Lead potentiation of endotoxin lethality in rats: Lack of effect of kininase inhibition

Summary Although lead and SQ₂₀₈₈₁ are potent in vitro inhibitors of kininase II activity, SQ₂₀₈₈₁ does not alter the sensitivity of rats to endotoxin. These results indicate that marked changes in plasma kininase activity do not contribute to endotoxin morbility and that kininase inhibition is not the mechanism whereby lead ions sensitize rats to endotoxin.This investigation was supported by the Naval Medical Research and Development Command, NNMC, Department of the Navy, Research Task No. MR041.20.01.0435. The opinions and assertions contained herein are the private ones of the author, and are not to be construed as official or reflecting the views of the Navy Department or the naval service at large.The experiments reported herein were conducted according to the principles set forth in the Guide for the Care and Use of Laboratory Animals, Institute of Laboratory Animal Resources, National Research Council, DHEW Pub. No. (NIH) 74-23.     

Lack of effect ofTris-(hydroxymethyl)aminomethane upon myocardial contractility

Résumé Pour étudier l'action du THAM sur la contractilité, dans une préparation de myocarde isolé, on a réalisé des expériences, où l'on compare l'effet de remplacer une solution de Ringer contenant 30 mM/l de CO₃HNa, équilibrée avec une pCO₂ de 40 mm Hg (pH 7,40), par une solution de THAM ayant le même pH avec le même pCO₂. Les résultats ont permis de conclure que le THAM n'a aucune influence inotrope positive sur la contractilité, lorsque le pH extracellulaire et le pCO₂ restent invariables.     

Enhancing effect of insulin on endotoxin lethality

Résumé Nous avons constaté que les souris traitées à l'insuline possèdent une sensibilité élevée à l'endotoxine de bactéries à gram négatif. Ce résultat concorde avec l'hypothèse d'une relation inverse entre la quantité de glucose dans le sang et la sensibilité d'un hôte à une grande variété de «Stressors».     

The effect of pretreatment with rat placental homogenate on subsequent pregnancy in the rat

Résumé L'effet d'un traitement immunologique sur la grossesse du rat a été étudié. Les animaux du groupe expérimental ont reçu 8 injections d'homogénat placentaire à raison de deux par mois, puis ont été accouplés. Après 21 jours de grossesse il y avait moins de fétus nés vivants que dans le groupe témoins non-traité; le poids des fétus en vie était en général normal mais on a noté une augmentation significative de la masse placentaire par rapport au groupe témoin.     

The effect of semicarbazide pretreatment on the depressant action of barbiturates

Résumé Le pentobarbital fait diminuer la transmission à travers le relais monosynaptique de la moelle épinière chez les chats décapités dépourvus de GABA sous un traitement au semicarbazide, et ceci par un degré équivalent à celui des expériences de contrôle.     

Lack of gravity effect on the speed of amoeboid locomotion inNaegleria gruberi

Summary The speed of amoeboid locomotion was the same for amoebae moving on the top surface and bottom surface of a horizontal perfusion chamber i.e. cell-substrate adhesive forces must be considerably greater than the gravitational force acting on the locomoting amoeba.Acknowledgments. We would like to thank Les Cooper for technical assistance, and the Science Research Council for support.     

The effect of endotoxin on the lactic acid production in pregnant and non-pregnant rats

Zusammenfassung Die Milchsäureproduktion ist im Knochenmark und in den Leukozyten trächtiger Tiere infolge Endotoxineinwirkung signifikant höher als bei Kontrolltieren. Während sich die Milchsäureproduktion endotoxinbehandelter Plazenten infolge Dauerhemmung der aeroben Glykolyse völlig von allen untersuchten Geweben unterscheidet, bleibt der Sauerstoffverbrauch unverändert.     

Lack of pressor effect of dopamine in the pentobarbital-anesthetized rat

The blood pressure and heart rate responses to intravenous dopamine infusion at 2.5, 5.0 and 10.0 micrograms.min-1 X 100 g-1 were studied in conscious and pentobarbital-anesthetized Sprague-Dawley rats. In the conscious rats, dopamine caused a significant dose-related increase in the mean arterial blood pressure which was abolished in the anesthetized rats. The heart rate increased significantly only at the highest dose infused. The responses to equipressor doses of noradrenaline (40 ng.min-1 X 100 g-1) and phenylephrine (1.0 micrograms.min-1 X 100 g-1) were also suppressed in the anesthetized rats. The results suggest that pentobarbital anesthesia depresses the blood pressure response to dopamine infusion in the rat through a depression of activation of alpha-adrenoceptors.     

Lack of pressor effect of dopamine in the pentobarbital-anesthetized rat

Summary The blood pressure and heart rate responses to intravenous dopamine infusion at 2.5, 5.0 and 10.0 g·min^–1·100 g^–1 were studied in conscious and pentobarbital-anesthetized Sprague — Dawley rats. In the conscious rats, dopamine caused a significant dose-related increase in the mean arterial blood pressure which was abolished in the anesthetized rats. The heart rate increased significantly only at the highest dose infused. The responses to equipressor doses of noradrenaline (40 ng·min^–1·100 g^–1) and phenylephrine (1.0 g·min^–1·100 g^–1) were also suppressed in the anesthetized rats. The results suggest that pentobarbital anesthesia depresses the blood pressure response to dopamine infusion in the rat through a depression of activation of alpha-adrenoceptors.16 June 1986     

Adenyl cyclase activity of mouse liver membranes after incubation with endotoxin and epinephrine

Summary Adenyl cyclase activity in isolated mouse liver cell membranes was stimulated two-fold by endotoxin. Furthermore, endotoxin inhibited epinephrine induction of adenyl cyclase activity, apparently through interruption of the phospholipid moiety of the enzyme complex.     

The effect of endotoxin on membrane fatty acid composition in BCG-sensitized mice

The effects of endotoxin on mouse liver phospholipid fatty acid composition have been investigated. Administration of endotoxin from Salmonella abortus equi led to a decrease in the polyunsaturated fatty acid content of livers from mice sensitized with Bacille Calmette Guérin (BCG). The content of arachidonic acid fell significantly in both the phosphatidylcholine and phosphatidylinositol fractions whereas in the phosphatidylethanolamine fraction the linoleic acid content was significantly reduced. The polyunsaturated fatty acids were replaced by increased amounts of oleic acid and palmitic acid, leading to a reduction in the polyunsaturated to saturated fatty acid ratio.     

Lack of effect of colchicine on human neutrophil chemotaxis under agarose

Summary Human polymorphonuclear neutrophil chemotaxis under agarose was assessed following in vitro treatment of cells with colchicine. No inhibition of random migration or chemotaxis was detected. The discrepancy between these results and reports utilizing micropore filter assays could be due to the need for cell deformability in the latter.Supported by a grant from the Veterans Administration and Research grant AM 19349 from the NIAMDD, NIH.     

Protective effect of native levan on endotoxin toxicity in mice and rats

Summary High polymer levan administered to mice and rats before the injection of endotoxin partly protects the animals from the lethal effects of the LPS.This study summarizes a thesis in partial fulfilment of the requirements for the degree of Master of Medical Sciences in the School of Continuing Medical Education of the Tel-Aviv University Sackler Medical School.