The localization of dopamine D2 receptor mRNA in the human placenta and the anti-angiogenic effect of apomorphine in the chorioallantoic membrane.
While there are some reports indicating that dopamine (DA) and D2-like receptors (Rc) are detected in human placenta, there is little evidence available regarding the function of DA or the precise localization of its receptors in this organ. In the present study, we confirmed the placental expression of DA D2 Rc transcripts by Northern blot analysis. Using in situ hybridization, we also first revealed that DA D2 Rc mRNA was expressed in cytotrophoblasts, syncytial trophoblasts, vascular endothelial cells, Hafbauer cells, and fibroblasts in the chorionic villi of the human placenta. The expression sites of DA D2 Rc mRNA led us to suspect other functions of DA in the placenta besides the regulation of human placental lactogen. Since the cells expressing DA D2 Rc mRNA are related to proliferation and remodeling of placental tissue, we tried to evaluate a possible involvement of DA in the regulation of placental angiogenesis. To this end, we used the chicken chorioallantoic membrane (CAM) assay. In CAM assay, apomorphine, a potent nonselective agonist of DA, has an anti-angiogenic effect. These results suggest that DA may regulate the vascularization of human placenta through its receptors present in the chorionic villi.
Kim
H J
HJ
Department of Anatomy, College of Medicine, Gyeongsang National University, Chinju, Korea.
Koh
P O
PO
Kang
S S
SS
Paik
W Y
WY
Choi
W S
WS
D000482:Allantois / Q000098:blood supply* / Q000187:drug effects; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D015152:Blotting, Northern; D002642:Chick Embryo; D002823:Chorion / Q000098:blood supply* / Q000187:drug effects; D004298:Dopamine / Q000502:physiology; D018491:Dopamine Agonists / Q000494:pharmacology*; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D010920:Placenta / Q000098:blood supply / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000096:biosynthesis* / Q000235:genetics
D018491:Dopamine Agonists; D012333:RNA, Messenger; D017448:Receptors, Dopamine D2; D001058:Apomorphine; D004298:Dopamine