Sequential changes in lipoprotein lipase activity and lipaemia induced by the Yoshida AH-130 ascites hepatoma in rats.
The implantation of the Yoshida AH-130 ascites hepatoma to rats resulted in an exponential growth of the tumour cells followed by a late stationary phase. The tumour burden was accompanied by a dramatic decrease in body weight. Tumour growth was associated with a marked hypertriglyceridaemia during the period of exponential growth, while in the stationary phase the plasma triacylglycerol concentration was similar to that observed in the non-tumour-bearing animals. Similar increases were observed, following tumour inoculation, in the plasma concentrations of non-esterified fatty acids and glycerol, suggesting an intense lipolytic activity. These changes in lipaemia were associated with a marked decrease in LPL activity in white adipose tissue; in contrast, LPL activity was increased in the tumour-bearing animals in brown adipose tissue at day 6 following inoculation and in the heart during most of the period studied. Although the presence of the tumour did not induce any changes in blood lactate concentrations, it caused a decrease in circulating glucose; conversely, the tumour induced an important increase in the concentration of circulating ketone bodies, suggesting a metabolic adaptation of the tumour-bearing rats to glucose sparing and alternative fuel utilization. It may be suggested that the hyperlipidaemia present in the Yoshida AH-130 bearing rats is partly due to a decreased LPL activity in white adipose tissue which does not seem to be influenced by changes in insulin circulating concentrations.
López-Soriano
J
J
Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Spain.
Argilés
J M
JM
López-Soriano
F J
FJ
D000818:Animals; D001835:Body Weight; D005260:Female; D015228:Hypertriglyceridemia / Q000209:etiology*; D007657:Ketone Bodies / Q000097:blood; D008071:Lipoprotein Lipase / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D007657:Ketone Bodies; D008071:Lipoprotein Lipase