Increase In Uric Acid Excretion Research Articles

Метаболические факторы риска и формирование мочевых камней. Исследование VII: Литогенные свойства урикозурии у мужчин и женщин.

Introduction. Hyperuricosuria usually considered as the main metabolic factor in the formation of uric acid stones, but this issue remains unclear. Gender differences in the prevalence of urolithiasis (UL) indicate the need for a more detailed study of the lithogenic properties of uricosuria and its role in the development of various metabolic types of UL. In this study, was investigated the effect of varying degrees of uricosuria in men and women with UL on metabolic parameters and the frequency of detection of urinary stones of different chemical composition. Materials and methods. A total of 982 patientsа with UL (439 men and 543 women aged 18 to 79 years)were examined. To assess the lithogenic activity of uricosuria in men and women with UL, the values of uric acid excretion (in mmol/day) were ranked in ascending order and divided into 10 equal parts (ten 10%-х percentilesей). In each of the ranges, the percentage distribution of types of urinary stones and biochemical parameters of urine and blood were determined. Results. As the degree of uricosuria increased from minimum to maximum values in men and women, there were no differences in the percentage distribution of uric acid stones. The different orientation of the processes of urate lithogenesis is noted, which was manifested in uricosuria above 3.48 mM/day by the accumulation of anhydrous uric acid in the stones in women 1.47 times greater than in men, in whom the proportion of uric acid in the stones, on the contrary, decreased by 1.36 times. It was found that uricosuria above 3.48 mM/day was accompanied by activation of oxalate lithogenesis rather than uric acid: the incidence of oxalate stones in men increased by 1.55 times (p=0.0025), and in women by 2.16 times (p=0.0013). At the same time, the proportions of the oxalate component in the stones of male and female patients, respectively, increased, mainly due to the wevellite component. An increase in uric acid excretion over 3.48 mM/day led to a relative decrease in the frequency of detection of carbonatapatite stones in men by 1.85 times (p=0.0104), and in women by 2.0 times (p=0.0153). With increasing uricosuria, both men and women experienced an almost linear increase in the levels of calcium, phosphate, and magnesium excretion (p<0.0001). The blood phosphate content in women was on average 7-11. 6% higher than in men, and uric acid was lower by 8.5-16.0% for almost all values of uricosuria. Calcemia levels in men and women did not have statistically significant differences. for all values of uricosuria. Men in the age groups from 30-39yr to 60-79yr have a higher uric acid excretion than women, which also corresponds to a higher incidence of oxalate stones in men, exceeding this indicator in women in all age groups by 2.5 -1.8 times (p<0.05). The formation of uric acid stones is observed in men of an earlier age than in women, namely from the age of 18-29yr, while in women the formation of stones of this type is detected only from the age group of 40-49yr and older. Conclusion. Characteristic property of uricosuria of various degrees is its different ability to influence the dynamics of metabolic parameters of excretion and lithogenesis of calcium stones (oxalate and phosphate stones) in men and women in the absence of a noticeable effect on the lithogenesis of uric acid stones, which should be taken into account when conducting personalized metaphylaxis of urolithiasis.

Physico-biochemical parameters of urine and blood and biominerology of urinary bladder stones in patients with bladder outlet obstruction

BACKGROUND: Bladder outlet obstruction is one of the main factors leading to the formation of stones in the urinary bladder. Understanding of the physico-biochemical processes in urine and blood, as well as the biomineralogy of urinary bladder stones, will make it possible to determine the pathogenetically justified treatment of such patients.
 AIM: The aim of the study was to identify and study the relationship between the physico-biochemical parameters of urine and blood and the biomineralogical composition of urinary bladder stones in patients with bladder outlet obstruction.
 MATERIALS AND METHODS: A comprehensive examination of 76 patients at the age of 37 to 89 years with urinary bladder stones occurred against the background of bladder outlet obstruction was carried out. A comprehensive diagnosis, including an assessment of the physico-biochemical parameters of urine and blood, bacteriological urine tests, radiological diagnostics, as well as biomineralogical studies of concretions, was carried out.
 RESULTS: The data obtained show that not all physicochemical parameters of blood and urine of the subjects are comparable with the data of patients with nephrolithiasis. In the vast majority of the studied kidney calculi were not detected, in addition, blood biochemical parameters, including the level of stone-forming substances were within the reference values. In urine tests an increase in some lithogenic substances is detected. Urinary stones in patients with bladder outlet obstruction had a mixed composition, more often phosphates and uric acid salts were detected (75 and 54% of cases, respectively). Considering the nature of metabolism and the increase in uric acid excretion with age, as well as the presence of residual urine in case of bladder outlet obstruction, it can be assumed that uric acid is the primary matrix in cystolithiasis. The data obtained indicate a connection between the infectious process in the bladder and the composition of urinary stones. Against this background, there is a more intensive process of cystolithogenesis.
 CONCLUSIONS: The algorithm for the diagnosis of urinary bladder stones secondary to bladder outlet obstruction should include not only the collection of anamnesis and the performance of routine blood and urine tests, but also specific physical and biochemical studies, as well as assess the biomineralogy of urinary stones, which will make it possible to choose an adequate tactics for the pathogenetic treatment of patients and effective metaphylaxis of stone formation.

Результаты применения препарата растительного происхождения с антиоксидантной защитой при мочекаменной болезни

Dietary supplements are successfully used in many fields of medicine, including urology. In particular, urologists often prescribe dietary supplements for patients with urolithiasis. to study an influence of dietary supplements Nefradoz on the metabolism of the main stone-forming substances and inhibitors of stone formation in patients with urolithiasis. Dietary supplements are successfully used in many fields of medicine, including urology. In particular, urologists often prescribe dietary supplements for patients with urolithiasis. to study an influence of dietary supplements Nefradoz on the metabolism of the main stone-forming substances and inhibitors of stone formation in patients with urolithiasis. A total of 60 patients with urinary stone diseases were included in a single-center prospective randomized study. All patients were divided into 2 groups of 30 people, depending on the treatment. In the main group, patients followed standard diet, received general recommendations and dietary supplements Nefradoz for 28-30 days, 1 capsule (150 mg) 2 times a day with meals. In the control group, patients received only general recommendations and followed standard diet therapy for 28-30 days. The blood biochemical profile and 24-hour urine analysis were evaluated, as well as a urinalysis was performed on daily basis. In patients receiving Nefradoz, urinary uric acid excretion increased by 0.9 mmol/day. It must be emphasized that an increase in uric acid excretion did not exceed the upper normal limit. A tendency towards an increase in urine excretion of sodium (by 54 mmol / day), magnesium (by 1 mmol / day) and citrates (by 0.6 mmol / day) was also found. The analysis of urinalysis showed that in the main group, urine specific gravity was lower than in the control group. Higher urine pH in the main group compared to the control group was also shown. The severity of hematuria with the use of Nefradoz was almost two times lower than in patients who did not receive dietary supplement. Considering our data on the ability of dietary supplement Nefradoz to increase the concentration of main inhibitors of stone formation (magnesium and citrates), Nefradoz can be recommended for patients with urinary stone diseases, especially with concomitant hypomagnesuria and hypocitraturia.

The study of the peculiarities of the diuretic action of 2-oxoindoline acylated derivative – N-[(2-oxoindoliniliden-3)-2-oxyacetyl]-valine propyl ester-[(2-oxoindoliniliden-3)-2-oxyacetyl]-valine propyl este

An important issue of modern medicine is the pharmacological correction of regulatory mechanisms of the excretory renal function aimed to normalize the changed water-electrolytic balance in a diseased body. In order to establish the functional balance and correct renal disorders diuretics are used.Aim. To study the effects of N-[(2-oxoindoliniliden-3)-2-oxyacetyl]-valine propyl ester (the conventional name is “Indolinoren”) on the excretory renal function when the repeated doses are administered in spontaneous diuresis and water load, and to determine a possible mechanism of the diuretic action.Materials and methods. The tests were conducted on white non-pedigree rats. The conditionally effective dose of indolinoren (29.5 mg/kg) was intragastrically administered to rats with spontaneous diuresis and water load for 7 days. The values of the excretory renal function were studied.Results. Both under conditions of spontaneous diuresis and under conditions of water load the repeated administration of indolinoren promotes a significant increase of diuresis, which is associated with an increased excretory renal function – natriuresis and, to a lesser extent, kaliuresis. A significant increase in uric acid excretion was observed (by 1.7 and 2 times on day 5 and 7, respectively). It may indicate the uricosuric effect of indolinoren.Conclusions. It has been determined that the possible mechanism of the diuretic action of indolinoren is associated with inhibition of tubular reabsorption, which is indirectly indicated by the increase of natriuresis and kaliuresis on the background of the simultaneous urination increase. The uricosuric properties of indolinoren have been found, it is indicated by an increase of uric acid excretion; these findings require further confirmation.

Fish Oil Supplementation and Urinary Oxalate Excretion in Normal Subjects on a Low-oxalate Diet

To determine if fish oil supplementation reduces endogenous oxalate synthesis in healthy subjects. Fifteen healthy non-stone-forming adults participated in this study. Subjects first abstained from using vitamins, medications, or foods enriched in omega-3 fatty acids for 30 days. Next, they collected two 24-hour urine specimens while consuming a self-selected diet. Subjects consumed an extremely low-oxalate and normal-calcium diet for 5 days and collected 24-hour urine specimens on the last 3 days of this diet. Next, the subjects took 2 fish oil capsules containing 650-mg eicosapentaenoic acid and 450-mg docosahexaenoic acid twice daily for 30 days. They consumed a self-selected diet on days 1-25 and the controlled diet on days 26-30. Twenty-four-hour urine samples were collected on days 28-30. Excretion levels of urinary analytes including oxalate and glycolate were analyzed. Although there was a significant reduction in urinary oxalate, magnesium, and potassium excretions and an increase in uric acid excretion during the controlled dietary phases compared with the self-selected diet, there were no significant differences in their excretion during controlled diet phases with and without fish oil supplementation. These results suggest that fish oil supplementation does not reduce endogenous oxalate synthesis or urinary oxalate excretion in normal adults during periods of extremely low oxalate intake. However, these results do not challenge the previously described reduction in urinary oxalate excretion demonstrated in normal subjects consuming a moderate amount of oxalate in conjunction with fish oil.

Effects on Uric Acid Metabolism of the Drugs except the Antihyperuricemics

A number of drugs commonly used in clinical practice can affect the serum concentration of uric acid. Some raise serum uric acid level by an increase in uric acid production or a decrease in uric acid excretion, while others lower serum uric acid level by an increase in uric acid excretion or decrease in uric acid absorption from intestine. In addition, salicylate shows so-called “biphasic effect”. At small doses it raises serum uric acid level, while at higher doses it lowers serum uric acid concentration. To understand the effects of those pharmacological agents on uric acid metabolism will help to avoid unexpected side effect of hyperuricemia and gout flare. In addition, hypouricemic property of some drugs may obviate the need for polypharmacy and improve the medication compliance.

FRI0403 Arhalofenate, a novel uricosuric agent, is an inhibitor of human URIC acid transporters

BackgroundIt is estimated that the hyperuricemia in 80- 90% of gout patients is due to under excretion of uric acid. Uricouric drugs decrease serum uric acid by causing a reciprocal...

Antihyperuricemic Effect of Ethanol Extract of Snake Fruit (Salacca edulis Reinw.) var. Bongkok on Wistar Male Rat

The aim of the study was to investigate antihyperuricemic effect of snake fruit (Salacca edulis Reinw.) var. Bongkok Wistar male rates. Antihyperuricemic investigation on Wistar male rats showed that administration of ethanol extract at doses of 200 mg/kg bw decreased serum uric acid level significantly compared to control group at hour 6 and 7 (P < 0.05) after inducing with potassium oxonate intraperitoneally simultaneously with uric acid orally. Whereas, administration of ethanol extract at doses of 100 mg/kg bw did not decrease serum uric acid level significantly different compared to control group at hour 6 and 7 (P < 0.05). Determination of uric acid level in urine, administration of ethanol extract at a dose of 200 mg/kg bw, or probenecid as a standard drug, at a dose of 45 mg/kg bw increased excretion of urine uric acid level significantly different compared to control group in day of 7 (P < 0.05) after inducing with potassium oxonate intraperitoneally simultaneously with uric acid orally. However, increase of uric acid excretion by ethanol extract was lower compared to that of probenecid at a dose of 45 mg/kg bw. Mechanism of action of the ethanol extract as an antihyperuricemia has been proposed by inhibition of xanthine oxidase and finally decreased the synthesis of uric acid and increased the excretion of urine uric acid level.

Regulation of renal organic anion transporter expression and function in ACTH‐treated mice

Our previous renal microarray studies indicated differential expression of genes encoding organic anion transporters in a mouse model of ACTH‐dependent Cushing syndrome (Physiological Genomics 40: 158, 2010). In the current study, we used quantitative PCR to show significantly (P&lt;0.01) reduced expression of genes encoding OATP‐1 (slco1a1), OAT2 (slc22a7) and OAT3 (slc22a8) in the kidneys of ACTH‐treated mice (n=6/6). In separate groups of mice, a 14‐day treatment with ACTH (n=5) caused hypertension, polyuria and a four‐fold increase in uric acid excretion, compared to controls (n=6). This is consistent with down‐regulation of OAT3, which contributes to the reabsorption of uric acid. ACTH‐treated mice also had a significantly reduced renal clearance of p‐aminohippurate (cPAH), a prototypical substrate of the OAT system. Since cPAH was not affected by co‐administration of probenecid, it is likely that organic anions normally secreted via this pathway are largely excreted by filtration during chronic glucocorticoid excess. These data indicate that organic anion transport in the kidney is physiologically regulated by corticosteroids. Since several classes of drugs are excreted via this pathway, our data have therapeutic implications in conditions of steroid excess.

Use of Blemaren citrate formula in gout patients with nephrolithiasis

Objective - to evaluate the effect of Blemaren on uric acid (UA) metabolic parameters in gout patients with nephrolithiasis and the possibilities of its use in combined therapy for gout. Patients and methods. The study included 30 patients (26 males and 4 females) aged 50 years (range 36 to 61 years) who had crystal-verified gout in the presence of nephrolithiasis. All the patients took Blemaren in an initial dose of 3 g/day; the dose of the drug was adjusted depending on the urine acidity (the pH value was maintained at 6,2-6,8). Physical and laboratory studies were conducted before and a month after the drug's administration. The treatment performed before the patients ' inclusion into the study remained the same for at least 2 months. Fifteen patients received allopurinol in a dose of 100-200 mg/day. Results. After completion of a course of Blemaren therapy, there was an 8% reduction in the mean serum UA levels, which correlated with an increase in its daily excretion (by an average of 20%). The highest increase in UA excretion was observed in 20 patients with baseline hypoex-cretion ( 700 mg/day). Side effects that could cause the agent to be discontinued were absent. Conclusion. The Blemaren citrate formula used in gout patients with nephrolithiasis causes a significant increase in the renal excretion of UA (p = 0,01), normalizes its metabolic parameters, and shows a high safety, without worsening hepatic and renal functions and electrolyte metabolism.

Renal hypouricemia is an ominous sign in patients with severe acute respiratory syndrome

Background: The purpose of this study is to determine the incidence and significance of hypouricemia in patients with severe acute respiratory syndrome (SARS). Pulmonary lesions in patients with SARS are thought to result from proinflammatory cytokine dysregulation. Acute renal failure has been reported in patients with SARS, but whether cytokines can injure renal tubules is unknown. Methods: Sixty patients diagnosed with SARS in Taiwan in April 2003 were studied. Patients were identified as hypouricemic when their serum uric acid (UA) level was less than 2.5 mg/dL (<149 μmol/L) within 15 days after fever onset. Urine UA and creatinine levels were available for 43 patients; the serum cytokines interleukin-6 (IL-6), IL-8, and tumor necrosis factor-α (TNF-α) were measured in 16 patients. Results: Sixteen patients (26.7%) had hypouricemia (UA, 1.68 ± 0.52 mg/dL [100 ± 31 μmol/L]). No differences in age, sex, symptoms, vital signs, hemogram, or other biochemistry data existed between the hypouricemic and normouricemic groups. Fractional excretion (FE) of UA (FEUA) in 12 hypouricemic patients was 39.6% ± 23.4%, significantly greater than that of 31 normouricemic patients (16.4% ± 11.4%; P < 0.0001). After adjustments for age and sex, high FEUA was significantly associated with the lowest blood oxygenation (P = 0.001; r = −0.624). The number of catastrophic outcomes (endotracheal intubation and/or death) adjusted for older age and sex showed that hypouremic patients had an odds ratio of 10.57 (confidence interval, 2.33 to 47.98; P = 0.002). Kaplan-Meier curves for catastrophic outcome–free results showed significant differences between patients with normouricemia or hypouricemia (P = 0.01). Serum IL-8 levels correlated significantly with FEUA (P < 0.001; r = 0.785) and inversely with serum UA level (P = 0.044; r = −0.509); neither IL-6 nor TNF-α level showed such correlations. Conclusion: One fourth of patients with SARS developed hypouricemia, which might result from a defect in renal UA handling and was associated with a high serum IL-8 level. Renal hypouricemia is an ominous sign in patients with SARS.

Effect of sulphur mustard inhalation exposure on some urinary variables in mice.

The effect of sulphur mustard (2,2'-dichlorodiethyl sulphide) exposure through inhalation at 0.5. 1.0 and 2.0 LC50 (21.2, 42.3 and 84.6 mg m(-3) for 1 h) on some urinary variables was studied in female mice at 6, 24 and 48 h and 7 days post-exposure. The urinary excretion and circulatory blood accumulation of uric acid increased significantly. The level of creatine was also elevated significantly as compared to the control at 2 LC50. It is concluded that sulphur mustard alkylates DNA and triggers catabolism of apurinated purine bases in a very short time. The increase in uric acid excretion in urine can be detected only when the exposure concentration is high.

Energy Metabolism in Genetically Fat and Lean Chickens: Diet- and Cold-Induced Thermogenesis

Energy metabolism was investigated by using indirect calorimetry in growing chickens of similar body weight but genetically selected for high (fat line, FL) or low (lean line, LL) abdominal fat content. Twelve 5- and 7-wk-old male chickens of each line were exposed at two different ambient temperatures, 10 and 25 degrees C. Two birds from the same line were placed in each calorimeter chamber for a 6-d period (2 d fasting and 4 d feeding). Similar food intakes and metabolizabilities of diet corrected for nitrogen balance revealed that FL and LL chickens ingested the same amount of metabolizable energy (ME). Moreover diet-induced thermogenesis did not appear to be defective in FL birds, and the maintenance ME requirement was similar in both lines. However, the partition of retained energy between fat and protein did differ with increased protein deposition and conversely, decreased fat retention in LL chickens, irrespective of age or ambient temperature. FL birds catabolized a greater proportion of dietary amino acids as confirmed by the increase in uric acid excretion. Finally, energy expenditure was significantly and similarly enhanced in both genotypes by cold exposure.

Mechanisms of hypouricemia in the syndrome of inappropriate secretion of antidiuretic hormone.

Hypouricemia seen with hyponatremia related to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) results from an increase in uric acid renal clearance. We studied the mechanism of the increase of uric acid excretion in 6 SIADH patients through pyrazinamide (PZA), which decreases tubular secretion of uric acid, and sulfinpyrazone (SPZ) which decreases post-secretory reabsorption of uric acid. 3 g of PZA decreased the absolute uric acid excretion from 428 +/- 244 to 105 +/- 47 micrograms/min (mean +/- SD, p less than 0.01), and 300 mg of SPZ increased the uric acid to creatinine clearance ratio from 0.31 +/- 0.05 to 0.52 +/- 0.05 mg/dl glomerular filtration rate (mean +/- SEM, p less than 0.001), which represent an increment about half of that observed in the control group. The increase of uric acid clearance in SIADH seems to result from a decrease in the post-secretory reabsorption of uric acid. After SPZ, we saw a decrease of natriuresis from 5.6 +/- 1.4 to 1.8 +/- 0.3 mmol/h (p less than 0.001), without any change of urinary flow or urinary potassium excretion.

Cecae of desert quail: Importance in modifying the urine

1. 1.The importance of the digestive ceca in the modification of ureteral urine was evaluated in conscious, unrestrained desert quail. 2. 2.Cecaectomized (Cx) birds took in slightly more food and water and excreted more solids and water than did sham operated controls. 3. 3.The percent utilization of food for the Cx birds was 76 and 79% for the sham operated controls. 4. 4.Urate output was 47 ml/kg day for Cx and 41 ml/kg day for the sham operated controls. 5. 5.Water content of the excrement was 90% for the Cx and 85% for the sham operated controls. 6. 6.There was a slight but insignificant increase in uric acid excretion in the droppings of cecaectomized birds.

Effects of dietary pyridoxine on larval growth, free amino acid pattern in haemolymph and uric acid excretion in the silkworm, Bombyx mori

The effects of the lack of, or varying levels of, pyridoxine in the diet on larval growth, free amino acid composition of the haemolymph and uric acid excretion in the silkworm, Bombyx mori, were determined. Under pyridoxine-deficient conditions, growth of larvae and silkglands was retarded, being accompanied by an inhibition of the increase of haemolymph protein content and an increase in uric acid excretion. The pyridoxine requirement was larger for the growth of silkglands than that for the whole body. The free amino acid composition of the haemolymph was greatly altered by pyridoxine deficiency and the effect became more pronounced with the prolongation of the duration of feeding on a deficient diet. The contents of glycerophosphoethanolamine, phosphoethanolamine, Gly, Glu-NH 2, cystathionine and ornithine in haemolymph were markedly increased by pyridoxine deficiency, whereas the contents of Thr, Ser, Ala, lanthionine, Met, Leu, Tyr, Phe, Lys and His fell. The levels of amino acids approached the control levels of the respective amino acids with the increase of dietary pyridoxine concentration.

Digestion of fat and protein and its relation to the activity of faecal enzymes in mucoviscidosis infants under substitution therapy with pancreatic enzymes (author's transl)

The article reports on a study to determine the influence of different dosage schedules of a pancreas enzyme preparation on the digestion of fat and protein and on the lipolytic, tryptic and chymotryptic activity of the faeces in children suffering from mucoviscidose. After administration of the pancreatin preparation at the low dose level, the quantity of faeces, the excretion of fatty acids and of nitrogen are reduced and the absorption coefficient is improved. The faecal tryptic and chymotryptic activity increases, whereas the lipase activity in the faeces merely shows a tendency to rise. Increasing the pancreatin dose up to a still tolerable value by doubling the dosage does not result in further reduction of the excretion of fat and nitrogen although it enhances the proteolytic activity of the faeces while the lipase activity remains unaffected. Determination of the lipolytic, tryptic or chymotryptic activity is, therefore, unsuitable for assessing the fat and protein digestion and for estimating the required dose of pancreatic enzyme. No increase in uric acid excretion was seen in the urine collected for 24 hours after administration of both enzyme doses.

The physiological and biochemical responses of broilers exposed to short-term thermal stress

1. 1. Exposure of cockerels to heat stress (42°C) for 15 min resulted in a reduction of both the total free and essential free amino acids in plasma with simultaneous elevation in the levels of the total free and essential free amino acids in liver as compared to the pre-stress level. 2. 2. The reduction in the plasma free amino acid pools was accompanied by a decrease in total proteins and alkaline phosphatase concentrations, with a simultaneous elevation in albumin, glucose, uric acid, plasma free fatty acids, lactate dehydrogenase and creatine kindase. 3. 3. During the recovery period both the total plasma and hepatic free amino acids returned to prestress levels but the levels of the essential plasma free amino acids in heat-stressed birds remained low while the hepatic essential free amino acids remained high. 4. 4. At the end of a 30 min recovery period at 21°C, the glucose content substantially decreased with free fatty acids and uric acid still remaining at high levels. 5. 5. There was a significant reduction in nitrogen retention in heat-stressed birds determined during the 24 hr recovery period mainly due to an increase in the excretion of nitrogen in uric acid form. 6. 6. In birds exposed to cold (4°C), the only significant changes were an increase in the hepatic essential free amino acids and an increase in uric acid excretion. 7. 7. The results indicate that short-term heat stress affects protein metabolism in growing chickens.

Effect of sulphinpyrazone (Anturan) on uric acid excretion and plasma uric acid concentration in healthy volunteers.

Investigations in six healthy volunteers given single oral doses of sulphinpyrazone (Anturan) showed that the drug had a potent uricosuric effect, even if the concentration of uric acid in the plasma was normal. In the dose range tested of 50 to 800 mg the increase in uric acid excretion was dose-related. It reached a maximum within 2 h and was still detectable 6--8 h after the drug was taken. There was a corresponding dose-related reduction in the plasma concentration of uric acid, which reached its lowest level after 8--10 h. The administration of 300 mg twice daily for four days to a further five healthy volunteers reduced plasma uric acid from 5.06 to 1.8 mg%. The findings indicate that, even if plasma uric acid levels are unknown, it would be advisable to avoid the risk of formation of urinary calculi by administering sulphinpyrazone in gradually increasing doses, ensuring adequate fluid intake and alkalinizing the urine during the first few days of treatment.

The utilization of protein and excretion of uric acid in germ-free and conventional chicks.

1. The influence of the gut microflora on protein utilization has been investigated with a series of good- and poor-quality protein diets in germ-free (GF) and conventional (CV) chicks by the measurement of net protein utilization (NPU) and uric acid excretion.2. The diets used were: 280 g protein per kg diet containing unheated or heat-damaged albumen (100 g/kg), casein (80 g/kg) and gelatin (100 g/kg); sesame protein (220 g/kg); sesame protein (220 g/kg) supplemented with lysine (5 g/kg); freeze-dried cod muscle (160 g/kg); heat-damaged cod muscle (160 g/kg); mildly-steamed egg albumen (100g/kg); heat-damaged egg albumen (100 g/kg).3. No significant differences in NPU values for the proteins measured in GF and CV chicks were found, with the exception of unsupplemented sesame protein, for which the NPU value was slightly higher in GF chicks.4. The replacement of unheated egg albumen by heat-damaged egg albumen in the 280 g protein/kg diet resulted in a decrease in uric acid excretion. With the cod-muscle diets, heat-damaging the protein caused an increase in uric acid excretion. Supplementing the sesame protein with lysine resulted in a decrease in uric acid excretion.5. Excretion of uric acid tended to be higher in CV chicks than in GF chicks with all proteins except sesame protein, with which uric acid excretion was a little higher in GF chicks.6. Endogenous nitrogen excretion was higher in GF than in CV chicks.7. It is concluded that the gut microflora has little influence on the utilization of dietary protein by chicks, although it may modify the route of excretion of the N which survives digestion and reaches the lower gut.