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J K Piotrowski

Publications and source records attributed to J K Piotrowski.

49 records · Page 3Linked to original sources
PubMed1977

A modified procedure for determination of metallothionein-like proteins in animal tissues.

1. The effect of low-molecular-weight substances interfering with determination of metallothionein is eliminated by precipitation of 203Hg-thionein by tannic acid. 2. In animals not exposed to metals, the mean values for metallothionein content in liver and kidney are, respectively, 0.10 and 0.18 mg/g in rats, 0.06 and 0.07 in mice and 0.12 and 0.29 in guinea-pigs, i.e. are 2-3 times lower as compared with the values obtained by the procedure not involving treatment with tannic acid.

Animals↗
PubMed1976

Binding of inorganic mercury by subcellllar fractions and proteins of rat kidneys.

Inorganic mercury, administered to rats in a single dose of 0.5 mg Hg/kg is accumulated in the kidneys mainly in the soluble (54%) and nuclear (30%) fractions, showing decreasing tendency with time. Mitochondrial and microsomal fractions, initially accumulating approx. 11 and 6% of total Hg, show a tendency to increase the absolute level of Hg for the first week after administration. In the soluble fraction low-molecular weight, metallothioneinlike proteins are mainly responsible for the accumulation of mercury, in other fractions proteins of higher molecular weight prevail.

Animals↗
PubMed1976

Influence of certain metals on the level of metallothionein-like proteins in the liver and kidneys of rats.

Rats were given certain metal salts once every other day for six to eight doses and therafter the levels of metallothionein-like proteins (MTP) were determined in their liver and kidneys. The normal level of those proteins ranged from 0.1 to 0.4 mg/g in the liver and 0.2 and 0.6 mg/g in the kidney. Beryllium, magnesium, barium, strontium, tin, arsenic, selenium, chromium, and nickel administration did not influence the tissue levels of MTP. There was a tendency toward increased MTP levels in the liver after the application of high doses of iron. A significant increase in MTP levels in the liver resulted from cobalt administration and in the kidneys of bismuth-treated rats. Applying molecular filtration it was shown that both metals were partially bound in vivo to protein fractions, the molecular weights of which are close to that of metallothionein.

Animals↗
PubMed1975

Effect of repeated exposure to aniline, nitrobenzene, and benzene on liver microsomal metabolism in the rat.

Exposure of rats to aniline at daily doses of 50 mg/kg of body weight over a month stimulated the microsomal metabolism as manifested by (1) acceleration of p-hydroxylation of anilin and N-demethylation of aminopyrine in 9-000 times g postmitochondrial supernatant of the liver, (2) shortening the sleeping time after hexobarbital, and (3) reduction of the antipyretic effect of phenacetin. In the rats exposed to nitrobenzene in a similar manner to aniline, nitroreduction of nitrobenzene and p-hydroxylation of aniline remained unaffected; the antipyretic effect of phenacetin was decreased, whereas hexobarbital sleeping time remained unchanged. Exposure of rats to benzene (50 mg/kg of body weight daily for a month) had no effect on the rate of hydroxylation of benzene and N-demethylation of aminopyrine. In benzene-exposed rats hexobarbital sleeping time was prolonged whereas the antipyretic effect of phenacetin was unaffected. Microsomal metabolism of aniline, nitrobenzene, and benzene was stimulated and inhibited when the rats were pretreated with phenobarbital and SKF 525-A, respectively.

Aminopyrine N-Demethylase↗