The relation of brain eicosanoids to progression of cerebral edema was studied in stroke-resistant spontaneously hypertensive rats subjected to incomplete global brain ischemia induced by bilateral occlusion of the common carotid arteries. Thromboxane B 2 and 6-keto prostaglandin F lo levels were significantly elevated 5 minutes after reperfusion but returned to control levels by 30 minutes. In contrast, leukotriene C 4 levels increased 2 hours after bilateral common carotid artery occlusion and peaked 30 minutes after reperfusion, with higher levels persisting until 60 minutes after reperfusion. Cerebral ischemia was accompanied by cerebral edema early after reperfusion. The edema correlated with increased leukotriene C 4 levels. That the increased brain water content was causally related to an increase in leukotriene C 4 was supported by results obtained following administration of the 5-lipoxygenase inhibitors ONO-LP-016 and AA-861. Both inhibitors suppressed the increased leukotriene C 4 and brain water contents after reperfusion. Our results indicate that leukotriene C 4 is closely associated with an induction of ischemic cerebral edema. (Stroke 1988;19:372-377) F atty acids are liberated from the plasma membranes of ischemic tissue through various pathways. 1 " 3 It is believed that these free fatty acids, particularly arachidonic acid, aggravate cell damage imposed on ischemic brain. Arachidonic acid has been the focus of repeated investigation as it relates to brain edema* 4 " 8 and endothelial cell damage of cerebral arteries.
9When the brain is subjected to severe ischemia, the amount of free arachidonic acid increases abruptly and then decreases gradually when circulation is restored. Since increased levels of arachidonic acid persist when the oxygen supply is restored, conditions exist for enhanced oxidation of arachidonic acid. For example, recirculation is accompanied by a prominent increase in prostaglandins, 10 " 12 which are formed from arachidonic acid by cyclooxygenase. Among these prostaglandins, thromboxane A 2 (TXA 2 ), which is derived primarily from platelets, has potent platelet aggregating and vasoconstrictor effects. By contrast, prostaglandin I 2 (PGI 2 ), which is derived predominantly from vascular endothelial cells, acts to prevent platelet aggregation and vasoconstriction. TXA 2 and PGI 2 are rapidly converted to the stable metabolites TXB 2 and 6-keto-PGF,,,. Received August 30, 1986; accepted September 3, 1987. 5-lipoxygenase dehydrase to leukotrienes. Of these substances, leukotriene C 4 (LTC 4 ) has particularly strong vasoconstrictor activity and promotes increased vascular permeability, perhaps by damage to the blood-brain barrier.
1516We examined the effect of incomplete global cerebral ischemia on the levels of TXB 2 , 6-keto-PGF, a , and LTC 4 in the brain of stroke-resistant spontaneously hypertensive rats (SHRSR) and the relation between LTC 4 and the progression of cerebral edema. (2-Amino -4 -1 -butyl -6-(ct-hydroxy-4-chlorobenzy l)phenolhydrochloride (ONO-LP-01...
Cells (1 X 10(7)/0.5 ml) from a Borrmann type III poorly differentiated adenocarcinoma of the human stomach were injected ip into nude mice. The injection resulted in ascites carcinoma with invasion (carcinomatous peritonitis) and liver metastasis. The inoculum was obtained from subcutaneous tumors at passage 9 in nude mice that had received serial transplants from the patient with Borrmann type III poorly differentiated adenocarcinoma of the stomach. Serial transfers of 1.5 X 10(6) dispersed cancer cells/0.5 ml into the peritoneal cavity of nude mice converted this adenocarcinoma to an ascites form. Hemorrhagic ascites accumulated within 3 weeks at the first passage and 4-6 weeks in serial passages. Carcinomas peritonitis occurred consistently and was observed in the diaphragm, mesenteries, omentum, and pancreas; metastases were seen in the liver and spleen. Subsequently, iv injection of ascites at passage 3 (6 X 10(5) cells/0.2 ml) into nude mice produced metastatic lesions in the lung and the heart. The histology of the invasive and metastatic lesions in the nude mice was similar to that of the original tumor in the patient with stomach carcinoma.
A case of a hernia traversing the lesser sac with a primary defect in the greater omentum and a secondary defect in the lesser omentum is reported herein. This type of internal hernia is extremely rare and we have found only three other reported cases apart from our case. All four cases in whom this type of hernia occurred were young people. The general manifestation resembles acute intestinal obstruction and a plain radiograph shows obstruction of the upper small intestine. An erect lateral view of the abdomen often shows the anatomical location more clearly. Bowel resection was performed in two cases and all of the four reported cases recovered uneventfully.
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