Chao-Tien Hsu

The effect of chemical sympathectomy on acute liver injury induced by carbon tetrachloride in spontaneously hypertensive rats

The effects of 6-hydroxydopamine (6-OHDA) on carbon tetrachloride (CCl4)-induced acute liver injury were examined in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY). Plasma glutamate-pyruvate transaminase (GPT) activity was increased in both strains after one dose of CCl4 administration, although the increase was more significant in SHR than in WKY. Pretreatment with 6-OHDA inhibited the increase in GPT activity after CCl4 administration in both strains and especially in SHR. 6-OHDA also reduced the noradrenaline (NA) content of the liver and increased the hepatic blood flow in both strains. It caused a greater decrease in blood pressure in SHR than in WKY. The results suggest that 6-OHDA blocks the sympathetic neural activity in the liver, resulting in vasodilatation and increase in hepatic blood flow and thereby alleviating the circulatory disturbance produced by CCl4 preventing acute liver damage, especially in SHR.

Osteoclast-like giant cell tumour of the gallbladder

We describe a rare carcinoma of the gallbladder containing osteoclast-like giant cells. Well-differentiated adenocarcinoma was found in the mucosa of the fundus, and osteoclast-like giant cells were present mainly in a haemorrhagic mass protruding from the mucosal surface. The metastatic hepatic tumour was composed chiefly, if not exclusively, of osteoclastoma-like cells, but minute carcinomatous elements were also present. There was an apparent transition between the giant cells and tubular structures in both the gallbladder tumour and hepatic tumour. However, ultrastructural study did not reveal any evidence of epithelial differentiation in the giant cells. Immunohistochemical studies suggested that the mononuclear and giant cells were mesenchymal and histiocytic in nature (vimentin and factor XIII a positive). A few exceptional giant cells transforming from the fine tubular structure were positive for epithelial membrane antigen. In conclusion, the osteoclast-like giant cell tumour component was thought to represent mesenchymal metaplasia in pre-existent adenocarcinoma.

Early gastric cancer arising from localized Ménétrier’s disease

SummaryA case of early gastric cancer arising from Ménétrier’s disease in the stomach is described. The patient was a 53-year-old man, who suffered from epigastralgia. Radiological and endoscopic examination demonstrated giant mucosal folds along the greater curvature of the stomach. On the distal margin, signetring cell carcinoma was demonstrated by biopsy. The coexistence of Ménétrier’s disease and early gastric cancer has rarely been reported. Cases reported in the literature were reviewed and the increased malignant potential of Ménétrier’s disease was discussed.

Expression of Tie-2 and angiopoietin-1 and -2 in early phase of ulcer healing

Background. Angiogenesis is an important process in tissue development and wound healing. The Tie-2 receptor tyrosine kinases and ligands, angiopoietin (Ang)-1 and -2 have been postulated to play key roles in vascular development. The purpose of this study was to evaluate the expression of Tie-2 and Ang-1 and -2 in an acetic acid-induced gastric ulcer healing process in rats. Methods. Gastric specimens were obtained at 0 (control), 1, 3, 5, 7, and 14 days after ulcer induction for reverse transcription polymerase chain reaction (RT-PCR), Western blot analysis, and immunohistochemical analysis. Results. Expression of Tie-2 and Ang-1 and -2 mRNAs was detected in normal gastric tissue and ulcerative tissues by RT-PCR. Western blot analysis revealed that Tie-2 expression reached a maximum on the third to fifth days. Expression of Ang-1 and -2 peaked on the first day. Ang-1 expression gradually became weaker in 2 weeks, whereas Ang-2 expression returned to normal in a few days. Immunohistochemically, Tie-2 was expressed constitutively in the endothelial cells of pre-existing vessels of the gastric wall, and Tie-2 expression was increased in the new capillaries of the ulcer base. Conclusions. These findings suggest that Tie-2 and Ang-1 and -2 play an important role in angiogenesis in the early phase of ulcer healing.