[Association of transforming growth factor-β1 with pathological grading of intervertebral disc degeneration].
To explore the role of transforming growth factor-β1 (TGF-β1) in intervertebral disc degeneration and its association with the pathological grading of disc degeneration. Normal and degenerative intervertebral disc tissues were collected were classified into 5 grades of increasing degenerative changes. HE staining, immunohistochemistry, TUNEL staining and RT-PCR were used to detect the expression of TGF-β1 in the disc tissues. Immunohistochemistry and RT-PCR showed positive expressions of TGF-β1 and Bcl-2 in normal disc tissues, where Bax was expressed at have a trace level. In the degenerative disc tissues, TGF-β1 expression increased with the pathological grades; the expression levels of TGF-β1 showed significant differences between degenerative and normal tissues and between grade IV and grade I disc tissues (P<0.01). TGF-β1 is an important factor participating in the disc degeneration and its expression level is closely related to the pathological grade of degenerative discs.