THE IMMUNOHISTOCHEMICAL STUDY ON THE EXPRESSION OF TGF-beta2 IN THE MAXILLOFACIAL DEVELOPMENT OF A RAT EMBRYO

ABSTRACT

TGF-beta was identified as a homeodimeric peptide with a molecular mass f 25,000 D, and is a multifuntional peptide controls proliferation, differentiation, and other functions in many cell type, Many cells synthesize TGF-beta and essentially all them have specific receptors for this peptide. TGF-beta regulates of many other peptide growth factors and determines a positive or negative direction of their effects. At present there is relatively little information about the intrinsic physiologic role of TGF-beta n vivo. Experimental study was performed to observe the expreession of TGF-beta2 in the craniomaxillofacial devalopment of a rat embryo. Four male rats each weighting about 250g and twelve female rats each weighing about 200g were used, and induced to pregnancy. The embryos were serially sacrificed on the 13. 15. 18day after coitus. The embryos were serially sectioned by 4 micrometer and stained with H&E and immunohistochemical stain with TGF-beta2 and the histological examinations were carried out under the light microscope. After examination and comparision of specimens, the results of study were as follows : 1. In a 15, 18d emdryos, low grade strain of TGF-beta2 id found in the detal papillar of developing incisor, and around the Meckles cartilage and the other cartilage TGF-beta 2 is positive. In the formation of palate. TGF-beta is highly positive. 2. Ina devalopment of teeth in 15, 18d embryos, THG-beta2 is seen in the enameloblast derived from oral epithelium and the mesenchymal primordium of the plup. 3. In a epithelium of 13, 15, 18d emubryos, TGF-beta2 Is seen at a high levels. 4. In a 13, 15, 18d embryos, TGF-beta2 positivity of nasal cavity epithelium is related to the sensory organ epithelium. In a 15, 18d embryos, the lens of the eye derived from the surface embryonic ectoderm is TGF-beta2 positive. From above results, staining of TGF-beta is associated wiht tissues derived from neural crest mesenchyme and tissues of sensory organ derived from ectoderm. masked is also seen when remodeling of mesenchyme or mesoderm occurs, as during formation of palate and catilage.