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At least 19 recordsLinked to original sources
PubMed1977

Inhibition of C1s-induced vascular leakage in guinea pigs by substituted benzamidine and pyridinium compounds.

A variety of benzamidine and pyridinium compounds were examined for their ability to inhibit irreversibly C1s-induced vascular leakage in guinea pig skin. Vascular leakage was compared with esterolysis of N-Z-L-Tyr-Np and catalysis of EAC42 formation by C1s. Vascular leakage correlated significantly better with esterolytic activity than with EAC42 formation. The presence of a sulfonyl fluoride moiety in the compounds is important in the inhibition of C1s-induced vascular leakage.

Amidines↗
PubMed1975

Clinical neuromuscular pharmacology of AH 8165 D, an azobis-arylimidazo-pyridinium-compound.

The neuromuscular blocking properties of AH 8165 D (1,1'azobis-(3-methyl-2-phenyl-1H-imidazo-1,2a-pyridinium)dibromide) were quantitatively studied in 50 patients, undergoing extra-abdominal surgery and anaesthetized with barbiturates, nitrous oxide, fentanyl and droperidol, by means of mechanograms of the hand muscles obtained by ulnar nerve stimulation. AH 8165 D is a rapid-acting nondepolarizing agent (full effect within 1--2 min) providing good intubation conditions similar to those obtained with suxamethonium. AH 8165 D may be considered to be indicated for emergency intubation in patients with full stomach when the risk of regurgitation is high. The duration of action of clinically useful doses (0.4-0.8 mg/kg body weight) is shorter than that of equi-effective doses of other nondepolarizing muscle relaxants. Repeated doses show a cumulative effect. The neuromuscular blockade can easily be reversed by an anticholinesterase drug. AH 8165 D-induced muscle relaxation is always accompanied by a dose-dependent tachycardia limiting the clinical usefulness of this new drug.

Adult↗
PubMed1992

Identification of novel reduced pyridinium derivatives as synthetic co-factors for the enzyme DT diaphorase (NAD(P)H dehydrogenase (quinone), EC 1.6.99.2).

The enzyme DT diaphorase (NAD(P)H dehydrogenase (quinone), EC 1.6.99.2) is unusual in that it can utilize either NADH or NADPH as a co-factor for the reduction of its substrates. We have shown that the intact NAD(P)H molecule is not required and that other reduced pyridinium compounds can also act as co-factors for DT diaphorase. The entire adenine dinucleotide portion of NAD(P)H can be dispensed with entirely and the simplest quaternary (and therefore reducible) derivative of nicotinamide, 1-methylnicotinamide, was as effective as NAD(P)H as a co-factor for the reduction of the quinone, menadione. Nicotinamide 5'-O-benzoyl riboside was also as effective a co-factor as NAD(P)H, whilst nicotinamide ribotide and riboside have a higher Km, and decreased the kcat of DT diaphorase. Nicotinic acid derivatives had little activity. Kinetic analysis indicated that both nicotinamide ribotide and riboside may be interacting with the menadione binding site rather than the NAD(P)H site. Irrespective of the differences between the various reduced pyridinium derivatives in their ability to act as co-factors for the reduction of menadione by DT diaphorase, all the compounds that showed activity in this assay were equally effective co-factors for the reduction of the nitrobenzamide, CB 1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide). The apparent Km of DT diaphorase for all these co-factors approached zero. It was concluded that co-factor binding is not a rate-limiting step in the nitroreductase activity of DT diaphorase.

Animals↗
PubMed1977

Introduction of new crosslinks into proteins.

Analysis of the crosslinks epsilon-(gamma-glutamyl) lysine and epsilon- (beta-aspartyl) lysine present in treated wool has been improved by modifying the enzymic digestion. Treatment of wool with either monocarboxylic acid chlorides in dimethylsulfoxide or with 1-fluoro-2,4-dinitrobenzene in the presence of acetate considerably decreased epsilon-amino groups and solubility. Since no information of interchain amide crosslinks was observed, the hypothesis of so-called self-crosslinking postulated by ZAHN has to be withdrawn. The effects of both treatments are explained in the light of new results. The reaction of wool with glutaraldehyde leads to a stabilization of the fiber. Experiments with glutaraldehyde and primary alkyl amines as model componds revealed that the cyclic form of the aldehyde gave the unstable N-alkyl-2,6-dihydroxypiperidine, which either looses water to give N-alkyldihydropyridine or condenses with 2,6-dihydroxytetrahydropyran to yield a copolyether which was isolated. According to recent publications, crosslinking of proteins by glutaraldehyde is due to the formation of quaternary pyridinium compounds.

Amino Acids↗
PubMed1978

Aging of soman-inhibited acetylcholinesterase: inhibitors and accelerators.

The influence of 27 possible effectors, mostly bispyridinium salts, upon the dealkylation (aging) of soman-inhibited acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7) was examined at pH 7.6 and 25 degrees C. In the absence of effectors, the rate constant of the aging process was 4.0. 10(-2) min-1. At 2 mM, the strongest inhibitor reduced the rate to 0.8. 10(-2) min-1, whereas it was raised to 8.2. 10(-2) min-1 by the most potent accelerator.

Acetylcholinesterase↗
PubMed1979

Ganglion blocking properties of some bispyridinium soman antagonists.

Various doses of several bispyridinium compounds (HS-6, HI-6, HGG-12, HGG-42, and SAD-128) known to protect animals against the irreversible cholinesterase inhibitor soman were examined to determine their effects on the cardiovascular and respiratory system of cats. Although the potency varied considerably all of the compounds tested lowered the blood pressure, which appeared to be the result of ganglion blocking properties as determined by their reduction of the pressor response to dimethylphenylpiperazinium and the blockage of the contraction of the preganglionically stimulated cat nictitating membrane. Some of the compounds caused cessation of respiration at much lower doses than others but did so at doses greater than those causing ganglion blockage.

Animals↗
PubMed1975

Ion-exclusion chromatography of compounds of biological interest.

The principle of ion exclusion was examined as a method for the separation of small ionic compounds. The systems employed consisted of very porous column packings, substituted with fixed charges, which were eluted by buffer solutions of low ionic strength. DEAE-Sephadex A-50 was principally employed, and it was shown that there was a linear relationship between the net charge on a cation and its partition coefficient into the gel phase. A similar relationship existed in the chromatography of amino acids on various columns bearing fixed negative charges. It was concluded that this was an efficient form of chromatography, which gave results directly related to the ionic charge of the sample being examined. The charge characteristics of biologically active compound could be determined by this method.

Chromatography, DEAE-Cellulose↗
PubMed1992

Design, synthesis, and biological evaluation of novel 4-substituted 1-methyl-1,2,3,6-tetrahydropyridine analogs of MPTP.

The exceptionally good MAO-B substrate properties of several 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) derivatives have prompted studies to evaluate the corresponding properties of tetrahydropyridines bearing heteroatom-linked groups at C-4. The 1-methyl-4-phenoxy-1,2,3,6-tetrahydropyridine analog proved to be an excellent MAO-B substrate. Unlike analogs bearing hydrocarbon substituents at C-4, the resulting dihydropyridinium metabolite did not undergo further oxidation to the pyridinium compound but rather underwent hydrolytic cleavage. This observation has led to studies designed to explore the possibility of developing novel, nontoxic derivatives of MPTP bearing potential pharmacologically active leaving groups at C-4. In this paper we report the results of synthetic and metabolic studies on a series of tetrahydropyridine analogs of MPTP with oxygen, sulfur, and carbamoyloxy derivatives on C-4 which serve as model compounds to evaluate the scope of this prodrug concept.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1992

The neurotoxin 1-methyl-4-phenylpyridinium: a selective cytostatic agent in small-cell lung cancer cell lines with neuroendocrine properties.

BACKGROUND: Small-cell lung cancer (SCLC) is a common malignancy that is usually fatal, since it metastasizes and recurs even after aggressive chemotherapy. While the cellular origin of this cancer is not well established, the cells of certain tumors exhibit neuroendocrine markers, including L-dopa decarboxylase. PURPOSE: We designed in vitro and in vivo studies to investigate whether the neuroendocrine features in classic SCLC cell lines were sufficient to make them sensitive to 1-methyl-4-phenylpyridinium (MPP+), a known neurotoxin that destroys nigrostriatal dopaminergic neurons. METHODS: Both classic SCLC cell lines (NCI-H345, NCI-H510, NCI-H187, and NCI-H146) and variant SCLC cell lines (NCI-H417, NCI-H82, NCI-H446, and NCI-H524) were exposed to MPP+ (0-512 microM) for 3 days. Inhibition of DNA synthesis was determined by [3H]thymidine incorporation assays. In a related experiment, MPP+ was removed from the classic cell line culture, and the incorporation of [3H]thymidine was determined. In the in vivo study, male athymic nude mice received subcutaneous injections of 0.5 mL tumor cells with matrigel for 10 days to enhance tumor growth, followed by MPP+ at doses of 100-400 micrograms/d given intraperitoneally for 2 days. RESULTS: All four classic SCLC cell lines showed great sensitivity to MPP+, with detachment from laminin substrates and inhibition of DNA synthesis. MPP+ interfered with [3H]thymidine incorporation and, thus, with DNA synthesis in classic SCLC cell lines at low doses (median +/- SD, 12 +/- 4 microM), whereas much higher doses (median, > 512 microM) were required to inhibit [3H]thymidine incorporation in the variant lines. Treated cells excluded trypan blue dye, showing that inhibition of DNA synthesis was not due to cytotoxicity, and the cells incorporated [3H]thymidine when MPP+ was removed from the culture medium, demonstrating that the inhibition was reversible. MPP+ inhibited the growth of the classic NCI-H187 and variant NCI-H417 cell lines implanted in nude mice. CONCLUSIONS: These results suggest that MPP+ differentially interferes with DNA synthesis in SCLC cell lines in vitro; the selective inhibitory effect on classic cell lines suggests that the neuroendocrine properties expressed by classic SCLC cells may be responsible for the differential effect. IMPLICATIONS: MPP+ exerts a cytostatic effect on these cell lines, and the differential sensitivity observed in vitro is maintained in vivo, suggesting that MPP+ or other pyridinium compounds may be of therapeutic value in SCLC.

1-Methyl-4-phenylpyridinium↗
PubMed1979

Therapeutic effects of the bis-pyridinium salts HGG-12, HGG-42, and atropine, benactyzine in organophosphate poisoning of dogs.

Therapeutic properties of various combinations of the bispyridinium salts HGG-12 and HGG-42 against soman and sarin poisoning were investigated in male beagles. Best therapeutic efficiency was shown by HGG-42 in a dosage of 30 muMol/kg. Also good effects were produced by the combination of both oximes in a low dosage of 3 muMol/kg for each one. In soman poisoning no significant reactivation of cholinesterase in serum or erythrocytes was observed.

Animals↗
PubMedDate not supplied

[The results of a clinical trial of the new drug agent carbabenzpyride].

Analyzed were results of a clinical use of a new drug carbabanzpyrid in 57 patients as an analgetic, antipyretic, anti-inflammatory, interferonogenic drug. The drug proved effective in the complex treatment of several diseases, accompanied by fever, pain syndromes of different genesis and location, acute respiratory viral infections, active inflammatory processes of different etiology including bronchitis, pneumonia, active rheumatism, arthralgias, myalgias. The drug was of little efficacy in infections-allergic polyarthritis with a marked exudative component.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1976

Irreversible enzyme inhibitors. Inhibitors of guinea pig complement derived by quaternization of substituted pyridines with benzyl halides.

A series of 83 compounds derived from hydrocarbon-substituted pyridines by quaternization with PhCH2Br usually containing a 2-SO2F or 6-Cl-2-SO2F group was synthesized and evaluated as inhibitors of guinea pig complement and in most cases its C1 component. The most active compounds were 3-(4-phenylphenylbutyl)-N-(6-choro-2-fluorosulfonylbenzyl) pyridinium bromide (43) and 3-(4-phenylphenylbutyl)-N-(2-fluorosulfonylbenzyl) pyridinium bromide (44), each showing 50% inhibition at 7.8 muM. The most effective irreversible inhibitor of the C1 component was N-(6-chloro-2-fluorosulfonylbenzyl)-5,6-benzoquinolinium bromide (87), which showed 50% inhibition at 4 muM.

Animals↗
PubMed1977

Rabbit endothelial response to ophthalmic preservatives.

The endothelial surface of isolated rabbit corneas were perfused for three hours with varying concentrations of benzalkonium chloride and cetylpyridinium chloride. The threshold for physiological and ultrastructural alteration of corneal endothelium is approximately 0.0001% for benzalkonium chloride and 0.01 mM for cetylpyridinium chloride. The effects of the surfactants can be induced with as little as a 15-minute exposure without subsequent recovery. Use of ophthalmic medications or irrigating solutions containing these agents inside the eye is potentially hazardous to the corneal endothelium. Topical administration of 0.133% benzalkonium chloride to the anterior surface of deepithelialized in vivo corneas (five doses, seven minutes apart) caused no alterations of corneal endothelial cell function or ultrastructure.

Animals↗
PubMed1978

Binding of dyes to hydroxyapatite treated with cetylpyridinium chloride or cetrimonium bromide.

The effect of cetylpyridinium chloride (CPC) and cetrimonium bromide (CTAB) on the adsorption of some acidic food dyes to hydroxyapatite was studied. The dyes investigated were brilliant blue (FD&C Blue No. 1), tartrazine (FD&C Yellow No. 5), sunset yellow (FD&C Yellow No. 6) and amaranth (FD&C Red No. 2). The apatite had adsorbed 9.2 mumol CPC per g dry weight. The adsorbed CPC was in equilibrium with a free concentration of 20 microgram/ml (58 micrometer). The adsorption of CPC and CTAB to the apatite was followed by an increased ability of the crystals to bind the dyes. The dyes were very firmly adsorbed and were not released during a series of washings. Untreated apatite showed only a minor affinity for the dyes. The adsorbed dyes were easily washed out. CPC and CTAB showed the smae specific ability to increase the binding capacity of the apatite. The results are discussed and related to the formation of stains on the teeth in persons using quaternary ammonium compounds for mouthrinsing. A mechanism explaining the production of stains is proposed.

Adsorption↗