The Study Of Hyperlipidemic ’s Effect On Brain Lipid Metabolism In Rats

Objects:In order to understand the relationships between lipid metabolism in brain tissue and peripheral organization, the different serum lipid content’s effect on hepatic and brain lipid metabolism in rats was discussed, which could provide a new inspiration on some brain diseases’s prevention and cure.Methods:By total cholesterol(TC)and body weight,32adult male SD rats were randomized into five groups, a normal control group C, fed with basic feed; a high-fat model group M1, fed with high-fat feed in one week; a high-fat model group M2, fed with high-fat feed in two weeks; a high-fat model group M3, fed with high-fat feed in three weeks. The high-fat feed was composed of94.5%basic feed,4%cholesterol,1%Bile acid, and0.5%propylthiouracil. Lipid, apolipoprotein E(ApoE), low density lipoprotein receptor(LDLR),24-hydroxy cholesterol(24-HyC) in serum, liver and brain were measured, and sections of the hippocampal CA1region were prepared.Result:1. At the end of one week fed with high-fat feed, the content of serum TC, TG, LDL-C, HDL-C in model group rats were4.52,2.24,5.11,0.54times than that of group C respectively, which showed that the Hyperlipidimia model was estabished successly, the content of serum TC, TG, LDL-C, LDLR,24HyC in model group rats increased(P<0.05) with the experiment going, but the ApoE, LDLR content didn’t change(P>0.05); the content of hapatic TC, TG, LDL-C,ApoE increased(P<0.05) with the experiment going, the content of HDL-C decreased(P<0.05), the content of LDLR raised firstly and then decreased(P<0.05), the content of24hyC didn’t change(P>0.05); The brain content of TG, LDLR,24HyC increased (P<0.05) with the experiment going, the content of HDLC decreased (P<0.05),the content of TC, LDL-C, ApoE didn’t change(P>0.05); The degree of neuronal cells in hippocampal CA1region of group Ml, M2, M3destroyed were gradually serious.2. The linear regression analyses results of rats fed with high-fat showed that the content of brain TG had positive correlation with serum and liver TC, TG, LDL-C, but negative correlation with serum HDL-C, liver HDL-C and brain HDL-C. It had no correlation with brain TC or LDL-C; the brain TG content had positive correlation with serum24HyC, brain LDLR and24HyC; the brain HDL-C content had negative correlation with serum and liver TC, TG, LDL-C and brain TG, but positive correlation with serum and liver HDL-C, and it had no correlation with brain TC, LDL-C. The results also showed that the brain HDL-C content had negative correlation with serum24HyC, brain LDLR and24HyC. The content of brain TG and HDL-C had no correlation with serum ApoE, LDLR, liver ApoE, LDLR,24HyC and brain ApoE.3. The linear regression analyses results of rats fed with high-fat showed that brain LDLR had positive correlation with serum TC, TG, LDL-C, LDLR and24HyC, negative correlation with serum HDL-C, and no correlation with serum ApoE. The results also showed that brain24HyC content had positive correlation with serum TC, TG, LDL-C and24HyC, negative correlation with serum HDL-C, and no correlation with serum LDLR and ApoE; the content of brain ApoE had no correlation with blood-lipoids and serum ApoE, LDLR,24HyC.Conclusion:1. The rats which fed with high-fat feed could rasise serum and hapatic lipid gradually, the LDLR,24HyC content of serum increased, the ApoE content of hapatic raised, The LDLR content of hapatic decreased firstly and than raised; The TG, LDLR,24HyC of brain increased gradually. The neuronal cells in hippocampal CA1region have large number of cells shrinksed, and some exoplasm cracked. Cells destroyed seriously, which showed that it is necessary to prevent hyperlipidemia from happening, and to interfere early.2. The brain TG content of hyperlipidimia rats increased with serum and liver TC, TG, LDL-C, as well as brain LDLR and24HyC, but it decreased when serum, liver and brain HDL-C increased. The brain HDL-C content decreased when serum and liver TC, TG, LDL-C, brain TG increased,but it increased when serum and liver HDL-C. When serum and brain24HyC, brain LDLR increased, the brain HDL-C content decreased.3. The brain LDLR content of hyperlipidimia rats increased with serum TC, TG, LDL-C, LDLR and24HyC, but it decreased when serum HDL-C increased. The brain24HyC content increased with serum TC, TG, LDL-C and24HyC, but it decreased when serum HDL-C increased.