Nitrogen Absorption Curves in Health and Disease

Tindal, Margaret T (1933) Nitrogen Absorption Curves in Health and Disease. PhD thesis, University of Glasgow.

Abstract

From the work of physiologists it is established that, after ingestion, protein substances are broken down into primary and secondary proteoses, later into peptone, and ultimately into amino-acids in which form they are absorbed and thus enter the portal circulation. The constituents of which the tissues are capable of making use are distributed by the blood stream to various parts of the body, while those which are not utilised are carried to the kidney where they are removed from the circulation and excreted in the urine. The major portion of this nitrogen found in the urine is composed of urea, ammonium salts and creatinln. Thus far, the processes at work have been extensively investigated and the results obtained have been well substantiated. Much less work has, however, been carried out on the Intermediate metabolism of nitrogen. It would appear that a hiatus exists in our knowledge regarding the part played by the liver in these processes. It is said that deaminisation of the amino-acids occurs in the liver resulting in the formation of urea, but the actual mechanism of the next step is uncertain. After the liver manufactures the urea does it immediately enter the circulation with a view to excretion by the urine as expeditiously as possible? Or, is it possible that the urea may be stored by the liver and only allowed to escape gradually into the blood stream? Lastly, the hypothesis has been brought forward that the urea may be actually resynthetised into protein.The present investigation was undertaken with a view to following the changes in blood non-protein nitrogen which occurred in health and in disease after the ingestion of urea.It was also decided to study the effect of various foodstuffs on the non-protein nitrogen of the blood.The work has accordingly been divided into the following sections: 1. A summary of our present knowledge of the non-protein nitrogen of the blood considered from a historical standpoint along with some remarks on the absorption of urea. 2. The influence of (a) a prolonged abstention from food and (b) various foodstuffs, alone and in combination, on the non-protein nitrogen of the blood. 3. A study of the effect of the ingestion of urea on the non-protein nitrogen of the blood in healthy or convalescent children. 4. The influence of the ingestion of urea on the blood non-protein nitrogen in cases where disease of the liver is known or suspected to exist. 5. The effect of the ingestion of urea on the non-protein nitrogen of the blood in diseases of the muscles. 6. The effect of the ingestion of urea on the non-protein nitrogen of the blood in children who were the subjects of rheumatic infection. 7. The effect of the ingestion of urea on the non-protein nitrogen of the blood in cases of renal disease. 8. The influence of the ingestion of urea on the non-protein nitrogen of the blood in cases of coeliac disease. 9. Summary and conclusions.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Medicine, Physiology
• Date of Award: 1933
• Depositing User: Enlighten Team
• Unique ID: glathesis:1933-79998
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 03 Mar 2020 10:12
• Last Modified: 03 Mar 2020 10:12
• URI: https://theses.gla.ac.uk/id/eprint/79998