Yonsei Med J.  1968 Dec;9(2):139-148. 10.3349/ymj.1968.9.2.139.

The Effects of Partial Hepatectomy and Induced Hypothyroidism on the Tissue Lipid Distribution in Rats

• Kim SC
• Choi IJ
• Lee YB
• Kim DS

• KMID: 877109
• DOI: http://doi.org/10.3349/ymj.1968.9.2.139

Abstract

The nature of the resistance in the rat to the development of experimental atherosclerosis is unknown, and its elucidation on mechanisms is vital to further knowledge of the pathogenesis of the disease. The liver is the main organ where cholesterol synthesis predominantly occurs and is also the main source for the plasma cholesterol. One of the factors which regulates the cholesterol metabolism is the thyroid hormone, that is a well known fact. Therefore, with combination of partial hepatectomy and administration of thiouracil, alteration of tissue lipid distribution was studied. 1. Exogenous high cholesterol feeding did not elevate the total serum cholesterol and partial hepatectomized rats, but did cause significant alterations in the tissue lipid distribution. particularly in the adrenal gland, small intestine, liver and kidney. The thyroid gland became hyperplastic. 2. The combined administration of Tapazole and cholesterol caused only a slight elevation of the serum cholesterol level as compared with that of controls, but very significant alterations in the tissue lipid distribution in the adrenal gland and liver. 3. The combined administration of Thyroxine and cholesterol caused only a tendency to minimal decrement of serum cholesterol level as compard with that of controls, but produced a significant inhibition of tissue lipid accumulation in the liver and kidney. 4. Partial hepatectomy caused neither the changes in serum cholesterol level, nor effect of the tissue lipid distribution. 5. Lipid accumulation in the coronary artery and aorta could not be demonstrated, although there was some alteration in the serum cholesterol level and in the tissue lipid distributon. It appears that, in the rats, there was no particular alteration of the intestinal absorption of cholesterol regardless of the thyroid status, and in the pathways of cholesterol metabolism after absorption, partial hepatectomy did not induce particular effect, but changes in the thyroid function did show measurable effects. However, the fact that there were no significant elevations in the serum cholesterol and tissue lipid in the liver suggests that homeostatic mechanisms may have a greater role in the high resistance to the development of atherosclerosis than does an actively functioning thyroid gland.

MeSH Terms

Animals
Cholesterol/*metabolism
*Hepatectomy
Hypothyroidism/*metabolism
Lipids/*metabolism
Male
Rats