In T47D breast cancer cell line, progestin (R5020) induces de novo synthesis of an alkaline phosphatase enzyme. Based on inhibitor profiles and antigenic specificity, it is apparent that this enzyme belongs to the class of membrane-associated tissue-unspecific alkaline phosphatases. Enzyme induction was uniquely specific to progestins and not altered by other steroid hormones or synthetic analo...

Three separate approaches were applied to examine the general relationship between R, the rate of induction of specific enzymes (mitochondrial alpha-glycero-phosphate dehydrogenase and cytosolic malic enzyme) and q, the fractional nuclear occupancy by triiodothyronine in male Sprague-Dawley rats. Daily 200-microgram injections of triiodothyronine per 10u g body wt for 7 days resulted in saturat...

Rats were given a single dose of toxaphene (120 mg/kg, equivalent to 1/2 LD50) and sacrificed at 1, 5, and 15 days. Liver weight and hepatic microsomal enzyme activity were increased at day 5 and 15. The level of plasma testosterone was significantly decreased at day 15. In a second experiment rats were given 2.4 mg/kg daily and sacrificed at 1, 3 and 6 months. Liver weight and microsomal enzym...

HeLa TCRC-1, is a monophenotypic cell line for the production of the carcinoplacental Regan isoenzyme of alkaline phosphatase. It has been previously reported that, when this cell line is grown in immunosuppressed rats, there is an alteration of phenotypic expression in that an isoenzyme that is referred to as oncoamnion (FL) becomes the dominant enzyme form. This report describes the isoenzyme...

The effects of colchicine on lysosomal fusion and lysosomal enzyme induction in the cultivated mouse peritoneal macrophage have been examined. Colchicine (10- minus 6 M), but not lumicolchicine, inhibited lysosomal enzyme induction by both phagocytic and pinocytic stimuli. In addition, the drug significantly retarded pinocytic uptake of [3-H] sucrose and transport of the amino acids [3-H] alpha...

Bock, K. W., Bock-Hennig, B. S., Lilienblum, W. & Volp, R. (1981) Chem.-Biol. Interact. 36, 167-177 Bock, K. W., Lilienblum, W., Pfeil, H. & Eriksson, L. C. (1982) Cancer Res. 42, 3747-3752 Bock, K. W., Burchell, B., Dutton, G. J., Hanninen, O., Mulder, G. J., Owens, I. S., Siest, G. & Tephly, T. R. (1983) Biochem. Pharmacol. 32, 953-955 Bock, K. W., Bock-Hennig, B. S., Fischer, G., Lilienblum,...

tissues (liver, thymus, transplantable tumors) which are responsive to the glucocorti coids. Also, some factors involved in studies on the actions of hormones are considered. The problem of resistance to comtisol and the technics being used to evaluate the physiological significance of enzyme induction by cortisol in target tissues is dis cussed. The various dietary and physiological conditions...

The marine bivalve Lucinoma aequizonata has intracellular chemoautotrophic symbionts residing in the gill tissue. These bacteria are capable of nitrate respiration even under fully saturated oxygen conditions. Nitrate reductase in the symbionts of L. aequizonata appears to be constitutively expressed and without significant regulation by oxygen or nitrate. We discuss the stationary-phase growth...

In 25 years, drug metabolism research went from using subcellular particles of undefined content to an understanding of metabolism at the molecular level. The discoveries of cytochrome P450, enzyme induction, reactive intermediates, and genetic polymorphisms were milestones in the field. New publications from the American Society for Pharmacology and Experimental Therapeutics chronicled the dis...