Naoki Hashimoto

Effects of portacaval shunt, transposition, and dimethylnitrosamine-induced chronic liver injury on pancreatic hormones and amino acids in dog

The effect of portacaval shunt on amino acid metabolism and pancreatic hormone secretion remains a subject of controversy. This might be due to the fact that shunt has two consequences; it shunts portal blood into the systemic circulation, and it causes hepatic parenchyma dysfunction by decreasing total hepatic blood flow. In order to see which one of these two is the more important factor, we created a model of portacaval transposition in dogs (PCT) causing portal systemic shunting without impairing hepatic blood flow and compared it with a model of hepatic dysfunction in dogs created by administering dimethylnitrosamine (DMNA). The dynamics of amino acid levels and pancreatic hormone secretion in the portal blood were investigated. DMNA dogs and dogs with a standard end-to-side portacaval shunt (Eck) showed elevated immunoreactive glucagon (IRG) levels and low immunoreactive insulin (IRI) levels in the portal blood as well as an amino acid imbalance, while values in PCT dogs were similar to those of controls. These data suggested that high IRG and low IRI in the portal blood and amino acid disturbances in the dogs with Eck shunts were due to hepatic parenchyma dysfunction, rather than to portal-systemic shunting.

Hepatobiliary and gastrointestinal imaging after pancreaticoduodenectomy —A comparative study on Billroth I and Billroth II reconstructions

This study was conducted to compare the passage of bile and food through the remnant alimentary tract between 2 and 6 months following pancreaticoduodenectomy in patients undergoing Billroth I (Imanaga) and Billroth II (Child) reconstructions, using dual scintigraphy. In the patients who underwent Childs operation (n=14), hepatobiliary scintigraphy showed a prominent stasis of bile tracer in the proximal jejunal loop and a significant time delay before the bile and food became mixed at the upper jejunum. On the other hand, in the patients who underwent Imanagas operation (n=9) no bile stasis in the proximal jejunal loop was found and the time taken before the two agents became mixed was similar to that of healthy controls (n=7). The time taken for the two agents to mix at the upper jejunum was 65.8±7.9 min in the patients after Childs operation, 17.3±2.5 min in those after Imanagas operation, and 18.5±2.8 min in the healthy controls, respectively. Continuous stasis of bile in the proximal loop and severe postcibal asynchronism in patients who undergo Childs operation can therefore cause reflux cholangitis and absorptive disturbances in the long postoperative term. The results of this study suggest that Imanagas reconstruction is a more physiological procedure than Childs reconstruction following pancreaticoduodenectomy.

A comparison of the metabolic changes after the distal splenocaval and portacaval shunts.

The distal splenorenal shunt (DSRS) is the recommended procedure for selective variceal decompression, but its use may be limited in patients who have undergone left nephrectomy, those with an anatomically aberrant relationship between the splenic and left renal veins, and those whose preoperative angiographic findings suggest a risk of developing postoperative renal vein hypertension. For these clinical situations, the selective distal splenocaval shunt (DSCS) is a useful alternative to the DSRS. However, the metabolic consequences of the DSCS have not yet been studied in detail and therefore, using a canine model, the metabolic changes following the DSCS and the portacaval shunt (Eck) were compared. The metabolic changes observed following the Eck were hyperammonia and amino acid imbalance, while those following the DSCS were similar to those of the control dogs. In terms of the hepatic adenosine triphosphate level, which reflects hepatic mitochondrial function, the DSCS dogs were also similar to the control dogs. These data suggest that there was no metabolic disadvantage of the DSCS compared to the control.

The significance of autoantibody against calmodulin in chronic liver diseases, collagen diseases and malignant neoplasmas.

慢性肝疾患,膠原病,悪性腫瘍における仔牛より精製したカルモデュリン(CaM)に対する自己抗体の出現を報告した.抗CaM抗体の測定は酵素抗体法によった.抗体陽性血清と,CaM結合アガロースとを反応させ,酸性グリシンによる溶出分画中に,抗CaM抗体活性を認めた.抗体活性は,アクチン,仔牛胸腺DNAによる吸収では,低下しなかったが,CaM,家兎肝細胞膜分画および肝ホモジュネート77,000g上清分画による吸収で,低下した.IgGクラスの抗体は,肝疾患51.2%,膠原病25.2%,悪性腫瘍41.2%に認め,正常人(0%)より高頻度であった.IgMクラスの抗体は,それぞれ36.9%, 3.9%, 0%, 5%で,肝疾患,特に肝硬変は高頻度であった(p<0.02). IgAクラスの抗体は,肝疾患(28.9%),膠原病(15.5%)で,正常者(4.3%)より高頻度であった.抗平滑筋抗体の出現とは相関しなかった.

An autopsy case of distal splenorenal shunt with splenopancreatic disconnection.

選択的shunt術である遠位脾腎静脈吻合術におけるshuntの選択性喪失の主要因としては,shunt脾静脈への遠肝性側副血行路-特に膵内および膵周囲を通る-発達といえ,本術式の改良(shunt脾静脈の膵からの完全遊離)がshuntの選択性の術後長期間の保持に有効であると考えられた.そこで改良術式を行い術後3年8カ月目に肝不全で死亡した症例(55歳男,肝硬変)の剖検時門脈造影よりshuntの選択性維持に関しての検討を行った.脾静脈近位端よりのshmt脾静脈への細い数本の側副血行路を認めたのみで,門脈循環異常といえる病態は認めず,術式の改良は十分効果的といえた.ただshunt脾静脈への下腸間膜静脈からの側副血行路を認め,高圧のportamesenteric systemの腹腔内では低圧のshunt脾静脈の完全な分離は遠位脾腎静脈吻合術の術式改良を行っても不可能と考えられた.