The role of prostanoids in the feline intestinal vascular and central haemodynamic responses to i.v. infusion of live E. coli

Abstract

Bacterial infusion in the cat, causing experimental septic shock, induces an early vascular response mainly characterized by pulmonary hypertension and intestinal vasoconstriction. Prostanoids are held to be important mediators of the pulmonary vascular reaction. This study was performed to explore the involvement of prostanoids in the central haemodynamics and the small intestinal vascular reactions in experimental septic shock. Aortic blood pressure was continuously monitored, as were aortic blood flow, the pressure in a. pulmonalis and the small intestinal venous outflow. All cats (n = 24) were given live E. coli (10(10) ml-1) as a continuous intravenous infusion. One series was pretreated with indomethacin, another with UK-38,485, a specific thromboxane A2 synthetase inhibitor, and a third series served as untreated control. The pulmonary hypertensive response was clearly attenuated in the two pretreated series, in fact abolished in the one given UK-38,485. The early intestinal vasoconstriction was eliminated in the two pretreated series. Later during bacteraemia, when untreated and indomethacin-pretreated cats showed intestinal vasoconstriction, UK-38-485-pretreated animals kept intestinal blood flow within the preseptic range. These data suggest that in the cat, thromboxane A2 is the prostanoid mediating the vascular reactions, not only in the lung but also in the small intestine.

Human CD4 and human major histocompatibility complex class II (DQ6) transgenic mice: supersensitivity to superantigen‐induced septic shock

“…Animal models of Gram-negative septicemia range from mice [40, 411, rats [42], and guinea pigs [43], to rabbits [44], cats [45], dogs [46], to large farm animals such as pigs [47, 481, sheep [49] and horses [50], to primates including baboons [51,521, and rhesus monkeys [53]. Each of these animal models mimics the clinical and laboratory responses in endotoxic shock in humans.…”

Feline pulmonary hypertension: are we overlooking an important comorbidity?

“…In other models of PAH, the Escherichia coli endotoxin was infused into cats, to induce PAH, and, with this, the modification of PAH in the presence of various vasoactive compounds. [69][70][71][72] Sleep apnea has been described in the cat; however, as yet, PH has not been described in association with sleep apnea in cats. 73 Furthermore, no studies have assessed the effect of chronic exposure to high altitude on the feline pulmonary vasculature.…”

“…In other models of PAH, the Escherichia coli endotoxin was infused into cats, to induce PAH, and, with this, the modification of PAH in the presence of various vasoactive compounds. 69–72…”