < 0.01). (3) There was positive correlation between the expression of netrin-1 mRNA and protein and placenta vascular density in normal pregnancy (r = 0.67 and 0.71, P < 0.01), as well as in pre-eclampsia group (r = 0.61 and 0.70, P < 0.01), in mild pre-eclampsia group (r = 0.69 and 0.73, P < 0.01), and in severe pre-eclampsia group (r = 0.71 and 0.75, P < 0.01).

The study shows that the decrease of netrin-1 in placenta of patients with pre-eclampsia is one of the possible reasons for the reduction of placenta vascular density.