Several substances have been shown to affect hepatic heme synthesis in the rat liver. Phenobarbital and the polycyclic hydrocarbon, 3,4-benzpyrene, produce an induction of aminolevulinic acid synthetase (ALAS), the enzyme mediating the first step in heme synthesis. This is followed sequentially by increased incorporation of glycine into microsomal heme, increased microsomal protoheme, cytochrom...

In earlier work (1) a DPNH’-specific microsomal cytochrome reductase, liberated by alcohol extraction and partially purified, was identified in liver microsome fractions from rats and rabbits. Microsomal cytochrome, but not cytochrome c, was found to act as electron acceptor in the oxidation of DPNH catalyzed by the enzyme. Through a rapid cytochrome to cytochrome reaction, cytochrome c was red...

The effects of three different enzyme-inducing agents (phenobarbital, 3-methylcholanthrene and rifampicin) on plasma and liver microsomal fraction paraoxonase and arylesterase were studied in rats. Although phenobarbital and 3-methylcholanthrene each increased the esterase activities in microsomal fraction, only 3-methylcholanthrene was capable to increase them in plasma. By contrast, the admin...

Detailed studies on the hydrolysis of p-acetylphenyl sulphate and oestrone sulphate by rat liver preparations strongly indicate that arylsulphatase C and oestrogen sulphatase are the same enzyme. Liver is the richest source of both enzymes, which have identical intracellular distributions, being localized mainly in the microsomal fraction. Low oestrogen sulphatase and arylsulphatase C activitie...

Tryptophan pyrrolase, the enzyme that catalyzes the oxidation of tryptophan to formylkynurenine, has been localized in the 11,000 X g supernatant fraction of mammalian liver homogenates (l), which contains microsomes and cell sap. In the course of the present investigations (Z), it was observed that the isolated microsomal fraction of rat liver is devoid of this enzyme. However, addition of thi...

1. The detergent Triton X-100 activates UDP glucuronyltransferase from rat liver in vitro six- to seven-fold with p-nitrophenol as substrate. The enzyme activity when measured in the presence of Triton X-100 is increased significantly by pretreatment of male rats with phenobarbital for 4 days (90mg/kg each day intraperitoneally). If no Triton X-100 is applied in vitro such an increase could not...

Rat liver, kidney, pancreas, and small intestine have enzymes which hydrolyze fatty acid esters of carnitine. The liver enzyme, located in the microsomal fraction, was solubilized by sonic disruption and purified l&fold by diethylaminoethyl cellulose chromatography and Sephadex gel filtration. The purified enzyme sedimented in the ultracentrifuge as a single protein with an szo+, of 4.5 S. The ...

Lubricant-infused surfaces (LIS) have emerged as an innovative way to combat several modern challenges such biofouling, ice formation, and surface drag. The favorable properties of LIS are depen...