ascorbic-acid and potassium-carbonate

The present studies report on the significance of L-ascorbic acid (AA) and urinary electrolytes for promotion of rat urinary bladder carcinogenesis. Male F344 rats were given an oral administration of 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) as an initiator for 4 weeks, and were then subjected to treatment with dietary supplements of test chemicals for 32 weeks. Administration of 5% sodium L-ascorbate (SA), the sodium ion form of AA significantly promoted urinary bladder carcinogenesis, whereas administration of 5% AA did not. The urine of rats given SA but not AA was characterized by an apparent elevation of pH, an increase of sodium ion concentration, and increases in the urinary content of total AA and its metabolite, dehydroascorbic acid. Administration of 3% NaHCO3, which induced elevation of pH and increase of sodium ion concentration in the urine, promoted BBN bladder carcinogenesis. When rats were given 5% AA plus 3% NaHCO3, AA enhanced the promoting activity of NaHCO3. Lowering of pH by 1% NH4Cl clearly reduced the promoting activity of 5% SA when these two compounds were given concurrently. Treatment with 5% AA plus 3% K2CO3 promoted BBN bladder carcinogenesis in rats, whereas addition of 5% CaCO3 or 5% MgCO3 to AA did not. These results strongly indicate the important role of urinary sodium or potassium ion concentration and pH in modulating urinary bladder carcinogenesis by AA.

Topics: Animals; Ascorbic Acid; Bicarbonates; Butylhydroxybutylnitrosamine; Carbonates; Electrolytes; Hydrogen-Ion Concentration; Male; Potassium; Rats; Rats, Inbred F344; Sodium; Sodium Bicarbonate; Urinary Bladder Neoplasms; Urine

A series of 5H-dibenz[b,f]azepine containing different aminophenols and substituted aminophenols were synthesized. 3-chloro-1-(5H-dibenz[b,f]azepine-5yl)propan-1-one (2) was obtained by N-acylation of 5H-dibenz[b,f]azepine (1) with 3-chloro propionyl chloride. Further base condensation with different aminophenols and substituted aminophenols to produce series of 5H-dibenz[b,f]azepine containing aminophenol and substituted aminophenol (2a-e). The structures of newly synthesized compounds were characterized by spectral and elemental analysis. Their antioxidant properties were evaluated by using several methods: scavenging effects on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, inhibition of lipid peroxidation using beta-carotene linoleate system, inhibition of human low-density lipoprotein (LDL) oxidation and reducing power. Butylated Hydroxy Anisole (BHA) and Ascorbic acid (AA) were used as the reference antioxidant compounds and also the comparative study with the synthesized compounds was done. Under our experimental conditions, Compound (2) showed negligible activity over all the antioxidant assays but 5H-dibenz[b,f]azepine containing different aminophenols and substituted aminophenols (2a-e) showed good antioxidant activities over all the methods and compounds containing substituted aminophenols 2e and 2d showed predominant antioxidant activities among the synthesized analogues.

Topics: Adult; Aminophenols; beta Carotene; Biphenyl Compounds; Carbonates; Dibenzazepines; Free Radical Scavengers; Humans; Lipid Peroxidation; Lipoproteins, LDL; Oxidation-Reduction; Picrates; Potassium

The dose dependence of K2CO3 promotion of two-stage urinary bladder carcinogenesis and the amplifying effects of additional L-ascorbic acid (AsA) administration were investigated. Male F344 rats were given 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine in their drinking water for 4 weeks and then fed basal diet containing K2CO3 at levels of 0, 1, 1.5, 2.2, and 3% with or without 5% AsA or 3% NaHCO3 supplementation from weeks 5 to 8 (4 weeks) and weeks 12 to 20 (9 weeks). During weeks 9 to 11 (3 weeks), the rats were fed 3% uracil in their diet. For controls, rats without N-butyl-N-(4-hydroxybutyl)nitrosamine treatment were given either 3% K2CO3, 5% AsA, or both plus the uracil treatment. The total observation period was 20 weeks. K2CO3 dose dependently increased the numbers of the putative preneoplastic lesion, papillary or nodular hyperplasia, and papillomas in rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine. AsA (5%), while itself exerting no promoting effect, amplified the enhancing influence of K2CO3 on the induction of papillary or nodular hyperplasia and papillomas. The dose-dependent elevation of urinary pH and K+ concentration was associated with K2CO3 treatment with or without AsA. Thus, increased urinary pH and K+ concentration appear to play important roles in K2CO3 promotion, and AsA amplifies this promotion.

Topics: Animals; Ascorbic Acid; Body Weight; Carbonates; Carcinoma; Drug Synergism; Hyperplasia; Male; Organ Size; Papilloma; Potassium; Rats; Rats, Inbred F344; Reference Values; Urinary Bladder; Urinary Bladder Neoplasms

In this paper a method of semiquantitative cysteine determination is presented, which is based on the formation of a red cysteine-Na-nitroprusside salt. The method is a suitable rapid test for checking the process of ascorbic acid therapy in cystinuria and cystine urolithiasis patients. It guarantees acceptable reproducibility of values and can be easily carried out in every clinicochemical laboratory. With the K2CO3/nitroprusside test described and an additional cystine rapid test (Ni2+/S2O4(2-) tablet reagency) a separate semiquantitative differentiation of cysteine and cystine in fresh (!) urine is possible.

Topics: Ascorbic Acid; Carbonates; Cysteine; Cystinuria; Ferricyanides; Humans; Nitroprusside; Potassium; Urinary Calculi