Changes caused by hydrocephalus, induced by kaolin, in the corpus callosum of adult dogs.
OBJECTIVE
To analyze the ventricular enlargement and myelination of the corpus callosum in adult dogs after four and eight weeks of kaolin-induction of hydrocephalus.


METHODS
36 dogs were randomly divided into 3 groups: 1 - without hydrocephalus, 2 - kaolin-induction of hydrocephalus until the fourth week, and 3 - kaolin-induction of hydrocephalus until the eighth week. Ventricular ratios and volumes were calculated using magnetic resonance images, and myelination of the corpus callosum were histologically evaluated using solocromo-cianin stain.


RESULTS
Radiological hydrocephalus was observed in 93.75% and overall mortality was 38.4%. Ventricular volumes and ratios were higher in groups 2 and 3 compared to group 1 and similar when measures in the fourth and eighth weeks were compared in the group 3. Indices of luminescence in the knee and in the splenium of the corpus callosum were higher in group 2 than in group 1 indicating that there was loss of myelin in group 2, and similar in groups 1 and 3, showing a tendency to remyelination after 8 weeks.


CONCLUSIONS
The corpus callosum of dogs with kaolin-induced hydrocephalus responds with demyelination of the knee and splenium by the fourth week with a tendency to remyelination by the eighth week.
Department of Surgery and Anatomy, FMRP, USP, Ribeirao Preto, Sao Paulo, Brazil. ejrcardoso@uol.com.br
Edvaldo José Rodrigues
EJ
Cardoso
João José
JJ
Lachat
Luiza Silva
LS
Lopes
Antonio Carlos dos
AC
Santos
Benedicto Oscar
BO
Colli
D000538:Aluminum Silicates; D000818:Animals; D002552:Cerebral Ventricles / Q000473:pathology / Q000503:physiopathology*; D003337:Corpus Callosum / Q000473:pathology / Q000503:physiopathology*; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006849:Hydrocephalus / Q000139:chemically induced / Q000503:physiopathology*; D007616:Kaolin; D008279:Magnetic Resonance Imaging; D008297:Male; D009186:Myelin Sheath / Q000502:physiology; D009929:Organ Size; D011897:Random Allocation; D015203:Reproducibility of Results; D013997:Time Factors
D000538:Aluminum Silicates; D007616:Kaolin