ABSTRACT
The ultrastructural localization of alkaline phosphatase and K+-NPPase was investigated in brain capillaries of newt by a cytochemical study using whole brain perfusion. The alkaline phosphatase activity was present in both luminal and antiluminal membranes of the endothelial cells. By contrast, the K+-NPPase was located only in antiluminal membranes of the brain capillaries. This distinct enzymatic distribution suggested that the luminal and antiluminal membranes are functionally different. The role of alkaline phosphatase and K+-NPPase in the blood brain barrier is discussed.
Subject(s)
4-Nitrophenylphosphatase/analysis , Alkaline Phosphatase/analysis , Capillaries/enzymology , Cerebrovascular Circulation , Ouabain/pharmacology , Phosphoric Monoester Hydrolases/analysis , Animals , Brain/ultrastructure , Capillaries/ultrastructure , Histocytochemistry , Microscopy, Electron , Salamandridae , Sodium-Potassium-Exchanging ATPase/analysisSubject(s)
Asthenia/drug therapy , Gangliosides/therapeutic use , Restless Legs Syndrome/drug therapy , Adult , Aged , Asthenia/etiology , Female , Humans , Male , Middle Aged , Nervous System Diseases/drug therapy , Nervous System Diseases/etiology , Restless Legs Syndrome/etiology , Sensation , Uremia/complicationsABSTRACT
The permeability of cerebral vessels to exogenous peroxidase was studied in the newt. The reaction product was found only inside the cerebral or pial blood vessels. Electron microscope investigations revealed the presence of reaction product along the luminal area of vessels and in some parts of the intercellular spaces at the level of tight junctions joining endothelial cells. On the basis of the ultrastructural peroxidase localization, the presence of a brain-blood barrier in Triturus is discussed.
