Showing papers in "Biochemical Pharmacology in 1966"

TL;DR: The accumulation of alloxanthine during prolonged therapy with allopurinol may contribute significantly to the therapeutic effects of the drug in the control of hyperuricemias.

TL;DR: The results may be of importance in studies with such compounds as epinephrine, 5-hydroxytryptamine, choline, histamine, and ethanol, among others, since all of these substances can be converted, in vivo , to aldehydes that may undergo further oxidation.

TL;DR: Human erythrocytes are protected or stabilized against hypotonic and mechanical hemolysis in the presence of low concentrations of many phenothiazines, reserpine, and haloperidol and the decrease in osmotic fragility may be explained possibly by an expansion of the cell membrane.

TL;DR: Different regional differences in the subcellular distribution of labeled dopamine and norepinephrine were observed after the injection of 3 H-dopamine, and endogenous dopamine was predominantly recovered in the supernatant fraction, but exogenous 3H-Dopamine or3 H-norpinephrine was found mainly in the particulate fraction.

TL;DR: The time courses of changes in brain content of γ-aminobutyric acid (γABA) and sensitivity to electroconvulsive shock were studied in mice after administration of amino-oxyacetic acid (AOAA) and it is suggested that soon after γABA-transaminase blockade with AOAA the increased levels of ΓABA may, indeed, decrease neuronal excitability.

TL;DR: Measurements of the circumferences of the erythrocyte profiles from electron micrographs indicate that 1.4 × 10−5M prochlorperazine induces a membraneexpansion of around 19 per cent, compatible with an intramembrane location of the 108 molecules per cell that is known to occur (from adsorption studies).

TL;DR: The metabolic fate of cytosine-2 14 C in the rat paralleled that of its antimetabolite in that significant degradation followed only its administration by the oral route, and in man, after oral doses, no metabolic degradation of 5-FC- 2 14 C occurred.

TL;DR: Although administration of cytosine arabinoside at therapeutic levels depressed the ability of leukemic leukocytes to incorporate cytidine into DNA in vitro, there was no correlation between the degree and duration of this effect and the clinical response to the drug.

TL;DR: In this paper, the distribution and metabolism of the central nervous system depressants, γ-butyrolactone and γhydroxybutyric acid, have been investigated.

TL;DR: The high DOPA decarboxylase activity in the gastric mucosa of the species studied may indicate an important role for this enzyme in gastric function.

TL;DR: It has now been shown that cysteine itself accounts for at least 90 per cent of the accumulating thiol after Cysteine injection, which indicates the relevance of the increased thiol concentration to mechanisms of protection against the toxicity of alkylating agents.

TL;DR: Ethanol alone produced small decreases in rat and rabbit brain norepinephrine and 5-hydroxytryptamine concentrations that were no greater than the effects of intraperitoneal injections of similar volumes of isotonic saline but increased acetaldehyde blood levels produced by disulfiram pretreatment before the ethanol doses or by the administration of acetaldehyde itself caused statistically significant decreases in brain NE but no further effects on 5-HT.

TL;DR: Histidine decarboxylases from fetal rat tissue and from gastric tissue were found to be stereospecific for l -histidine and not inhibited by high concentrations of histamine.

TL;DR: Evidence is presented to indicate that the activity of Ethyl chlorophenoxyisobutyrate is derived from its binding to a specific fraction of the plasma protein, thereby causing a redistribution of endogenous hormones and cofactors into the liver, principally thyroxine.

TL;DR: The nature of the processes whereby the mobilization of free fatty acids (FFA) is regulated by the sympathetic nervous system was examined from the lipolytic responses of isolated fat cells from rat epididymal adipose tissue, and direct evidence shows that cyclic 3',5'-AMP can increase lipolysis in intact fat cells.

TL;DR: Two progestational steroids, norethynodrel and progesterone, have been compared in their effects on hepatic drug-metabolizing enzyme systems in vitro and both agents were capable of inhibiting the metabolism in vitro of these drug substrates.

TL;DR: Oral administration of cysteine or acetylcysteine to rats or dogs produced little change in blood or tissue sulfhydryl levels, and only a small increase in urinary sulfHydryl compounds.

TL;DR: It is suggested that a correlation may exist between the carcinogenicity of polycyclic hydrocarbons and their induction of the hepatic microsomal enzyme responsible for the 2-hydroxylation of biphenyl.

TL;DR: Whether a membrane lysin does or does not in low concentrations cause a prolonged and steady membrane stabilization may be a simple possible criterion for distinguishing between specific and nonspecific lysins.

TL;DR: Ferrioxamine was not degraded to any appreciable extent in nephrectomized dogs: after a large dose the plasma concentration fell very slowly—probably as a consequence of biliary excretion, and the volume of distribution of ferrioxamines was equal to thevolume of the extracellular compartment.

TL;DR: It is suggested that increased SAMe utilization is the important factor in the lowering of tissue SAMe by pyrogallol, purpurogallin, and pargyline.

TL;DR: Results showed that GABA metabolism was much slower than succinic semialdehyde oxidation, indicating that in vivo transamination is probably rate limiting with respect to GABA degradation, and no evidence was obtained that exogenous GABA penetrated into the central nervous system under these conditions.

TL;DR: All ten hitherto described metabolites of imipramine were found to be formed in the rat, nine of them in vitro, and relative conversion rates for the metabolic pathways were estimated.

TL;DR: Comparison of results with findings in vivo provide evidence for the existence of two amine concentrating mechanisms: a relatively nonspecific mechanism in the neuronal membrane, which is blocked by a variety of drugs; and an intracellular mechanism of higher specificity which is block by reserpine or tetrabenazine.

TL;DR: It is suggested that steroids interact with artificial lipid spherules to produce changes in their permeability which resemble steroidinduced changes in natural membranes, most likely by provoking a structural rearrangement of lipid layers.