Cast-model and scanning electron microscopy of the rat brain ventricular system.

In order to establish a good experimental model for comparative studies of the brain ventricular system in mammals, a resin-cast model and scanning electron microscopy were employed to examine the rat brain ventricular system. From the resin-cast model, we found that the gross morphology of the brain ventricular systems of rats is simpler than that of humans. From scanning electron microscopy, local variations of ependymal cells lining the rat brain ventricle were noted. Most areas of the ventricles were lined by ciliated ependymal cells arranged in regular rows, whereas in some other areas non-ciliated ependymal cells were also observed. Epiplexus cells and supraependymal cells were also encountered on the top surface of the choroid epithelium, and ependymal cells in certain area such as the pineal recess.