Expression of angiogenic factors in placenta of stressed rats.
The aim of the present study was to analyse the influence of stress on pregnant rats, particularly in terms of maternal, placental and fetal weight, placental morphology and placental gene expression of the angiogenic factors Vegfa and Pgf and their receptors. The parameters were evaluated on gestation Day 20. Maternal, fetal and placental weights were statistically lower in stressed animals than controls, suggesting abnormalities in gestational physiology. Morphologically the placentas of rats subjected to stress were reduced in size and weight, with few glycogen cells and a significant increase in the number of apoptotic cells. Stress caused an increase in placental gene expression of Vegfa (P<0.05) and a reduction in Pgf, Flt1 and Kdr expression (P<0.05). It has been suggested that increased VEGF is associated with vasodilatation and hypotension, but in this model persistent hypertension was present. This study suggests that the limited hypotensive Vegfa response to stress-induced hypertension could result from reduced expression of Flt1/Kdr disrupting specific VEGF pathways. These findings may elucidate one of the multiple possible factors underlying how stress modulates placental physiology, and could aid the understanding of stress-induced gestational disorders.
Department of Obstetrics and Gynecology, Faculty of Medicine, University of São Paulo, São Paulo, Brazil.
Isis Paloppi
IP
Corrêa
Rodrigo
R
Ruano
Nilton Hideto
NH
Takiuti
Rossana Pulcinelli Vieira
RP
Francisco
Estela
E
Bevilacqua
Marcelo
M
Zugaib
D042501:Angiogenic Proteins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis; D005260:Female; D005786:Gene Expression Regulation; D005865:Gestational Age; D046110:Hypertension, Pregnancy-Induced / Q000209:etiology / Q000378:metabolism; D009929:Organ Size; D010920:Placenta / Q000378:metabolism* / Q000473:pathology; D000072483:Placenta Growth Factor; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000150:complications* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism
D042501:Angiogenic Proteins; C000608038:Pgf protein, rat; D011257:Pregnancy Proteins; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; C467498:vascular endothelial growth factor A, rat; D000072483:Placenta Growth Factor; C501164:Flt1 protein, rat; D040281:Vascular Endothelial Growth Factor Receptor-1; D040301:Vascular Endothelial Growth Factor Receptor-2