BACKGROUND:Potassium channel is the main ion channel to regulate vascular smooth muscle contraction and relaxation, and closely related with vascular tone. However, the reports about the mechanism of potassium channels in the body’s aging process are rare. OBJECTIVE:To investigate the effects of aging on the arterial ultrastructure and smooth muscle potassium channel reaction, and then to explore the possible mechanisms. METHODS:Sixteen healthy male Wistar rats were col ected, 19-month-old rats were assigned to the old group (n=8), 2-month-old rats were used as young group (n=8). The thoracic arteries were isolated and cut into rings to conduct contractility measurement in six rats of each group. The thoracic arteries were stimulated with specific calcium-activated potassium channel blocker tetraethylammonium, specific voltage-dependent potassium channel blocker 4-aminopyridine, specific ATP-sensitive potassium channel blocker glibenclamide, and specific inward rectifier potassium channel blocker BaCl 2 ultrastructure changes under electron microscope. , and then the arterial contractile response to the blockers were observed. The thoracic arteries of the remaining two rats in each group were taken to observe the arterial RESULTS AND CONCLUSION:Compared with the young group, the ultrastructures of the thoracic aortic endothelial cells and smooth muscle cells were changed in the old group;KCI induced the maximum thoracic aortic contractile tension, and then recovered to the baseline tension, and the recovery time in the old group was significantly longer than that in the young group;al the four kinds of blockers could increase vascular tone, and the tetraethylammonium and 4-aminopyridine induced thoracic aortic contractile response in the old group was significantly lower than that in the young group;there was no significant difference in vasoconstriction induced by glibenclamide and BaCl 2 . Aging can induce arterial ultrastructure changes and declination of vasodilatation capacity, which may partly due to the decreasing of the potassium channels function in smooth muscle cells, especial y the calcium-activated potassium channel and inward rectifier potassium channel.

Objective To investigate the reliability of Pediatric Evaluation of Disability Inventory (PEDI) in China. Methods 21 children with cerebral palsy were assessed with PEDI by 2 raters respectively. The intrarater and interrater agreement was analyzed. The internal consistency of the PEDI was also calculated. Results The ICC of intrarater and interrater was 0.919～0.993. The Cronbach α was 0.9597～0.9711 in self care, 0.9569～0.9799 in mobility, 0.9419～0.9830 in social function.Conclusion PEDI is reliable and internal consistent.

Objective To assess vitamin D levels in eastern China by a standard measurement. Methods The data were from a 2014 Survey on the Prevalence in East China for Metabolic Diseases and Risk Factors-China data base. There were 12662 subjects included in this cross-sectional study from February 2014 to June 2016. We assessed the vitamin D levels of natural population by a standard classification in which serum 25-hydroxy vitamin D (25-OHD)<50 nmol/ L was defined as vitamin D deficiency. Results The average serum 25-OHD level was (40. 5 ± 12. 5)nmol/ L, and there were 80. 3% subjects who would be classified as vitamin D deficiency; The average serum 25-OHD level of women was significantly lower than that of men (P< 0. 05); The serum 25-OHD concentrations of the <30, 30-39, 40-49, 50-59, 60-69, ≥70 age groups were 37. 81(31. 98-43. 52)nmol/ L, 39. 46(33. 87-45. 72) nmol/ L, 41. 17(34. 10-48. 65) nmol/ L, 40. 67(34. 20-49. 02) nmol/ L, 44. 00 (35. 67-53. 93) nmol/ L, 44. 14 (34. 61-55. 85)nmol/ L for males, and 36. 86 (30. 52-43. 75) nmol/ L, 37. 11 (31. 68-43. 23) nmol/ L, 36. 94 (30. 72-43. 71) nmol/ L, 38. 42(32. 08-46. 41) nmol/ L, 38. 58(31. 04-46. 21) nmol/ L, 37. 31(29. 34-47. 17) nmol/ L for females in corresponding subgroups. Conclusion The prevalence of vitamin D deficiency of natural population in eastern China was common, the levels of vitamin D in women were lower than those of men. However, the vitamin D levels were tended to be increasing with the advance of age.