[Establishment of two-dimensional electrophoresis system of caudal gland].

OBJECTIVE: To establish an effective separation system of 2-DE for the proteome of caudal gland, and provide foundation for revealing the mechanisms of histological development and pharmacological activities. METHOD: The total proteins of caudal gland were extracted by TCA/acetone precipitation, phenol extraction/methanol-ammonium acetate precipitation and trizol-base method respectively and separated by immobilized pH gradient (IPG) strips prior to SDS-PAGE. Loading protein sample size and isoelectric focusing conditions were optimized. The gels were stained with Coomassie brilliant blue, scanned and then analyzed using PDQuest 8.0 analysis software. RESULT: The total proteins of caudal gland extracted by trizol-base method were the highest quality and could meet the needs of 2-DE. With 300 microg of proteins loaded on 7 cm pH 3-10 IPG strip followed by isoelectric focusing program II ,a satisfying 2-DE profiles were obtained. The total number of disticted protein spots was 209 with the optimized system. CONCLUSION: A well-resolved 2-DE patterns of caudal gland were obtained by this optimized system. This method could be applied to prepare other similar tissue sample and 2-DE studies.

[Field observation on the effect of low-sodium and high-potassium salt substitute on blood pressure in the rural community-based population in China].

OBJECTIVE: To investigate the effect of commercial low-sodium and high-potassium salt substitutes on blood pressure in the rural community-based population in China. METHODS: We conducted a quasi-experiment on 411 adults, who were 30 to 60 years of age, in 2 rural communities from Laiwu city in Shandong province of China on data from blood pressure screening. The subjects were divided into 2 groups: high blood pressure (HBP) and non-HBP (NHBP). Both groups and their family members took a low-sodium and high-potassium salt substitute for 3 months to replace the normal salt in their bodies. Blood pressure (BP) and 24-hour urinary sodium and potassium were measured regularly in the 2 groups. RESULTS: There was a continuously decreasing trend for BP at the end of the first month. Three months later, the mean BP decreased by 7.4 mm Hg (1 mm Hg = 0.133 kPa, t = 10.096, P = 0.000) for SBP and 3.8 mm Hg (t = 8.017, P = 0.000) for DBP in the HBP group, when compared to a 1.2 mm Hg (t = 2.507, P = 0.007) decrease on SBP and 1.0 mm Hg (t = 2.987, P = 0.002) on DBP in the NHBP group. The mean urinary sodium had a decrease of 15.5 mmol/24 h (t = 1.803, P = 0.037), but the urinary potassium increased by 4.2 mmol/24 h (t' = 2.132, P = 0.018). The result of urinary sodium appeared to be as follows: potassium ratio (Na(+)/K(+)) decreased by 1.2 (t = 2.786, P = 0.003) in the HBP group. However, in NHBP group, the mean urinary sodium decreased by 1.7 mmol/24 h (t = 0.211, P = 0.417) and urinary potassium increased by 3.7 mmol/24 h (t' = 2.207, P = 0.015), together with the decrease of Na(+)/K(+) by 0.7 (t = 1.818, P = 0.036). CONCLUSION: Results from our study clearly demonstrated that the intake of low-sodium and high-potassium salt substitute could effectively reduce the BP with good compliance among adults in the rural community-based population in China. This was an effective but non-medical method to prevent and control the high blood pressure.