مطالعه ايمونوهيستوشيميايي بيان كلاژن نوع 4 در خلال شكل گيري عدسي

Immunohistochemical Study of Type IV Collagen during Lense Development

BACKGROUND AND OBJECTIVE: Extracellular matrix (ECM) and basement membrane (BM) play important roles in many developmental processes during development and after birth. Among the components of the BM, collagen fibers especially type IV is the most important part of BM. The aim of this study was to determine expression of collagen type IV in the BM of lens structure during embryonic mouse development. METHODS: In this experimental study, 22 female Balb/C mice were selected randomly and were kept under normal condition, finding vaginal plug was assumed as day zero of pregnancy. From embryonic day 10 to 20, all specimens were sacrificed by cervical dislocation and their head embryos were fixed, serially sectioned and it was also done after birth in 10-20 day neonates. Immunohistochemistry study for tracing of collagen type IV in eye capsule region was carried out. Grading served according to the firth method. FINDINGS: Primary lens was visible in anterior pole of optic cup as an undifferentiated cellular mass on day 11 of gestation. Collagen IV immunostaining appeared at the early stage of embryonic day 12 in BM of anterior epithelial and gradually increased until day 17 in ECM and posterior pole. After this period, severe reaction staining collagen IV was not changed in any part of the lens. CONCLUSION: Our results indicated high levels of collagen IV is present at the BM of anterior epithelial lens during early development (E-12) and increases in anterior and posterior epithelial capsule (E-15 to E-17) days. These findings establish the importance of collagen IV during critical period of developing lens.