Morphological observation on the subependymal layer of swine brain

자돈뇌실(仔豚腦室) 주위의 subependymal layer의 형태(形態)에 관한 관찰(觀察)

Normal swine brains at 1 to 70 days after birth were used to investigate the presence and morphology of the subependymal layer (SL) in the ventricle walls. The brain samples were taken from 27 pigs of 4 swine breeds. The results were summarized as follows: 1. SLs were observed on the walls of the lateral ventricle (LV) but none were observed on the walls of the 3th and 4th ventricles. 2. SLs of the LV walls were composed of mainly 3-to 10-cell layers in thickness. The thinest region of SLs was composed of only 1-to 2-cell thick on the dorsal and ventral walls, and the thickest region was composed of 250-to 300-cell thick on extension region of the SLs into the angle between the corpus callosum and caudate nucleus. 3. Of the LV parts observed, the SL thickness were 25-to 45-cell thick on the anterior horn, 3-to 10-cell thick on the body, 100-to 220-cell thick on the angle region between the corpus callosum and caudate nucleus, and 3-to 5-cell thick the superior walls of the posterior horn. Also the SL thickness was more thick on the anterior region than those on the posterior region. 4. SLs may be classified as three types by the cell distribution; one type of them is closely arranged cell region with the distinctive lateral margin from the periventricular white matter, the other type is loosely arranged cell region with the undistinctive lateral margin, and another type is two-subdivided region as the loosely and closely arranged cell layers in a layer. 5. SLs were extensively thick in young age but gradually decreased in size and cell number with age after 20-day age. SL layers were composed of mainly oligodendrocytes, astrocytes and immature cells of them. Morphological differences of SL in different breeds of pigs were not observed.