The role of cerebral microvessel endothelium in regulation of cerebral blood flow through production of endothelin-1.
We have previously reported the production of endothelin-1 (ET-1) by the cerebral microvessel endothelia and suggested an important role of ET-1 and microvessel endothelia in the regulation of local blood flow within the brain. In the present study, radioimmunoassay of ET-1 revealed that ET-1, produced by cultured cerebral microvessel endothelia grown on a filter, is released mainly to the basal side (corresponding to the basement membrane side), not to the apical side (corresponding to the vascular lumen side). This might indicate that ET-1 constricts arterioles locally at the same place where it is produced by endothelia. The present results also show that cultured cerebral microvessel endothelia produce less ET-1 under low oxygen pressure and that they produce more ET-1 under low carbon dioxide pressure. Taken together, our results may suggest that the negative feedback regulation of cerebral blood flow through oxygen and carbon dioxide pressure is mediated by ET-1 produced locally by cerebral microvessel endothelia.
Yoshimoto
S
S
Department of Neurosurgery, Faculty of Medicine, University of Tokyo, Japan.
Ishizaki
Y
Y
Mori
A
A
Sasaki
T
T
Takakura
K
K
Murota
S
S
D002196:Capillaries / Q000378:metabolism / Q000502:physiology*; D002245:Carbon Dioxide / Q000494:pharmacology; D002478:Cells, Cultured; D002560:Cerebrovascular Circulation / Q000502:physiology*; D016232:Endothelins / Q000502:physiology*; D004730:Endothelium, Vascular / Q000378:metabolism / Q000502:physiology*; D010100:Oxygen / Q000494:pharmacology; D011863:Radioimmunoassay
D016232:Endothelins; D002245:Carbon Dioxide; D010100:Oxygen