Relationship between Serum Uric Acid Levels and Kidney Arteriole Resistance in Patients with Type 2 Diabetes Associated with Hypertension

Objectives To investigate the relationship between serum uric acid levels and arteriole resistance detected with the color Doppler energy imaging (CDEI) and to explore the risks of impaired regulation of vascular tone by uric acid in kidneys of hypertension patients. Methods In 12 healthy control cases, 28 non-diabetic hypertension (nNIDDM +H) cases and 25 type 2 diabetic hypertension (NIDDM+H) cases, uric acid (UA) levels were measured with uricase-peroxidase method. Arteriole resistance index (RI) and pulsate index (PI) in separate sections of renal artery included MAR, SRA, IRA were detected using CDEI with 2.1~4.2 Hz Doppler transducer in kidneys. Results In comparison, UA was significantly higher in non-diabetic hyper- tension group and diabetic hypertension group than in control group (P<0.01, separately). UA levels was also significantly higher in NIDDM+H group than in nNIDDM+H, P < 0.029. RI in separate sections of renal artery was significantly higher in nNIDDM+H, or NIDDM+H group than in control group ( all P < 0.01) , and it was significantly higher in NIDDM +H than nNIDDM+H groups (P < 0.05 and P < 0.01). In nNIDDM +H and NIDDM +H groups UA levels and IRA-RI could be elevated significantly following with the impaired heart function being aggravated (χ2 = 13.028, P=0.005, χ2=13.29, P=0.004); the dosage of HCT being increased (χ2 =14.216, P=0.001, χ2 = 14.661, P=0.001); the levels of GHbA1 being excessed unnormally (P=0.000). The correlation between UA and IRA-RI in both hypertension groups were directly related, in nNIDDM+H group r=0.842, P=0.000, in NIDDM+H group, r=0.797, P=0.000. Conclusions Uric acid levels and IRA-RI in hyper-tension patients were directly related. Uric acid levels and IRA-RI could be partly dependent on the severity of heart dysfunction, diuretic dose, and serum glucose status of diabete patients in long-term. Uric acid and the xanthine oxidase metabolic pathway may contribute to impaired regulation of arteriole tone in hypertension patients.

All-TRANS RETINOIC ACID INTERFERES DEVELOPMENT OF PULMONARY HYPERTENSION INDUCED BY MONOCROTALINE IN RATS

Objective To determine whether all-trans retinoic acid (atRA) affects the metabolism of collagen in main pulmonary artery and exerts an inhibitory effect in rats with pulmonary hypertension induced by monocrotaline. Methods All rats (n = 72) were divided into 3 groups as control, model, and atRA. in model and atRA groups, rats (n =48) were assigned at random to be given a single subcutaneous injection of monocrotaline (60mg/kg) and administrated with either atRA (30mg· kg-1·d-1) for atRA group or saline through oral-gastro intubation for model group. in control group, rats (n =24) received a single subcutaneous injection of an equal volume of 0. 9% saline. On day 7, 14, 21 and 28 after monocrotaline or saline injection, cardiovascular catheters were inserted into the pulmonary artery of rats in each group to examine their mean pulmonary artery pressure, in addition with their hydroxyproline content determined by chromometry. Results In comparison with the control rats, the mean pulmonary artery p ressure of rats in model group in-creased significantly on day 21 and up to the peak on day 28 (P <0. 01), while their hydroxyproline contents decreased significantly on day 14 (P< 0. 05) and increased significantly on day 21 and 28. The atRA group when compared with the model group show reduction in the content of hydroxyproline and the mean pulmonary artery pressure (P < 0. 01). Conclusion The atRA inhibits the accumulation of collagen in main pul-monary artery and interferes the development of pulmonary hypertension which might elicit favorable geometric remodeling of rat pulmonary hypertension induced by monocrotaline.

The association between paired basic amino acid cleaving enz yme 4 gene haplotype and diastolic blood pressure

Background In a previously identified locus linked to hypertension on chromosome 15q, we identified three blood pressure candidate genes: insulin-like growth factor 1 receptor gene (IGF1R), myocyte specific enhancer factor 2A gene (MEF2A), and paired basic amino acid cleaving enzyme 4 gene (PACE4). In this study, we te sted their associations with hypertension using haplotype analysis.Methods A total of 288 unrelated individuals, including 163 high diastolic blood pressure (DBP) subjects and 125 normal DBP subjects were enrolled in this case-control study. Twenty single nucleotide polymorphisms (SNPs) in the three genes were genotyped using polymerase chain reaction followed by restriction enzyme digestion. Haplotype analysis was accomplished in the following stages: (1) pair-wise linkage disequilibrium test among SNPs on the same gene was performed to explore blocks in which recombination is very unlikely to happen; (2) Estimation-Maximization algorithm was applied to estimate haplotype frequencies in each block; (3) the chi-square test was used to examine the specific haplotype difference, and a permutation test was used to examine the overall haplotype profile difference between cases and controls in each block.Results An estimated haplotype “CCCCG” frequency in the haplotype block on the PACE4 gene was significantly higher in high DBP cases than in controls (P<0.01). The overall estimated haplotype profile in this block was also significantly different between the cases and the controls (P<0 .001). This association indicates. Conclusions This study for the first time demonstrated that PAC E4 gene may play an important role in the regulation of DBP. This association indicates that variations influencing DBP resides in or near this genomic region.

Effect of Zhongfeng Naodeping Granule on Hippocampal Excitatory Amino Acid and Neuron of Stroke-Prone Spontaneously Hypertensive Rats with Hemorrhagic Apoplexy

Objective: To observe the effects ofZhongfeng Naodeping Granule (ZFNDPG) onhemorrhagic apoplexy. Methods: The strokeprone spontaneously hypertensive rats(SHRsp ) were used to study effects ofZFNDPG on hemorrhage apoplexy. Excitatoryamino acid (EAA) concentration in hippocampus sector, neuronal density and ultrastructural changes in hippocampal CAI sector weremeasured. Results: In pathological modelgroup glutamate (Gin) and aspartate (Asp)concentration elevated obviously. With theZFNDPG treating SHRsp of hemorrhagicapoplexy, Gin and Asp concentration in hippocampal sector could be markedly inhibited,compared with model group, P < 0.05-0. 01. Neuronal morphology was observed:neurone injury was mild and neuronal densityincreased in hippocampal CA1 sector of treatment group, compared with model group, P< 0. 01. Electron microscopy showed t edema,degeneration and necrosis caused by hemorrhagic apoplexy were improved after theZFNDPG treatment. Conclusions: Effects ofprotecting neurone for SHRsp on hemorrhagicapoplexy might be associated with thatZFNDPG inhibited concentration of EAA.