Hideki Idei

The effect of dopamine on rat gastric motility.

SummaryThe inhibitory mechanism of dopamine (DA) on rat gastric motility was investigated in association with DA receptors. Gastric movement was assessed according to the method of Jacoby et al and was expressed with the system of Ludwick et al. (1968). DA inhibited gastric movement in both the corpus and antrum in a dose-dependent manner. Domperidone, a specific antagonist of DA2 receptor, suppressed DA-induced inhibition of gastric movement in a dose-dependent manner. SCH23390, a specific antagonist of DA1 receptor did not affect DA-induced inhibition of gastric movement. LY171555, a specific agonist of DA2 receptor, inhibited gastric movement in both the corpus and antrum in a dose-dependent manner. SKF38393, a specific agonist of DA1 receptor, did not affect gastric movement. These results indicate that DA plays an important role in the inhibitory regulation of gastric motility, through DA2 receptor but not DA1 receptor.

Role of platelet activating factor on severity of ischemic colitis

PURPOSE: Ischemic colitis develops after a sudden decrease in colonic blood supply and has a variety of clinical manifestations. The aim of this study was to assess the role of platelet activating factor in the pathogenesis of ischemic colitis with use of the platelet activating factor antagonist TCV-309. METHODS: Rats were randomly divided into four groups. Rats in Group RV underwent ring attachment around the rectum to induce partial obstruction and ligation of the marginal vessels of the left colon. As control, rats in Group R underwent the ring attachment and rats in Group V underwent the vascular ligation. Rat in Group C underwent sham operation. The effects of TCV-309 on lesion formation in the colon were evaluated. Thiobarbituric acid reactant level was determined in colonic mucosa, and the incidence and severity of ischemic lesions were also determined. RESULTS: Lesions of colitis were frequently observed in Group RV. TCV-309 did not prevent lesion formation, nor did it suppress the increase in thiobarbituric acid reactant level in Group RV. However, TCV-309 mitigated the severity of the lesion. CONCLUSIONS: Partial obstruction of the colon tends to induce ischemic colitis, and additional ischemia completes lesion formation. Platelet activating factor may play a role in the progression of ischemic lesions.

CLINICOPATHOLOGICAL AND IMMUNOHISTOLOGICAL STUDIES AND PROGNOSIS OF PRIMARY MALIGNANT LYMPHOMA OF THE SMALL INTESTINE

切除した小腸原発性悪性リンパ腫5例を対象に, 臨床病理学, 免疫組織学的検討を行った. 性別は4: 1, 手術時平均年齢は62.2歳, 病悩期間は平均3.3か月であった. 臨床症状は腹痛を全例に認めたが, 悪性リンパ腫に特異的な症状はなかった. 発生部位は空腸1例, 回腸4例, 肉眼型は潰瘍型3例, 動脈瘤型2例で, 腫瘍径は全例4cm以上 (平均8.0cm) と大きく, 多発症例は2例あった. 免疫組織学的検索では全例B細胞由来リンパ腫で, このうち, 2例に腫瘍細胞質内に免疫グロブリン局在を認め, 1例はIgGλ 型, 1例はIgMλ 型であった. 腫瘍径と予後の関連性は見出せなかったが, 深達度, リンパ節転移, 進行度との関連性は示唆できた.