Abstract: BACKGROUND ＆ AIM: To investigate the relationship among the endothelin－1(ET-1) content, microvessel density, the grading and prognosis of astrocytomas. MATERIAL AND METHODS: Seventy-four cases of astrocytoma with definite follow-up data who underwent surgical treatment in recent 8 years in our hospital were collected. Image cytometry(ICM), and Immunohistochemistry Streptavidin-Peroxidase method were carried out to study the microvessel density(MVD), the positive expression rates of ET-1 and ET-1 content. The incidence of the MVD, the positive rates of ET-1, ET-1 content, survival time and grading were evaluated with correlation analysis. RESULTS: ① The results showed that the positive rates of ET-1 and ET-1 content were both significantly different between normal astrocyte and astrocytomas, and high grade(Ⅳ-Ⅲ)astrocytomas and low grade(Ⅱ-Ⅰ) astrocytomas. But there was no significant difference between grade Ⅰand grade Ⅱ.② The results showed that MVD in high grade astrocytomas was much higher than that in low grade astrocytomas, and the survival time was significantly different among each grade (P<0.05). ③ The correlativity of the grading, ET-1 content, MVD and the survivial time show that ET-1 content have positive correlation with the grading, and MVD,but negative correlation with survival time of astrocytoma. CONCLUSION: ①It is suggested that ET-1 may act on the growth and angiogenesis of astrocytoma. ② It is suggested that ET-1 content,and MVD may be an useful method for diagnosis, grading,prognosis of astrocytoma.

Key words: astrocytoma, endothelin-1, immunohistochemistry, prognosis, microvessel