retinol-palmitate and Acute-Disease

In the present work the effect of intramuscular administration of 30.000, 50.000 and 100.000 IU of vitamin A palmitate daily for seven days, respectively, on the liver enzyme activity in 45 white male Wistar rats, aged 12 weeks and weighing 180-200 g, have been studied. The group control was integrated by 15 healthy rats with similar characteristics (strain, gender, age and weight) to treated animals. Food and water consumption and body weights were recorded at the end of the experimental period. Rats were observed for clinical signs of toxicity. At the end of the study, rats were sacrificed under ether anesthesia. Liver samples were taken for the determination of enzyme activity. Administration of excess of vitamin A produced a significant (p < 0.05) increase in the content of liver vitamin A, determined diverse and variable clinical signs (such as, anorexia, loss of body weight, alopecia, conjunctivitis, external and internal hemorrhages, skin abnormalities and death) and increased (p < 0.05) the activity of the following enzymes: alanine aminotransferase, aspartate aminotransferase, acid maltase (acid alpha-1,4-glucosidase), acid proteases, lactate dehydrogenase and alkaline phosphatase while glucose-6-phosphatase, glycogen phosphorylase, alpha-amylase, cholinesterase and arginase decreased (p < 0.05) as compared with untreated controls. These changes depend on the doses given of vitamin A. In conclusion, our results provide evidence that short-term administration of high doses of vitamin A determined diverse and variable clinical signs and produces a marked alteration of activity of liver enzymes.

Topics: Acute Disease; Animals; Antioxidants; Diterpenes; Hydrolases; Hypervitaminosis A; Injections, Intramuscular; Liver; Male; Oxidoreductases; Rats; Rats, Wistar; Retinyl Esters; Transferases; Vitamin A

To develop an isolated rabbit lung model in which oxygen free radical activity could be measured and to examine the effects on the model of oxygen free radical scavengers.. Prospective, randomized study.. A clinical and basic research facility attached to a teaching hospital.. Twenty-five New Zealand white rabbits weighing 3.5 to 4.5 kg.. The mechanism of lung injury by oleic acid or by phorbol myristate acetate (20 ng/mL) plus polymorphonuclear neutrophils (PMA-PMN) in an ex vivo rabbit shock lung model may be the production of oxygen free radicals. Using a standard heart-lung preparation from these rabbits, baseline mean pulmonary artery pressure was maintained at 15 mm Hg and the mean airway pressure at 10 mm Hg. Experimental perfusates were infused over 30 minutes, followed by Krebs-Henseleit solution, pH 7.4. Dimethyl pyrroline oxide trapped oxygen free radicals, levels of which were measured by electron paramagnetic resonance spectroscopy. Lung injury was assessed by light and scanning electron microscopy and by lung weight.. A 5-fold increase in pulmonary artery pressure (P < .001) and a nearly 3-fold increase in mean airway pressure (P < .001) were observed in both the oleic acid and PMA-PMN models. Superoxide dismutase (20,000 U/kg), but not retinol palmitate (2000 U), prevented lung injury, the increases in pulmonary artery pressure and mean airway pressure, and the increase in oxygen free radicals in the PMA-PMN model. There were no increases in oxygen free radicals in the control, oleic acid, or PMA-PMN/superoxide dismutase groups (n = 5 in each group). Maximum mean +/- SD increases in oxygen free radicals were 112 +/- 22 nmol/L in the PMA-PMN group (P < .003, n = 5) and 108 +/- nmol/L in the PMA-PMN/retinol group (P < .003, n = 5).. The mechanism of lung injury in the PMA-PMN model is an increase in oxygen free radicals, because superoxide dismutase prevents both the rise in oxygen free radicals and lung injury. Administration of retinol does not prevent lung injury. Oleic acid produces injury not by an increase in oxygen free radicals but rather by another, unknown mechanism.

Topics: Acute Disease; Animals; Anticarcinogenic Agents; Diterpenes; Electron Spin Resonance Spectroscopy; Evaluation Studies as Topic; Free Radical Scavengers; Lung; Lung Diseases; Microscopy, Electron, Scanning; Models, Biological; Prospective Studies; Rabbits; Random Allocation; Reactive Oxygen Species; Respiratory Distress Syndrome; Retinyl Esters; Shock; Superoxide Dismutase; Vitamin A

A recent study reports that patients with previous acute pancreatitis commonly have an abnormal clearance of serum triglycerides after an oral fat load. This observation supports the hypothesis that patients with previous acute pancreatitis and normal fasting serum triglyceride levels may have a preexistent abnormality in the metabolism of chylomicrons. To test this hypothesis, the catabolism of chylomicrons and their remnants was studied in a series of 7 patients who had sustained an attack of pancreatitis (2, gallstone related; 2, alcohol ingestion; 1, hydatid cyst; and 3, no associated pathological condition) at least 18 mo earlier. All the patients had previously had abnormal oral-fat tolerance test results. These patients were compared with a series of 6 healthy volunteers. Chylomicrons were endogenously labeled with an oral dose of retinyl palmitate, and their plasma elimination half-life was calculated. The retinyl palmitate absorption rate constants were similar in control and pancreatitis patients. The chylomicron t1/2 were 2.3 +/- 0.8 (SD) h and 3.9 +/- 1.8 h in the control and pancreatitis groups, respectively (p = 0.07). The chylomicron remnant t1/2 was 2.7 +/- 1.1 h in the control group and 5.2 +/- 2.4 h in the pancreatitis group (p less than 0.05). This study supports the hypothesis that subjects with previous acute pancreatitis may have an abnormality in the catabolism of chylomicron particles. This abnormality may represent a preexistent genetic condition expressed in either the apoprotein composition of chylomicrons or in the hepatic apolipoprotein E-receptor activity.

Topics: Acute Disease; Adult; Cholesterol; Chromatography, High Pressure Liquid; Chylomicrons; Diterpenes; Humans; Lipoproteins, VLDL; Male; Metabolic Clearance Rate; Middle Aged; Pancreatitis; Retinyl Esters; Time Factors; Triglycerides; Vitamin A

Topics: Acute Disease; Chromatography, High Pressure Liquid; Diterpenes; Hepatitis; Humans; Hyperlipidemias; Hypervitaminosis A; Liver Cirrhosis; Reference Values; Retinyl Esters; Specimen Handling; Vitamin A

Topics: Acute Disease; Adolescent; Antineoplastic Combined Chemotherapy Protocols; Child; Cytarabine; Diterpenes; Dose-Response Relationship, Drug; Doxorubicin; Humans; Leukemia; Retinyl Esters; Thioguanine; Vitamin A