[Hyperestrogenemia following various shunt operations: on the role of estrogens in the development of focal nodular hyperplasia of the liver].
Hormones especially estrogens have been suspected to induce liver cell tumours or hepatic focal nodular hyperplasia (FNH). In rats 6 months after portocaval anastomosis (PCA) the occurrence of FNH has been observed. Modified portocaval anastomosis (mPCA) does not lead to FNH. To test the concept of estrogen induced tumour formation we measured in both groups as well as in a shamoperated control group (SOP) the levels of estradiol (E2), estrone (E1) and of testosterone (T). In a further experiment the hormone levels were measured in rats with portocaval transposition (PCT), an operation which leads to high gonadal hormone production. In groups of 6 male rats each (280-300 g) either SOP, PCA, mPCA or PCT were performed. 30 days later the blood levels of E2, E1, and of T were measured by radioimmunoassay. In PCT-rats hormone levels were measured in the blood synchronously taken from the inferior vena cava (prehepatic) and from the heart (posthepatic), to get an information of the hepatic hormone degradation. After PCA the median level of E2 (77 pg/ml) and E1 (63 pg/ml) are significantly elevated when compared with SOP-rats (41 and 43 pg/ml). Equally after mPCA the E2 and E1 levels are significantly higher (61 and 70 pg/ml) than in controls rats. In contrast the concentrations of T are significantly reduced (PCA 0.03, mPCA 0, 10, SOP 1.0 ng/ml). PCA as well as mPCA result in a hyperestrogenic and hypoandrogenic status. When PCA and mPCA are compared, only the testosterone blood levels are significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)