Mast cells, histamine and development of the placental vascular network in pregnancies complicated by preeclampsia and intrauterine growth retardation

Importance of angiogenesis in proper development of placenta is unquestioned. Abnormalities in vascular development are typical for complications of pregnancy: intrauterine growth retardation (IUGR) and preeclampsia (PE). As mast cells are involved in new vessels sprouting and development we tried to disclose if they can be involved in etiology or pathogenesis of IUGR and/or PE. MATERIAL AND METHODS: Placentas from PE-complicated pregnancies (n=11), IUGR-complicated pregnancies (n=10), and from healthy women--controls (n=13) were obtained after cesarean sections. Histamine concentration was measured and immunohistochemical staining for mast cell tryptase was performed. Microscopic slides of placental tissue were analyzed with morphometric software. RESULTS: We disclosed increased histamine concentration in PE group--227.3 +/- 17.7 (in ng of histamine per 1 g of tissue) and decreased concentration in IUGR group 114.3 +/- 13.5 vs control--178.1+/- 18.9. Histamine concentration corresponded with density of mast cells in examined groups: PE group--8.32 cells/mm2 +/- 1.3, IUGR--3.07 +/- 1.05 and control--5.14 +/- 1.2. The mean area of mast cells identified in PE as well as in IUGR group was smaller than the mean area of mast cells in controls. V/EVT index was decreased in PE and IUGR group in comparison to controls, respectively: 0.15 +/- 0.018; 0.12 +/- 0.014; 0.23 +/- 0.029. CONCLUSIONS: We suggest that differences in mast cells density and corresponding differences in histamine concentration are associated with pathogenesis of PE and IUGR or are consequence of primary cause.