STUDY DESIGN: In vitro studies using human intervertebral disc for the localization of the type IV collagen. OBJECTIVE: 1) To study the distribution pattern and immunoexpression of type 4 collagen in the intervertebral disc, 2) To study the function of type IV collagen in the intervertebral disc. SUMMARY OF BACK GROUND: The correlations of degeneration changes and collagens in the dics have not been determined. The reports for type IV collagen were few. So far, the histologic analysis for the expression of type IV collagen in the intervertebral disc has not been done. There was no report to study the function of the type IV collagen in the intervertebral disc. METHODS: Fifty-four disc blocks obtained during anterior interbody fusion of the lumbar spine were used to observe the expression pattern of the type IV collagen with immunochemical stain. For the observation of the myxomatous degeneration in the intervertebral disc, the alcian blue stain with periodic acid-schilff was done. For the control group, 22 neonate intervertebral disc blocks were obtained at autopsy. RESULTS: The immunoreactions for type IV collagen were associated blood vessels in the anulus fibrosus in the disc. There was no statistical significant difference of the type IV collagen expression between the control and disease groups. Myxomatous degenerations were observed as the irregular form in the degenerative intervertebral disc. CONCLUSION: The immunoreactions for the type IV collagen were observed in the intervertebral discs and associated with the formation of the blood vessels, especially in anulus fibrosus.