Showing papers in "Biochemical Pharmacology in 1974"

TL;DR: It appeared that, of the known metabolites of cyclophosphamide, only phosphoramide mustard possesses the cytoxicity and biological half-life appropriate to the active antitumour metabolite, and four other metabolites of low cytotoxicity were isolated and identified.

TL;DR: The effects of hydrogen-ion concentration on enzyme activity are consistent with the view that unprotonated amines are the species which bind to the enzyme, and led to formulation of a proposed mechanism of dehydrogenation which does not depend upon intermediate formation of Schiff base from the substrate amine.

TL;DR: It is unlikely that the ability of cis and trans Pt(IV)diammine tetrachloride to cross-link isolated or cellular DNA bears any relationship to their cytotoxic properties, and it is concluded that the differences seen in vitro and in vivo were approximately the same.

TL;DR: Inhibition of nucleic acid synthesis was demonstrated in both this and other drug-sensitive organisms at drug concentrations as low as 1 μg/ml and a possible mechanism of action of the drug has been postulated.

TL;DR: A miniaturized method for the assay of serotonin, noradrenaline and dopamine in extracts from l.5 to 5 mg of brain tissue (rat and mouse) was developed and permitted quantification and spectral analysis of pmole amounts of the amines.

TL;DR: Intraperitoneal injection of adenosine into Swiss albino mice, RB strain, sensitive to audiogenic convulsions, rapidly produces sedation, modification of the EEG, lowering of arterial pressure and protection against audiogenic seizures.

TL;DR: There was a large, reversible inhibition of glutamate decarboxylase activity in the brain and levels of aspartate and taurine decreased significantly in all the brain regions investigated during convulsions.

TL;DR: Regression analyses clearly establish that both activity patterns in vitro and in vivo can be satisfactorily described by linear equations in terms of the hydrophobic bonding constant indicating a close correlation between biological activity and lipophilic character.

TL;DR: 4-Aminocatechol, an abnormal metabolite of phenacetin suspected of causing kidney damage, gave normal results for enzyme excretion suggesting the absence of renal lesions in the rat.

TL;DR: In this paper, the effects of cis and trans Pt(II)-diammine dichloride on the colony forming ability of HeLa cells have been measured, showing that more of the trans compound was bound to DNA than cis when cell survival was reduced by the same amount, suggesting there was a real difference in the mechanisms of action of the two isomers.

TL;DR: At the pH optimum for the flavoprotein mixed-function oxidase, virtually all of the methimazole metabolized by homogenates of pig liver appears to be catalyzed by this membrane-bound oxidase.

TL;DR: The concentration of warfarin required to inhibit the reductase in vitro was similar in control and resistant rats to the concentration ofwarfarin in vivo during inhibition of prothrombin formation.

TL;DR: Although SKF 525-A markedly decreased the liver necrosis and the rise in serum isocitrate dehydrogenase (ICD) caused by CCl 4, it only partially prevented the CCl4 -induced decrease in body temperature.

TL;DR: The correlation between the anticholinesterase activity and the CNS activity as well as the structural relation of the drugs to agonists and antagonists of the cholinergic system is discussed.

TL;DR: The data presented indicate that at low concentrations, miconazole acts primarily on the yeast cell membranes resulting in a selective inhibition of the uptake of precursors of RNA and DNA (purines) and mucopolysaccharide (glutamine).

TL;DR: Modified methods for measurement of cytochrome P-450 content of liver homogenates, and of formaldehyde produced in demethylation reactions are described and it is suggested that the amount of toxic metabolite is more important than the rate at which it is formed.

TL;DR: Microsomal nitroreductase activity paralleled NADPH-cytochrome c reductase activity in rats pretreated with allylisopropylacetamide (AIA), phenobarbital or 3-methylcholanthrene (3-MC), but did not parallel the level of microsomal cytochrome P-450.

TL;DR: It is suggested that the centrally stimulating component of nomifensine is based upon its strong inhibition of catecholamine re-uptake into noradrenergic as well as dopaminergic nerve endings, which is lacking in most thymoleptic drugs.

TL;DR: The structure-affinity relationships of various 19-nor spirolactones show greater, equivalent or lesser affinity vis-a-vis their parent compounds should define one of the determinants of pharmacologic activity.

TL;DR: Under the conditions of the experiments described in this report, the binding of sulfur to microsomes decreases the concentration of cytochrome P-450 in the microsome and inhibits slightly the rate of the mixed-function oxidase-catalyzed metabolism of benzphetamine.