RESUMO
In 80 Wistar rats were investigated the prolonged action of Angiotensin II in a dosage of 0,05 mg/kg/die ip. appl. on microstructures of the sensomotoric cortex. It is observed, after the first application, a biphasic reaction of brain vessels, in the beginning a pronounced vasodilatation (5 min p.-inject) which 10 min later turn into a vasoconstriction. In correlation with the applications frequency the repeated injection of the octapeptide leads to perivascular edemas. Neurons of the sensomotoric cortex show strong swellings, which later turn in to involutions. Pronounced destructions of mitochondria are demonstrable. Conceivable mechanisms were discussed.
Assuntos
Angiotensina II/farmacologia , Edema Encefálico/induzido quimicamente , Córtex Cerebral/efeitos dos fármacos , Hidrocefalia/induzido quimicamente , Animais , Permeabilidade Capilar/efeitos dos fármacos , Masculino , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Ratos , Córtex Somatossensorial/efeitos dos fármacosRESUMO
In 80 wistar rats were investigated the prolonged action of Angiotensin II in a dosage of 0,05 mg/kg/die ip. appl. on macrostructures of brain. We tested the material 1-, 3-, 7-, 14- and 21 days after the first application. In correlation with duration of the Angiotensin II action a hydroencephalie was produced. This was marked by a lumen, so big as a 1/4-1/5 of the whole brain extent. Further we observed a considerable atrophy of brain structures, particularly in the corpus callosum and the white and gray Substance of cortex. Light-microscopically we would prove edemas perivasculary with separations of ependymal cells. Conceivable mechanisms were discussed.