Hepatic denervation impairs the assembly and secretion of VLDL-TAG

• Published in: Cell biochemistry and function 2008-07, Vol.26 (5), p.557-565
• Main Authors: Tavares, Fábio Luís, Seelaender, Marília Cerqueira Leite
• Format: Article
• Language: English
• Subjects: Animals; Apolipoproteins B - metabolism; Cholesterol - blood; Denervation; lipoprotein; Lipoproteins, VLDL - antagonists & inhibitors; Lipoproteins, VLDL - biosynthesis; Lipoproteins, VLDL - blood; Lipoproteins, VLDL - secretion; liver; Liver - innervation; Liver - metabolism; Liver - secretion; Male; noradrenaline; Rats; Rats, Wistar; Triglycerides - antagonists & inhibitors; Triglycerides - biosynthesis; Triglycerides - blood; Triglycerides - secretion; VLDL
• ISSN: 0263-6484; 1099-0844
• DOI: 10.1002/cbf.1476

VLDL secretion is a regulated process that depends on the availability of lipids, apoB and MTP. Our aim was to investigate the effect of liver denervation upon the secretion of VLDL and the expression of proteins involved in this process. Denervation was achieved by applying a 85% phenol solution onto the portal tract, while control animals were treated with 9% NaCl. VLDL secretion was evaluated by the Tyloxapol method. The hepatic concentration of TAG and cholesterol, and the plasma concentration of TAG, cholesterol, VLDL‐TAG, VLDL‐cholesterol and HDL‐cholesterol were measured, as well as mRNA expression of proteins involved in the process of VLDL assembly. Hepatic acinar distribution of MTP and apoB was evaluated by immunohistochemistry. Denervation increased plasma concentration of cholesterol (125.3 ± 10.1 vs. 67.1 ± 4.9 mg dL−1) and VLDL‐cholesterol (61.6 ± 5.6 vs. 29.4 ± 3.3 mg dL−1), but HDL‐cholesterol was unchanged (45.5 ± 6.1 vs. 36.9 ± 3.9 mg dL−1). Secretion of VLDL‐TAG (47.5 ± 23.8 vs. 148.5 ± 27.4 mg dL h−1) and mRNA expression of CPT I and apoB were reduced (p