|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1990 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1989 : ¥1,200,000 (Direct Cost : ¥1,200,000)
The brush cell, also referred to as the tuft cell, is a rare cell type known to occur in the endoderm-derived epithelia of many mammalian species. In the present study, we found that an antibody against Liver-type Fatty Acid-Binding Protein (L-FABP) specifically immunostained the gastrointestinal brush cells of the rat, and utilized this immunoreactivity as a specific marker of the brush cell to elucidate its previously unclarified aspects.
The largest populations of brush cells were found in the stomach and common bile duct. In the stomach, brush cells were present in a group in the groove of cardiac region as well as scattered singly in the surface and foveolar epithelia of the fundic and pyloric regions, with intense immunoreactivity for L-FABP. Morphologically, it was clarified that all brush cells had a thin basal cytoplasmic process without secretory granules. In the ontogeny of rats, brush cells first occurred in the new born stomach, with immunoreactivity for L-FABP, and increas
ed remarkably in number within the few weeks following the end of the first 2 weeks of sackling period.
In the common bile duct, The brush cells as recognized by scanning electron microscopy first appeared in the epithelium at 4 weeks after birth. They showed a remarkable increase in number between 8 and 16 weeks and finally occupied about 30 % of the total epithelial cell population of common bile duct. The initial development of brush cells in the females delayed for approximately 2 weeks from that of males. On the other hand, the L-FABP-immunoreactive brush cells first appeared only after 8 weeks postpartum. They showed a gradual increase in number after 16 weeks but reached only about 25 % of the total brush cell population by the time of 40 weeks.
The present study, by virtue of the specific histochemical marker, provided new findings concerning the distribution, morphology and ontogeny of the brush cell. Also, the expression of L-FABP in the brush cell may shed light on the functional aspect of this cell type in relation to the fatty acid meTabolism. Less