[Identification of histochrome metabolism products in urine for studying drug pharmacokinetics].

Histochrome is the medicinal form of echinochrome (2,3,5,6,8-pentahydroxy-7-ethyl-1,4-naphthoquinone). The drug pharmacodynamics and its relationship with metabolism, which was revealed in previous investigations, predetermined the aim of this work: to study excretion of echinochrome and its possible metabolites in urine of rats. Histochrome was introduced to Wistar rats (n = 10) subcutaneously in a dose of 10 mg/kg. Naphthoquinone derivatives were extracted from the acidified urine by ethyl acetate and analyzed by high performance liquid chromatography with UV detection (HPLC/UV) and mass-spectrometric detection (HPLC/MS). It was established that histochrome is completely metabolized in an organism and excreted by kidneys in the form of 3-methoxy-2,5,6,8-tetrahydroxy-7-ethyl-1,4-naphthoquinone and 2-metoxy-3,5,6,8-tetrahydroxy-7-ethyl-1,4-naphthoquinone.

[Anti-lithogenic effect of meloxicam in experimental nephrolithiasis].

Experiments performed on 23 male rats, were divided into 2 groups. Animals in the control received group 1% solution of ethylene glycol (EG) as a drink during 6 weeks. In the test group, EG was also introduced for 6 weeks, and meloxicam was administered in a dose of 2.5 mg/kg from the 4th week. Every 7 days, daily urine was analyzed for the concentrations of oxalate, phosphate, and calcium and for the activity of urothelium injury marker enzymes includng lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), and N-acetyl-beta-D-glucose aminidase (NAG). In addition, sections of the rats kidney were used to detect calcium deposits by histochemical Van Koss method. The treatment of experimental nephrolithiasis by meloxicame led to simplification of pathology, as indicated by a significant reduction in the urine oxalate and calcium concentrations and a pronounced decrease in the activity of all marker enzymes (LDH, GGT, NAG).This was confirmed by morphological studies, which detected very significant reduction in both number and size of calcium deposits.

[Effects of water drinking regimens on crystallization intensity in experimental nephrolithiasis].

We studied effects of water regimens on crystallization efficacy in experimental nephrolithiasis on 3 groups of Wistar male rats with initial experimental nephrolithiasis (ethylene glycol model). The animals were on free, limited and supernormal liquid intake regimen. For 3 weeks each 3-4 days we estimated 24-h diuresis, urine concentration of calcium, phosphate and oxalate ions. After 3 weeks we made a morphological examination of the kidneys. We found that limited drinking leads to an increase in urinary concentrations of oxalate- and phosphate ions which stimulate enhanced formation of calcium-containing concrements. More water intake considerably reduces oxalate and phosphate concentrations in the urine resulting in reduction of the number and size of calcium deposits in renal tissue. Thus, low liquid intake leads to intensification of urine oversaturation causing formation of renal concrements. Much liquid intake weakens oversaturation and reduces the number and size of calcium deposits in the kidneys.

[A new technique for urinary oxalate ion determination].

The authors propose a technique for the determination of urinary oxalate ions by high performance liquid chromatography, which may be used for clinical and scientific purposes.

[Features of the pharmacodynamics and pharmacokinetics of furosemide upon long-term administration in rats].

Long-term administration of furosemide in rats (single daily dose, 20 mg/kg for 7 days) was accompanied by a decrease in the diuretic, natriuretic, and kaliuretic effects, which was related to a decrease in the rate of renal metabolism and excretion. It was found that more than 85% of the daily excretion of sodium takes place within the first 6 h after furosemide administration (on the background of comparable excretion of the drug), while the elimination of potassium and water during one day is more uniform. It is established that the long-term administration of furosemide leads to a decrease in the drug excretion during the first 6-h period, followed by a growth in the subsequent 18-h period of time. These changes in the daily dynamics of drug excretion account for the analogous trends in the elimination of water and electrolytes.

[The chemico-pharmacological patterns in the action of plants from the family of Pyrolaceae]. / Khimiko-farmakologicheskie zakonomernosti v deistvii semeistva grushankovykh.

The effect of leaf decoctions of three plants of the Pyrolaceae family, namely, umbrella wintergreen, one-side ortilia, and round-leaf Pyrola was studied in rat experiments. All plants under study were found to contain approximately equal amounts of tannins and arbutin glycoside. Their concentration was comparable though rather lower than in common bearberry, a well-known plant with diuretic and antiseptic activity. When given for a long time, all Pyrolaceae increased urination and sodium excretion. Besides, their decoctions caused an antimicrobial effect. Only round-leaf Pyrola weakened the development of experimental inflammation. Its anti-inflammatory effect was probably due the presence of flavonoids the content of which in Pyrola was maximum.

[The mechanism of the diuretic action of the preparation polyosm]. / Mekhanizm diureticheskogo deistviia preparata poliosm.

The mechanism of the diuretic effect of the new drug polyosm, polyethylene oxide 400 solution, was studied in experiments on anesthetized cats. Intravenous polyosm infusion was attended with a marked diuretic and natriuretic effect developing due to reduced reabsorption of water and natrium and increased glomerular filtration.

[The effect of calcium antagonists on the development of inflammatory edema in rats]. / Vliianie antagonistov kal'tsiia na razvitie vospalitel'nogo oteka u krys.

The calcium antagonists verapamil and nifedipine were shown to attenuate the development of carrageenin-induced rat paw inflammatory edema. Oral nifedipine exerted more pronounced antiedematous dose-dependent effects.

[Comparative effectiveness of the anti-inflammatory action of diuretics and butadione in an experiment]. / Sravnitel'naia éffektivnost' protivovospalitel'nogo deistviia diuretikov i butadiona v éksperimente.

Dichlothiazide and butadione were shown to attenuate equally the development of the rat paw inflammatory edema induced by subplantar dextran administration. Ethacrynic acid produced more pronounced antiedematous effect. Also, ethacrynic acid reduced to the highest degree the damp and dry mass of the inflammatory granuloma. Oxadoline and butadione considerably inhibit the formation of granuloma as well. The combined use of diuretics and butadione did not lead to a mutual potentiation of the antiinflammatory effect in exudative and proliferative inflammation.

[Effect of diuretics on vascular permeability and proliferative inflammation in rats]. / Vliianie diuretikov na sosudistuiu pronitsaemost' i proliferativnoe vospalenie u krys.

It is shown that ethacrynic acid and dichlothiazide in 50 mg/kg dose reduce the dextran-induced increase of rat skin vascular permeability. Besides, durable administration of furosemide, dichlothiazide and ethacrynic acid in 50-80 mg/kg doses decreases the dry mass of inflammatory granuloma. This fact shows the ability of diuretics to suppress the development of proliferative inflammation.

[Effect of diuretics on the development of experimental inflammatory edema in rats]. / Vliianie diuretikov na razvitie éksperimental'nogo vospalitel'nogo oteka u krys.

Experiments on rats have shown that administration of furosemide, dichlothiazide and etacrinic acid (50 mg/kg intraperitoneally) reduced the development of experimental inflammatory edema caused by subplantar administration of 0.1 ml of 6% dextran or 10% ovalbumin. The antiedematous effect of the diuretics was preserved under the conditions of bilateral nephrectomy, which points to the presence of extrarenal mechanisms in the action of the drugs in experimental inflammation.

[Effect of dichlothiazide on the transport of organic substances in the kidneys]. / Vliianie dikhlotiazida na transport organicheskikh veshchestv v pochkakh.

Following a protracted introduction of dichlothiazide to rats (20 mg/kg) and to dogs (5 mg/kg) there occurs a marked increase in the tubular secretion of the cardiotrast and passage of urates with urine. A single and long-term administration of the drug to dogs did not have any substantial effect on the maximal reabsorption of glucose.

[Effect of furosemide on the transport of organic substances in the kidneys]. / Vliianie furosemida na transport organicheskikh veshchestv v pochkakh.

The influence of furosemide on the maximal glucose reabsorption, cardiotrast secretion and urate excretion was studied in chronic experiment. Single injection of furosemide increased the maximal glucose reabsorption in dogs. Thesere was no alteration in the secretory cardiotrast transport in response to the drug administration. Furosemide administration produced an uricosuric action in dogs and rats.

[Interaction of renal transport of cardiotrast, glucose and urates in dogs]. / Vzaimodeistvie pochechnogo transporta kardiotrasta, gliukozy i uratov u sobak

Interaction of renal cardiotrast, glucose and urate transport was investigated in dogs in chronic experiments. There was no alteration in the maximum secretion of cardiotrast and in the malximum glucose reabsorption during simultaneous injection of cardiotrast and glucose. It was also shown that with the maximum saturation of the renal secretory and reabsorption transport there was no significant change in the urate excretion. The data obtained pointed to a possibility of combined administration of cardiotrast and glucose solutions with simultaneous determination of values of maximum cardiotrast secretion, maximum glucose reabsorption and urate excretion.