Reaction of nonenzymic fibrinolysis to intravenous injection of small doses of salmonella endotoxin into rabbits

1984 ◽  
Vol 98 (4) ◽  
pp. 1337-1340
Author(s):  
D. T. Esartiya ◽  
V. E. Pastrova
Keyword(s):  
Intravenous Injection ◽  
Salmonella Endotoxin ◽  
Small Doses

Lauric Acid-Induced Thrombocytopenia and Thrombosis in Rabbits

1967 ◽  
Vol 18 (01/02) ◽  
pp. 057-065 ◽  
Author(s):  
G Zbinden
Keyword(s):  
Acid Solution ◽  
Intravenous Injection ◽  
Lauric Acid ◽  
Repeated Administration ◽  
Intravenous Dose ◽  
Acid Injection ◽  
Small Doses ◽  
High Doses

SummaryIntravenous injection of 0.5% lauric acid solution into rabbits caused moderate to marked thrombocytopenia. With small doses (2.5 mg/kg) this thrombocyte decrease was reversible and microscopically demonstrable thrombosis in the lungs was only seen or suspected in a small number of rabbits 10 to 30 min after lauric acid injection. High doses were followed by partly reversible thrombocytopenia and by moderate to marked, sometimes lethal, thrombosis in the lungs still demonstrable 24 hrs after injection. Repeated administration of small doses of lauric acid did not lead to a depletion of the circulating thrombocytes. Thrombocytopenic response, however, appeared to be less pronounced after the second and subsequent injections. Studies with Cr51-labeled platelets indicate that during the reversible thrombocytopenia following a small intravenous dose of lauric acid platelets are retained in various organs, particularly the lungs.

FURTHER STUDIES OF THE PHARMACOLOGY OF THE PYLORIC REGION: ANALYSIS OF THE EFFECTS OF INTRA-ARTERIAL HISTAMINE, SEROTONIN, PHENYLDIGUANIDE, MORPHINE, AND OTHER DRUGS ON THE ANTRUM AND DUODENAL BULB

1966 ◽  
Vol 44 (6) ◽  
pp. 981-1019 ◽  
Author(s):  
E. E. Daniel
Keyword(s):  
Intravenous Injection ◽  
Contractile Activity ◽  
Duodenal Bulb ◽  
Gastroepiploic Artery ◽  
Low Doses ◽  
Common Site ◽  
Site Of Action ◽  
Small Doses ◽  
Release Of Acetylcholine ◽  
High Doses

The actions of drugs on the antrum and duodenum of the dog were analyzed by the use primarily of intra-arterial injections into the gastroepiploic artery while the electrical and contractile activity of these regions was recorded. Histamine (0.1 to 5 μg) usually caused excitation of second potentials (antrum) or fast spikes (duodenum), and contractions (both) and other effects similar to those produced by acetylcholine, though usually delayed in onset and more prolonged. Its effects were diminished or prevented by atropine, nicotine, and hexamethonium as well as by antihistaminics such as antazoline, cyproheptadine, and phenoxybenzamine. In the duodenum, histamine excitation was usually preceded by inhibition, and most antihistaminics also depressed responses to serotonin (5-HT), acetylcholine, or both. Low doses of serotonin (0.1 to 1 μg) most frequently caused excitation of the antrum and duodenum similar to that evoked by acetylcholine. This response was sometimes prolonged. These effects in the antrum were diminished or prevented by atropine, nicotine, methysergide, and bromolysergic acid (BOL), and less effectively antagonized by hexamethonium, morphine, and pronethalol. Phenoxybenzamine did not prevent excitation of the antrum by low doses of 5-HT, but tachyphylaxis following high doses of 5-HT (5 to 100 μg) or of phenyldiguanide (25 to 500 μg) did prevent such responses. Several of these agents also inhibited excitation of the duodenum induced by 5-HT and cross tachyphylaxis between 5-HT and phenyldiguanide was also observed. It was suggested that low doses of 5-HT, like phenyldiguanide, acted at a preganglionic site in the antrum and duodenum different from that at which histamine acts, presumably the non-medullated mucosal mechanoreceptors, and ultimately caused release of acetylcholine from postganglionic fibers. Phenyldiguanide in small doses (2 to 25 μg) acted like 5-HT to excite the antrum and duodenum. Analysis of its action with antagonists yielded results similar to those with 5-HT, and the occurrence of cross tachyphylaxis with 5-HT suggested a common site of action. Morphine (10 to 1000 μg) usually inhibited electrical and contractile activity in the antrum and stimulated these activities in the duodenum. The same results were obtained with intravenous injection (0.1 to 0.35 mg/kg). It. diminished responses to histamine, 5-HT, phenyldiguanide, and to a lesser extent, acetylcholine.

scholarly journals The metabolism of [14C]nicotine in the cat

1969 ◽  
Vol 115 (5) ◽  
pp. 889-896 ◽  
Author(s):  
D. M. Turner
Keyword(s):  
Single Dose ◽  
Quantitative Determination ◽  
Intravenous Injection ◽  
Body Fluids ◽  
Small Doses ◽  
The Brain

The metabolism of [2′−14C]nicotine given as an intravenous injection in small doses to anaesthetized and unanaesthetized cats has been studied. A method is described for the quantitative determination of [14C]nicotine and [14C]cotinine in tissues and body fluids. Nanogram amounts of these compounds have been detected. After a single dose of 40μg. of [14C]nicotine/kg., 55% of the injected radioactivity was excreted in the urine within 24hr., but only 1% of this radioactivity was unchanged nicotine. [14C]Nicotine is metabolized extremely rapidly, [14C]cotinine appearing in the blood within 2·5min. of intravenous injection. [14C]Nicotine accumulates rapidly in the brain and 15min. after injection 90% of the radioactivity still represents [14C]nicotine. Metabolites of [14C]nicotine have been identified in liver and urine extracts. [14C]Nicotine-1′-oxide has been detected in both liver and urine.

Induction of hepatic egg granuloma hyporesponsiveness in murine schistosomiasismansoniby intravenous injection of small doses of soluble egg antigen

Apmis ◽  
1997 ◽  
Vol 105 (7-12) ◽  
pp. 773-783 ◽  
Author(s):  
HANAA HASSANEIN ◽  
MAHA AKL ◽  
ZEINAB SHAKER ◽  
HANAN EL-BAZ ◽  
RAGIA SHARMY ◽  
...  
Keyword(s):  
Intravenous Injection ◽  
Small Doses ◽  
Egg Antigen

Review of the Radiation Damage Problem of Organic Specimens in Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 476-477
Author(s):  
L. Reimer
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Irradiation Time ◽  
Dose Effect ◽  
Primary Process ◽  
Thin Specimen ◽  
Secondary Damage ◽  
Small Doses ◽  
Micro Organisms ◽  
Damage Processes

Most information about a specimen is obtained by elastic scattering of electrons, but one cannot avoid inelastic scattering and therefore radiation damage by ionisation as a primary process of damage. This damage is a dose effect, being proportional to the product of lectron current density j and the irradiation time t in Coul.cm−2 as long as there is a negligible heating of the specimen.Therefore one has to determine the dose needed to produce secondary damage processes, which can be measured quantitatively by a chemical or physical effect in the thin specimen. The survival of micro-organisms or the decrease of photoconductivity and cathodoluminescence are such effects needing very small doses (see table).

The Local Sanarelli-Shwartzman Phenomenon in Rats Induced by Human Leukaemic Cells

1973 ◽  
Vol 29 (02) ◽  
pp. 353-362
Author(s):  
J Lisiewicz ◽  
A Pituch ◽  
J. A Litwin
Keyword(s):  
Chronic Lymphocytic Leukaemia ◽  
Intravenous Injection ◽  
Peripheral Blood ◽  
Lymphocytic Leukaemia ◽  
Acute Myeloblastic Leukaemia ◽  
Demarcation Line ◽  
E Coli ◽  
Leukaemic Cells ◽  
Shwartzman Phenomenon

SummaryThe local Sanarelli-Shwartzman phenomenon (SSP-L) in the skin of 30 rats was induced by an intr a cutaneous sensitizing injection of leukaemic leucocytes isolated from the peripheral blood of patients with chronic lymphocytic leukaemia (CLL), acute myeloblastic leukaemia (AL) and chronic granulocytic leukaemia (CGL) and challenged by an intravenous injection of 100(μ of E. coli endotoxin. SSP-L was observed in 7 rats after injection of CLL lymphocytes and in 6 and 2 rats after AL myeloblasts and the CGL granulocytes, respectively. The lesions in the skin after AL myeloblasts appeared in a shorter time and were of longer duration compared with those observed after CLL lymphocytes and CGL granulocytes. Histologically, the lesions consisted of areas of destruction in the superficial layers of the skin ; the demarcation line showed the presence of neutrophils, macrophages and erythrocytes. Haemorrhages and fibrin deposits near the demarcation line were larger after injection of CLL lymphocytes and AL myeloblasts than after CGL granulocytes. The possible role of leucocyte procoagulative substances in the differences observed have been discussed.

Ultrastructural Changes of the Tissue Thromboplastin after Intravenous Injection in Rabbits

1978 ◽  
Vol 39 (01) ◽  
pp. 201-209 ◽  
Author(s):  
Hiroshi Hasegawa ◽  
Hiroshi Nagata ◽  
Makoto Murao
Keyword(s):  
Intravenous Injection ◽  
Vascular Endothelium ◽  
Model Experiment ◽  
Venous Return ◽  
Ultrastructural Changes ◽  
Membrane Structures ◽  
Tissue Thromboplastin ◽  
Short Time ◽  
Sheet Membrane

SummaryAttempts were made to demonstrate ultrastructural changes of the tissue thromboplastin after intravenous injection, as a model experiment on the pulmonary microthrombi formation induced by the tissue thromboplastin circulating from venous return.Concentrically arranged membrane structures of the injected thromboplastin disappeared in extremely short time after the injection of the thromboplastin in rabbits. The long sheet membrane of the injected thromboplastin was frequently seen as adhered to the vascular endothelium or to the surface of blood corpuscles. Furthermore, fibrin fibres were formed in contact with the long sheet membrane of the thromboplastin. Membrane structures were not found anywhere in the control rabbits.

Turnover of Human Extrinsic (Tissue-Type) Plasminogen Activator in Rabbits

1981 ◽  
Vol 46 (03) ◽  
pp. 658-661 ◽  
Author(s):  
C Korninger ◽  
J M Stassen ◽  
D Collen
Keyword(s):  
Plasminogen Activator ◽  
Intravenous Injection ◽  
Active Site ◽  
Half Life ◽  
Degradation Products ◽  
Gel Filtration ◽  
Tissue Type ◽  
Organ Distribution ◽  
Small Rise

SummaryThe turnover of highly purified human extrinsic plasminogen activator (EPA) (one- and two-chain form) was studied in rabbits. Following intravenous injection, EPA-activity declined rapidly. The disappearance rate of EPA from the plasma could adequately be described by a single exponential term with a t ½ of approximately 2 min for both the one-chain and two-chain forms of EPA.The clearance and organ distribution of EPA was studied by using 125I-labeled preparations. Following intravenous injection of 125I-1abeled EPA the radioactivity disappeared rapidly from the plasma also with a t ½ of approximately 2 min down to a level of 15 to 20 percent, followed by a small rise of blood radioactivity. Gel filtration of serial samples revealed that the secondary increase of the radioactivity was due to the reappearance of radioactive breakdown products in the blood. Measurement of the organ distribution of 125I at different time intervals revealed that EPA was rapidly accumulated in the liver, followed by a release of degradation products in the blood.Experimental hepatectomy markedly prolonged the half-life of EPA in the blood. Blocking the active site histidine of EPA had no effect on the half-life of EPA in blood nor on the gel filtration patterns of 125I in serial plasma samples.It is concluded that human EPA is rapidly removed from the blood of rabbits by clearance and degradation in the liver. Recognition by the liver does not require a functional active site in the enzyme. Neutralization in plasma by protease inhibitors does not represent a significant pathway of EPA inactivation in vivo.

Inhibition of Fibrinoid Deposition by Heparin

1961 ◽  
Vol 06 (01) ◽  
pp. 157-159 ◽  
Author(s):  
Saul B. Gilson
Keyword(s):  
Intravenous Injection ◽  
Gamma Globulin ◽  
Physiological Significance

ConclusionExperimental glomerulitis in rabbits following intravenous injection of gamma globulin was inhibited by heparinization. The physiological and patho-physiological significance of this observation is considered.

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