| dc.description.abstract | Among the many nutritional diseases, atherosclerosis has attracted considerable attention of dieticians, pathologists, cardiologists, clinicians and biochemists. This disease, though prevalent in increasing numbers, has not been produced in common laboratory animals. The consumption of a diet rich in fat is one of the many postulated causative factors resulting in the elevation of blood cholesterol. The dietary factor in fat, responsible for induction of hypercholesterolemia, has been controversial. Fats differing in iodine values, viz., groundnut oil, coconut oil, mustard oil, sesame oil, safflower oil, hydrogenated groundnut oil, butter-fat and lard, are commonly used in the diets in this country. Hence, the above fats were tested for their ability to induce hypercholesterolemia in rats. Previously, in this laboratory hypercholesterolemia has been successfully induced in rats by prolonged feeding of a high fat (25%) and cholesterol (1%) diet.
One of the biochemical manifestations of hypercholesterolemia has been the increase in glycoprotein concentrations of blood and liver. In addition, the equilibrium of blood coagulation factors (of which many of them are glycoproteins) were disturbed. Furthermore, in certain pathological states, changes are observed either in the carbohydrate-containing proteins or in their constituents. A glycoprotein, which inhibits tryptic activity and prolongs the coagulation time of plasma, has been isolated from the plasma of sheep, goat, cow, buffalo and monkey. Their physicochemical, biological and immunochemical characterisations have been made and presented in the thesis.
The thesis has been divided into seven chapters.
In Chapter I, a brief introduction regarding the relationship between atherosclerosis and hypercholesterolemia; experimental hypercholesterolemia and the role of dietary fats in hypercholesterolemia has been reviewed. The relation of the disease to plasma glycoprotein and their clinical significance has been discussed. A brief review of the isolation of some of the important glycoproteins, their physical, chemical and structural aspects has been presented. The biosynthesis of -glycoprotein has been briefly discussed.
Chapter II deals with the materials used and methods followed during the course of the present investigations.
The role of dietary fats in the induction of hypercholesterolemia in rats is presented in Chapter III. The biochemical changes in tissues like blood, liver, aorta, and heart in experimental condition have been investigated.
Chapter IV brings out the importance of plasma glycoproteins in the pathological state. The analysis of sera obtained from patients suffering from hypertension, myocardial infarction and liver disorders for carbohydrate constituents indicates the diagnostic value of plasma glycoprotein constituents.
Isolation and physical characterisation of a biologically active glycoprotein from the plasma of sheep, goat, cow, buffalo and monkey have been presented in Chapter V.
Chapter VI deals with the chemical and biological properties of the glycoproteins isolated from plasma of sheep, goat, cow, buffalo and monkey.
Results of immunochemical analyses like agar-gel diffusion, precipitin tests and immunoelectrophoresis of the sheep plasma glycoprotein are presented in Chapter VII. Cross-reaction experiments of heterologous antigens i.e., glycoproteins of goat, cow, buffalo and monkey with the rabbit antisera to sheep glycoprotein have also been presented in this chapter. | |
