Nitrogen Excretion in Developing Chick Embryos

Development ◽  
1957 ◽  
Vol 5 (3) ◽  
pp. 215-224
Author(s):  
James R. Fisher ◽  
Robert E. Eakin
Keyword(s):  
Uric Acid ◽  
Experimental Evidence ◽  
Nitrogen Metabolism ◽  
Metabolic Changes ◽  
Nitrogen Excretion ◽  
Chick Embryos ◽  
The Many

Of the many examples of metabolic changes occurring during development, the most widely cited is that in developing chicks wherein the end product of nitrogen metabolism has been assumed to shift from ammonia to urea and finally to uric acid (Needham, 1931). This system appeared to be ideal for a proposed study of the mechanisms bringing about such changes in metabolism, providing the occurrence of these changes could be further substantiated. The experimental evidence upon which this pattern had been postulated consisted entirely of measurements of the total amounts of ammonia, urea, and uric acid in the allantois and the ratio of their total weights to the weight of the embryo. Nothing was reported concerning the changes in concentration of these substances nor their presence outside the allantois. Lack of this information makes it impossible to conclude that net synthesis occurs, particularly in the cases of ammonia and urea where the total amounts present are quite small.

Nitrogenous Excretion of Amphipods and Isopods

1950 ◽  
Vol 27 (2) ◽  
pp. 210-225
Author(s):  
ELISABETH I. B. DRESEL ◽  
VIVIEN MOYLE
Keyword(s):  
Uric Acid ◽  
Nitrogen Metabolism ◽  
Fresh Water ◽  
Gammarus Pulex ◽  
Nitrogen Excretion ◽  
Physiological Adaptation ◽  
Asellus Aquaticus ◽  
Terrestrial Species ◽  
Water Species ◽  
Eleven Species

1. The nitrogen excretion of eleven species of amphipods and isopods, including marine, fresh-water and terrestrial forms, has been studied. 2. All species are essentially ammonotelic, since more than 50% of the total soluble N.P.N. of the excreta was present in the form of ammonia throughout. 3. The level of nitrogen excretion is appreciably lower in the terrestrial species than in any of the others, indicating that, in this group, adaptation to terrestrial conditions has been attended by a general suppression of nitrogen metabolism rather than by a transformation of ammonia to other, less toxic products. 4. Some 5-10% of the total soluble N.P.N. was present as urea in the case of the fresh-water amphipod, Gammarus pulex, and as uric acid in the terrestrial isopods as well as the fresh-water isopod, Asellus aquaticus. It is suggested that these minor excretory components might originate from purines as a result of the loss of one or more of the uricolytic enzymes. 5. In association with the excretion of uric acid some retention of this insoluble compound usually occurs, and it was found that among the terrestrial species the amount so stored parallels the degree of morphological and physiological adaptation to terrestrial conditions. The greatest accumulation of uric acid was, however, observed in the fresh-water species, A. aquaticus, and although such a storage cannot necessarily be taken as evidence for a partially uricogenic metabolism, this possibility must be borne in mind.

scholarly journals Nitrogenous metabolism in Thoroughbred and Arabian foals from birth to five months of age

2006 ◽  
Vol 58 (4) ◽  
pp. 525-529 ◽  
Author(s):  
G. Piccione ◽  
A. Costa ◽  
F. Fazio ◽  
F. Grasso ◽  
G. Caola
Keyword(s):  
Uric Acid ◽  
Serum Concentration ◽  
Nitrogen Metabolism ◽  
Rectal Temperature ◽  
Total Protein ◽  
Critical Period ◽  
Critical Period Of Development ◽  
Over Time ◽  
Time Point ◽  
Nitrogenous Metabolism

The maturation of nitrogen metabolism was studied in six Thoroughbred and six Arabian foals. Rectal temperature, heart and respiratory rates and serum concentration of several hematochemical parameters (total protein, urea, uric acid, creatinine, and albumine) were monitored from birth to 5 months of age. In both breeds, all the parameters except albumine showed significant differences over time (P<0.05). The two breeds did not differ from each other at any time point. Statistically significant decreases in urea and creatinine concentrations were related to the growth needs of foals during this critical period of development.

Nitrogen Excretion in Ascidiacea II. Storage Excretion and the Uricolytic Enzyme System

1965 ◽  
Vol 42 (2) ◽  
pp. 299-305
Author(s):  
IVAN GOODBODY
Keyword(s):  
Uric Acid ◽  
Calcium Carbonate ◽  
Protein Metabolism ◽  
Enzyme System ◽  
Purine Metabolism ◽  
Nitrogen Excretion ◽  
Purine Base ◽  
Purine Bases ◽  
Ascidiella Aspersa

1. The evidence for the occurrence of storage excretion in ascidians is reviewed. Most species probably store uric acid or purine bases in some form. 2. The renal concretions of Ascidia nigra and Phallusia mammillata contain 50-60% uric acid, the remainder of the concretion is unidentified but is non-nitrogenous and is not calcium carbonate. In Ascidiella aspersa the concretion is predominantly composed of calcium carbonate and there is no significant quantity of uric acid or purine base. 3. Uric acid is also identified in Molgula manhattensis, Polycarpa obtecta, Pyura vittata and Herdmania momus. 4. Storage excretion probably results from a deficiency in the uricolytic enzyme system. It is concluded that while protein metabolism is ammonotelic, purine metabolism is uricotelic or xanthotelic.

Nitrogen excretion in germ-free and conventional chickens: effects of an alkali load

1978 ◽  
Vol 39 (1) ◽  
pp. 99-104 ◽  
Author(s):  
J. Okumura ◽  
D. Hewitt ◽  
Marie E. Coates
Keyword(s):  
Amino Acids ◽  
Uric Acid ◽  
Ammonia Excretion ◽  
Nitrogen Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Total N ◽  
Germ Free ◽  
Base Balance ◽  
Micro Organisms

1. Groups of three colostomized germ-free (GF) and conventional (CV) chickens aged 4 months were maintained for successive periods of 8 d on a diet containing 200 g casein/kg without and with sodium bicarbonate at the rate of 20 mmol/d and a nitrogen-free diet without and with NaHCO3at 9 mmol/d. Urine and faeces were collected during the last 3 d of each period.2. Total N, uric acid- and ammonia-N were determined in urine and total N in faeces. Amino acids were measured in hydrolysates of faeces collected during the periods when no NaHCO3was included in the diets.3. The CV birds excreted more N on the casein diets but less on the N-free diets than did their GF counterparts, the differences being mainly shown in the urine.4. On both diets hydrolysates of the faeces of CV birds contained smaller amounts of amino acids. On the N-free diet the proportions (g/160 g N) of serine, proline and threonine were reduced, suggesting some conservation of endogenous N by micro-organisms, and the proportions of histidine, alanine, lysine and methionine increased, possibly through microbial synthesis; on the casein diet, proportions of most amino acids were less, probably because bacterial deamination had occurred.5. Urinary excretion of total N, uric acid and ammonia was much greater on the casein than on the N-free diets. Inclusion of NaHCO3caused a sharp fall in urinary ammonia on both diets and in both environments.6. It was concluded that the level of dietary protein and the regulation of acid-base balance have more effect than microbial activity on the urinary ammonia excretion.

Nitrogen metabolism of two portunid crabs, carcinus maenas and necora puber, during prolonged air exposure and subsequent recovery: a comparative study

1998 ◽  
Vol 201 (17) ◽  
pp. 2515-2528 ◽  
Author(s):  
F Durand ◽  
M Regnault
Keyword(s):  
Nitrogen Metabolism ◽  
Recovery Period ◽  
Carcinus Maenas ◽  
Ammonia Excretion ◽  
Acid Synthesis ◽  
Nitrogen Excretion ◽  
Ammonia Content ◽  
Amino Acid Synthesis ◽  
Air Exposure ◽  
Ammonia Release

Carcinus maenas and Necora puber were exposed to air for 72 h and 18 h, respectively, at 18 degreesC. Nitrogen excretion, blood and muscle ammonia content and blood urate and lactate content were recorded throughout the experimental emersion and following reimmersion (recovery period). During emersion, the rate of ammonia excretion was strongly reduced in both species, while urea and amine excretion were not enhanced. Blood and muscle ammonia content increased steadily, reaching 1.3 and 10.4 mmol l-1, respectively, after an 18 h emersion in N. puber. In contrast, in C. maenas, blood ammonia levels increased slightly during the first 12 h and then remained at this level (approximately 0.12 mmol l-1) until the end of emersion. Muscle ammonia content showed a non-significant increase at 12 h, after which values returned to control values (3.3 mmol l-1) for the next 60 h. Blood urate and lactate content increased in emersed N. puber, indicating strong internal hypoxia, but urate content did not increase in C. maenas until the third day of emersion. Upon reimmersion, both species released large amounts of ammonia within a few minutes. Two different patterns of ammonia release then were observed: ammonia excretion was enhanced for a further 3 h in N. puber, whereas raised ammonia excretion rates were observed for a further 24 h in C. maenas. These patterns, the recovery of blood and muscle ammonia levels and the calculated nitrogen balance between emersed and control crabs indicated that specific processes were used to manage the nitrogen overload induced by air exposure. Whereas N. puber shows little or no ability to limit ammonia accumulation in its body, C. maenas exhibits strong regulation of its nitrogen metabolism. The probability that amino acid synthesis is involved in this regulation and whether these species use metabolic depression as a survival strategy are discussed.

Evaluation of Metabolic Changes in HCV Diabetic Patients Treated With Direct Acting Antiviral Agents

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Engy Yousry Elsayed ◽  
Hany Haroun Saad ◽  
Gina Gamal Naguib ◽  
Hazem Ibrahim Abouelela
Keyword(s):  
Uric Acid ◽  
Hepatitis C Virus ◽  
Liver Disease ◽  
Hepatitis C ◽  
Chronic Liver Disease ◽  
Serum Uric Acid ◽  
Metabolic Changes ◽  
Chronic Liver ◽  
Hcv Infection ◽  
Diabetic Patients

Abstract Background Viral hepatitis is a major public health problem in need of urgent response. The prevalence of hepatitis C virus (HCV) infection in Egypt is the highest in the world. Seroprevalence was modeled to 10.6% and viraemic prevalence to 7.3% in 2014. The association between hepatitis C virus (HCV) infection and diabetes has been widely postulated. Prospective studies have demonstrated a higher risk of developing type 2 diabetes mellitus (T2DM) and insulin resistance in the HCV population. Objective to evaluate metabolic changes in HCV-positive diabetic patients following combination therapy of hepatitis C, clarifying the role of DAAs in these changes. Patients and Methods This study was conducted in Ain Shams University Hospital outpatient clinics who attended from March to December 2018. our study included 70 patients, and were subdivided into the following two groups: Group I: Easy to treat group. Contains 35 diabetic patients with HCV related chronic liver disease treated with sofosbuvir, daclatasvir. Group II: Difficult to treat group. Contains 35 diabetic patients with HCV related chronic liver disease treated with sofosbuvir and daclatasvir and ribavirin. Results Treatment was considered successful when patients became non-viraemic as identified by negative HCV RNA serum PCR at 12 weeks from the end of the treatment regimens (SVR). It was found that diabetic patients treated with DAAs achieved reduction of HbA1C by mean of (0.724±0.3%). The mean increase of serum uric acid level was (0.607±0.4 mg/dL). There were increases in Cholesterol (by mean of 16.85±3.4), HDL (by mean of 5.34±2.1) and LDL (by mean of 13.91±4.2) as well as a decrease in TG (by mean of 13.56±5.1). Conclusion Our study concludes that HCV eradication in diabetic patients leads to various metabolic changes in the form of: Reduction of serum HbA1c level. Elevation of serum uric acid. Elevation of serum cholesterol, HDL, LDL as well as a decrease in TG. Further and larger studies are needed to evaluate the full magnitude of RBV effects on the patients’ metabolism.

The effect of diethylstilbestrol on nitrogen excretion in sheep

1970 ◽  
Vol 48 (8) ◽  
pp. 573-574 ◽  
Author(s):  
T. L. Huber
Keyword(s):  
Nitrogen Metabolism ◽  
Direct Effect ◽  
Tubular Reabsorption ◽  
Arginase Activity ◽  
Nitrogen Excretion ◽  
Plasma Urea ◽  
Urea Excretion ◽  
Nitrogen Conservation ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

Administration of 2 mg of diethylstilbestrol (DES) daily to lambs reduced total urinary nitrogen excretion, urea excretion, plasma urea concentrations, and liver arginase activity. The percent of filtered urea reabsorbed was greater in untreated lambs, thus suggesting that the increased nitrogen conservation observed following DES administration to ruminants is not the result of a direct effect of DES on tubular reabsorption of urea but on nitrogen metabolism.

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