Objective      To determine the renal function and pathological changes after intravenous injection of syncytiotrophoblast microparticles (STBMs) in pregnant mice.       Methods      When the mice were pregnant for 18 d

the placentas were taken to prepare STBMs. The morphology of STBMs was observed by transmission electron microscopy

and the protein level of STBMs was detected with BCA Protein Assay Kit. Fluorescence-labeled STBMs were injected into the pregnant mice via the tail veins

and the in vivo distribution of STBMs were traced. The pregnant mice were divided into STBM group

control group and PBS group. The STBM group was treated by tail vein injection of STBMs (0.2 mL) with protein concentration of 0.15 mg/mL from the 8th day of the pregnancy. When the pregnancy lasted for 18 d

24-h urine of the mice was collected to detect microalbuminuria (M-TP)

urine creatinine (U-Crea)

urinary protein creatinine ratio (M-TP/Cr)

24-h urine protein (24 h U-TP) and uric acid (U-Uric). Meanwhile

the blood was sampled to detect urea nitrogen (BUN)

creatinine (Scr) and cystatin C (Cys-C)

and the kidney specimens were treated by hematoxylin-eosin (HE) staining to observe renal pathological changes.       Results      The urine M-TP

M-TP/Cr

and 24 h U-TP of the STBM group were significantly higher than those of the control group and the PBS group (P0.01). There was no significant difference in U-Uric between the control group and the PBS group (P0.05)

but the U-Uric level was significantly decreased in the STBM group (P0.01). The serum BUN

Scr

and Cys-C were significantly increased in the STBM group (P0.01). The HE staining results showed glomerular endothelial cell proliferation

swelling

deformity

and renal tubular cloudy degeneration in the STBM group.       Conclusion      STBM raising can cause renal damage in the pregnant mice

so STBM may play an important role in the renal damage of preeclampsia.