Fiorito P, Burgos J M, Miyakawa M F, Rivas M, Chillemi G, Berkowski D, Zotta E, Silberstein C, Ibarra C
Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Argentina.
Dig Dis Sci. 2000 Mar;45(3):480-6. doi: 10.1023/a:1005480720832.
Shiga toxin-producing Escherichia coli (STEC) colonize the lower segments of the human gastrointestinal tract, causing gastrointestinal and systemic diseases. In this study, the effects of Shiga toxin 2 (Stx2) on fluid absorption and ion transport in the human colon were examined. Net water movement (Jw) and short-circuit current (Isc) were simultaneously measured across the colonic mucosa incubated with crude or purified Stx2. Stx2 significantly inhibited the absorptive J(w) with no effect on the basal I(sc) after 60 min of exposure. These effects may be due to the inhibition of a nonelectrogenic transport system present in the surface colonic villus cells. Morphological studies of the colonic mucosa treated with crude or purified Stx2 demonstrated a selective damage in the absorptive villus epithelial cells. These findings suggest that Stx2 inhibits water absorption across the human colon by acting on a specific cell population: the mature, differentiated absorptive villus epithelium.
产志贺毒素大肠杆菌（STEC）定殖于人类胃肠道下段，可引发胃肠道疾病和全身性疾病。在本研究中，检测了志贺毒素2（Stx2）对人结肠中液体吸收和离子转运的影响。在与粗制或纯化的Stx2共同孵育的结肠黏膜上同时测量净水流（Jw）和短路电流（Isc）。暴露60分钟后，Stx2显著抑制吸收性J(w)，而对基础I(sc)无影响。这些作用可能是由于抑制了结肠绒毛表面细胞中存在的非电转运系统。对用粗制或纯化的Stx2处理的结肠黏膜进行的形态学研究表明，吸收性绒毛上皮细胞存在选择性损伤。这些发现表明，Stx2通过作用于特定细胞群体：成熟、分化的吸收性绒毛上皮，来抑制人结肠的水吸收。
