The authors examined the effects of splenectomy on serum lipids in patients with hematologic disease, in rabbits, and also in cholesterol-fed rabbits with experimental atherosclerosis.
Serum cholesterol was determined in patients with hypersplenism before and after splenectomy. Meanwhile serum lipids were determined in two groups of rabbits: splenectomy group (Spx group, n = 19), and sham operation group (Sham group, n = 14) before and after the operation. Then the rabbits were divided into four subgroups: cholesterol-fed groups-Spx-C (n = 12) and Sham- C (n=9), and normal-chow-fed groups-Spx-N (n=7) and Sham-N (n=5). The Spx-C and the Sham-C rabbits were fed 1% cholesterol diet and the Spx-N and the Sham-N rabbits were fed normal chow for twelve weeks. In patients preop erative serum cholesterol levels were low, and significant increase in serum cho lesterol was observed following splenectomy. In rabbits, the Spx-C group showed significantly higher levels of serum cholesterol, triglycerides, and phos pholipids in contrast to lower levels of high density lipoprotein cholesterol, as compared with the Sham-C group. The percentage of aortic plaque area in the Spx-C group tended to be higher than that in the Sham-C group. On the other hand, the Spx-N and the Sham-N group showed no difference in serum lipids during twelve weeks. The worsening of atherosclerosis in the Spx-C group was considered to be mainly due to an enhanced hyperlipidemia.
Their results suggest a possible role of the spleen in lipid metabolism, in particular the existence of a splenic factor that can cause hypocholesterolemia in hyperplenism and can suppress hyperlipidemia.
Get full access to this article
View all access options for this article.
References
1.
Sugihara T., Yawata Y.: Observations on plasma and red cell lipids in hereditary spherocytosis. Clin Chim Acta137:227-232, 1984.
2.
Gilbert HS, Ginsberg H.: Hypocholesterolemia as a manifestation of disease activity in chronic myelocytic leukemia. Cancer51:1428-1433, 1983 .
3.
Gilbert HS, Ginsberg H., Fagerstrom R., et al: Characterization of hypocholesterolemia in myeloproliferative disease. Am J Med71:595-602, 1981.
4.
Aviram M., Brook Djg, Tatarsky I., et al: Increased low-density lipoprotein levels after splenectomy: A role for the spleen in cholesterol metabolism in myeloproleferative disorders . Am J Med Sci291:25-28, 1986.
5.
Sardesai VM, Manning JA: The determination of triglyceride in plasma and tissues. Clin Chem14:156-161, 1968.
6.
Sakurabayashi I., Kawai T.: Clinical aspects of quantitative serum lipoprotein fractionation by the heparin-Ca precipitation method. Jpn J Atheroscler4:151-155, 1976.
7.
King JH: Studies in the pathology of the spleen. Arch Intern Med14:145-167, 1914.
8.
Constantinides P.: Experimental atherosclerosis in the rabbit. In: Comparative Atherosclerosis, ed. by Roberts JC, Straus R.New York: Harper & Row, 1965, pp. 276-290.
9.
Clair RW: Atherosclerosis regression in animal models—current concepts of cellular and biochemical mechanism. Prog Cardiovasc Dis26:109-132, 1983.
10.
Goldstein JL , Brown MS: The low-density lipoprotein pathway and its relation to atherosclerosis. Ann Rev Biochem46:897-903, 1977.
11.
Kovanen PT, Brown MS, Basu SK, et al: Saturation and suppression of hepatic lipoprotein receptors: A mechanism for the hypercholesterolemia of cholesterol-fed rabbits. Proc Natl Acad Sci USA78:1396-1400, 1981 .
