Perfil epidemiológico do traumatismo crânio-encefálico no Distrito Federal em 1991 / Epidemiological profile of craniocerebral injuries in the Federal District en 1991

ABSTRACT

Hydrocephalus-induced changes in intracranial pressure (ICP), ventricular size, periventricular edema and erythrocyte density (ED), median eminence thickness, and pituitary gland morphology were determined in adult female hamsters (Mesocricetus auratus). Hydrocephalus (HC) was induced by intracisternal injection of kaolin (0.03 ml, 50 mg/ml saline); controls did not receive kaolin. Animals were chronically cannulated and ICP measured periodically (Camino V 420). At selected times control and treated animals were decapitated, brains removed with the pituitary gland attached and fixed by immersion in formalin. Coronal brain slices containing the paraventricular nuclei (PVN), supraoptic nuclei (SON), suprachiasmatic nuclei (SCN), subfornical organ (SFO) and median eminence (ME) were prepared using a rodent brain matrix slicer and ventricular area was quantitated by morphometric analysis (Jandel Video Analysis System). Samples were collected from the cortex and periventricular white matter (containing the PVN, SON, and SCN) and the median eminence. The whole pituitary gland was also collected for determination of specific gravity by linear density column method. Erythrocyte Density was assessed by immersing hydrocephalic brain slices containing the selected nuclei in Karnovisky's fixative on day 9 post HC induction, and in situ erythrocytes stained for endogenous peroxidase by tetramethyl benzidine cytochemistry to facilitate visualization. Previous studies in our laboratory have established that HC can result in alterations in estrous cycle, water balance, food intake and growth. The result in part from decrease perfusion of the endocrine hypothalamus and pituitary gland, edema and pressure-induced changes in the median eminence structures.