thromboxane-b2 and Intestinal-Obstruction

In the present study the significance of eicosanoids in the development of shock in horses on the basis of ileus has been investigated using the prostanoids thromboxane B2 (TXB2) and prostaglandine E2 (PGE2) as indicators. The prostanoid synthesis inhibitor flunixin meglumine was to be examined regarding its efficacy in the effective blockade of the synthesis of these mediators within the peri-operative timeframe as well as its effects on clinical signs and laboratory parameters. 21 horses suffering from ileus and ready for surgical intervention received an intravenous flunixin dosis of 1.1 mg/kg body weight immediately after the initial examination and prior to the surgical procedure. 20 colic horses receiving surgical treatment without application of the drug served as control group. Reference data concerning the approximate standard plasma levels of the prostanoids were determined in 10 healthy horses. Plasma levels of thromboxane B2 and prostaglandine E2 in all colic horses, treatment group as well as controls, initially proved to be significantly higher than the reference values in healthy horses. The untreated control group showed plasma levels highly exceeding the standards within the course of investigation. The application of flunixin meglumine resulted in an effective inhibition of the prostanoid synthesis. Post-operatively as well as within the whole period of investigation the plasma levels of PGE2 and TXB2 of the treated group were considerably lower than those of the control group. Flunixin meglumine had a favorable effect on several cardiovascular parameters. The experimental data concerning the effects of flunixin meglumine thus could be validated in a clinical setting, especially the effective inhibition of the cyclooxygenase enzyme system. The application of the prostanoid synthesis inhibitor flunixin meglumine can be judged as being effective in limiting shock progress in the peri-operative setting given reliable diagnosis.

Topics: Animals; Biomarkers; Clonixin; Colic; Dinoprostone; Female; Horse Diseases; Horses; Intestinal Obstruction; Male; Postoperative Period; Prostaglandin Antagonists; Thromboxane B2

Effects of 1 hour of colonic volvulus and 3 hours of reperfusion on concentrations of thromboxane (TXB2) and prostacyclin (6-keto-PGF1 alpha) in portal, pulmonary arterial, and jugular blood were determined by radioimmunoassay to assess the site of production and clearance of these eicosanoids from the circulation in 5 anesthetized ponies. Colonic volvulus had no significant effect on mean arterial pressure or TXB2 concentrations, but significantly (P less than 0.05) increased 6-keto-PGF1 alpha concentrations in all blood samples. Immediately after colonic reperfusion, all eicosanoid concentrations were significantly (P less than 0.05) increased. Then, TXB2 returned to baseline values, whereas 6-keto-PGF1 alpha concentrations remained significantly (P less than 0.05) high for the remainder of the study. Eicosanoid concentrations were significantly (P less than 0.05) greater in portal blood than in pulmonary arterial and jugular blood samples at all periods. This suggests that the splanchnic circulation is the primary site of eicosanoid production during and after colonic volvulus and the liver appears to provide most of the circulatory clearance of thromboxane and prostacyclin.

Topics: Animals; Blood Pressure; Colonic Diseases; Epoprostenol; Female; Horse Diseases; Horses; Intestinal Obstruction; Male; Thromboxane A2; Thromboxane B2

Sclerosing peritonitis is a severe complication after CAPD treatment. The visceral peritoneum is thickened and interenteric adhesive parts are found. Myofibroblasts are proliferated and the collageneous tissue is hyperplastic. The mean clinical symptom is the mechanical obstruction of the small bowel. We observed this illness in three out of sixty patients under CAPD. These patients had higher incidence of bacterial peritonitis. In the ascites high concentrations of PG E2 and Thromboxan B2 were observed. After treatment of the infection the concentrations fell down to normal values. Electronoptical observations from peritoneal biopsies showed a proliferation of myofibroblasts and extracellular lysosomes. It is known from these lysosomes that they are able to set free proteasis. These lead to degredation of fibrin and fibrinogen. These splits are mitogen to myofibroblasts. release from HIT cells could also be evoked by the sulphonylureas glibenclamide and tolbutamide and by an increase in concentration of extracellular K+ to 40 mmol/l. The content of cyclic AMP in HIT cells was increased modestly by glucose but not by an increase in extracellular K+. Forskolin elicited a 4-fold increase in cyclic AMP content. We conclude that HIT cells retain the essential features of the insulin secretory response of normal B cells and represent an important tool for further biochemical characterisation of the secretory system.

Topics: Adult; Bacterial Infections; Dinoprostone; Female; Fibrin; Humans; Intestinal Obstruction; Intestine, Small; Male; Peritoneal Dialysis, Continuous Ambulatory; Peritoneum; Peritonitis; Prostaglandins E; Sclerosis; Thromboxane B2