Enzymes intoxication

Assays of ciguatoxin. Determination of ciguatoxin levels in fish was carried out in many laboratories by mouse assays. Enzyme immunoassay to screen inedible fish has been proposed by Hokama (9). No specific chemical assay has been developed, as information on functional groups suitable for fluorescence labeling is not available. Analyses conducted in the authors laboratory on remnant fish retrieved from patients meals indicated that ciguatoxin content as low level as 1 ppb could cause intoxication in adults. An extremely high sensitivity and a sophisticated pretreatment method will be required for designing a fluorometric determination method for the toxin. 

Urine concentrations of PCP determined by enzyme immunoassay did not correlate with the state of intoxication at the time the urine sample was taken. The test was negative in 15 percent of 1,000 patients with clinical evidence of PCP toxicity, many of whom admitted taking PCP (McCarron et al. 1981a). Several of these negative urines were analyzed for PCP analogues none were found. 

Zinc is in the active site of ALAD and can play a protective role in lead intoxication by reversing the enzyme-inhibiting effects of lead. Children with high PbB levels (50-67 pg/dL) were reported to consume less zinc than children with lower PbB (12-29 pg/dL) (Johnson and Tenuta 1979). In a group of 13 children, Markowitz and Rosen (1981) reported that the mean serum zinc levels in children with... 

Iron appeared to reduce the effects of orally or subcutaneously administered lead on blood enzyme and liver catalase activity (Bota et al. 1982). Treatment of pregnant hamsters with iron- or calcium-deficient diets in conjunction with orally administered lead resulted in embryonic or fetal mortality and abnormalities (ranting, edema) in the litters, while treatment with complete diets and lead did not (Carpenter 1982). Inadequate levels of iron in association with increased body burdens of lead enhanced biochemical changes associated with lead intoxication (Waxman and Rabinowitz 1966). Ferrous iron was reported to protect against the inhibition of hemoglobin synthesis and cell metabolism by lead it has been speculated that iron competes with lead uptake by the cell (Waxman and Rabinowitz 1966). In... 

No data were found on the effects of silver compounds on avian or mammalian wildlife. All controlled studies with silver were with domestic poultry, livestock, or small laboratory mammals. Signs of chronic silver ion intoxication in tested birds and mammals included cardiac enlargement, vascular hypertension, hepatic necrosis, anemia, lowered immunological activity, altered membrane permeability, kidney pathology, enzyme inhibition, growth retardation, and a shortened life span (Smith and Carson 1977 Freeman 1979 Fowler and Nordberg 1986 USPHS 1990). 

Recently we have evaluated several exogenous and endogenous tests of liver function in rainbow trout following intoxication by the model hepatotoxicant CCl. The results of these studies indicate that elevated plasma activity of the enzyme glutamate-pyruvate transaminase (GPT) is the most sensitive endogenous index of... 

As we soon learned, tetrahydro-aminoaeridine (THA) is less effeetive in some respeets than physostigmine in reversing seopolamine induced decrements in NF% scores (Fig. 67) but surprisingly, does seem to shorten the duration of belladonnoid intoxication. This may reflect a greater affinity for the cholinesterase enzyme. THA s tendency to cause temporaiy liver enzyme abnormalities, however, persuad us to avoid its further use. 

Cyanide ion exerts an inhibitory action on certain metabolic enzyme systems, most notably cytochrome oxidase, the enzyme involved in the ultimate transfer of electrons to molecular oxygen. Because cytochrome oxidase is present in practically all cells that function under aerobic conditions, and because the cyanide ion diffuses easily to all parts of the body, cyanide quickly halts practically all cellular respiration. The venous blood of a patient dying of cyanide is bright red and resembles arterial blood because the tissues have not been able to utilize the oxygen brought to them. Cyanide intoxication produces lactic acidosis, the result of an increased rate of glycolysis and production of lactic acid. ... 

At least four fatal, several severe nonfatal, and a number of mild cases of demeton intoxication have been reported. Both animal experiments and human exposures suggest that the toxicity and potency of demeton is similar to that of parathion. Signs and symptoms of overexposure are caused by the inactivation of the enzyme cholinesterase, which results in the accumulation of acetylcholine at synapses in the nervous system, skeletal and smooth muscle, and secretory glands.The sequence of the development of systemic effects varies with the route of entry. The onset of signs and symptoms is usually prompt but may be... 

Matkovics B, Novak R, Szabo L, et al. 1978. Effect of acute carbon tetrachloride intoxication on the lipid peroxidation and the enzymes of the perioxide metabolism of rat tissues. Gen Pharmacol... 

Teschke R, Vierke W, Goldermann L. 1983. Carbon tetrachloride (CCH) levels and serum activities of liver enzymes following activities CCh intoxication. Toxicol Lett 17 175-180. 

Hong, N. D., J. W. Kim, B. W. Kim, and J. G. Shon. Studies on the efficacy of the combined preparation of crude drugs. 6. Effect of Saengkankunbi-tang on activities of the liver enzyme, protein contents and the excretory action of bile juice in the serum of CCL4-intoxicated rabbits. Korean J Pharmacog 1982 13 33-38. 

Villard, B. Lacarelle, J. Catalin, and B. Bruguerolle. Effects of different exposure times to tobacco smoke intoxication on carboxyhemoglobin and hepatic enzymate activities in mice. J Pharmacol Toxicol Methods 1996 35(4) 211-215. 

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