Khan I, Collins S M
Intestinal Diseases Research Unit, McMaster University Medical Centre, Hamilton, Ontario, Canada.
Am J Physiol. 1993 Jun;264(6 Pt 1):G1160-8. doi: 10.1152/ajpgi.1993.264.6.G1160.
We used polymerase chain reaction (PCR) and Northern analysis to examine the effect of Trichinella spiralis infection on mRNA expression of sodium pump isoforms in rat intestine. 28S RNA was coamplified as an internal standard, and the abundance of the isoformic mRNA was expressed relative to 28S RNA. As assessed by PCR and Northern analysis, the alpha 1- and beta 1-subunits were expressed in the jejunum and ileum of noninfected control rats. However, in the jejunum the levels were suppressed after 24 h of infection. The suppression became maximal by day 6 and was reversed to normal by day 23 postinfection (PI). In contrast, no suppression was observed in the noninflamed ileum of infected rats. Further analysis revealed that alpha 1-mRNA was suppressed in jejunal mucosa by 89% and in longitudinal muscle-myenteric plexus by 62% but was not suppressed in circular muscle. Western blot analysis revealed a 61% decrease in the alpha 1-subunit protein in the mucosa and a 62% decrease in longitudinal muscle, whereas there was no change in the alpha 1-protein in circular muscle on day 6 PI. In contrast, marked (89%) suppression of beta 1-mRNA was observed only in the mucosa; there was no change in either circular or longitudinal muscle on day 6 PI. These results indicate that T. spiralis infection in the rat is accompanied by a significant decrease in the alpha 1-subunit of the sodium pump in longitudinal muscle. This reduction could result from altered regulation involving pretranslational changes.(ABSTRACT TRUNCATED AT 250 WORDS)
我们运用聚合酶链反应（PCR）和Northern分析来检测旋毛虫感染对大鼠肠道钠泵亚型mRNA表达的影响。以28S RNA作为内参共同扩增，亚型mRNA的丰度相对于28S RNA进行表达。通过PCR和Northern分析评估，α1和β1亚基在未感染的对照大鼠空肠和回肠中表达。然而，感染24小时后空肠中的水平受到抑制。这种抑制在感染后第6天达到最大程度，并在感染后第23天恢复正常。相比之下，在感染大鼠未发炎的回肠中未观察到抑制现象。进一步分析显示，α1 - mRNA在空肠黏膜中被抑制了89%，在纵行肌 - 肌间神经丛中被抑制了62%，但在环行肌中未被抑制。蛋白质印迹分析显示，感染后第6天，黏膜中α1亚基蛋白减少61%，纵行肌中减少62%，而环行肌中α1蛋白没有变化。相比之下，仅在黏膜中观察到β1 - mRNA有明显（89%）的抑制；感染后第6天，环行肌和纵行肌均无变化。这些结果表明，大鼠感染旋毛虫伴随着纵行肌中钠泵α1亚基的显著减少。这种减少可能是由于涉及翻译前变化的调节改变所致。（摘要截短于250字）
