Acharya D P, Sen M R, Sen P C
Indian J Exp Biol. 1989 Aug;27(8):718-20.
In an effort to find out the mechanism(s) operative in enhancing the pathogenicity of E. histolytica in hosts under heat stress reported earlier, effect of 5-hydroxytryptamine (5-HT) on the virulence of the parasite was examined in just weaned Charles Foster strain of albino rats. Pathogenicity of 10 strains of E. histolytica, from various forms of intestinal amoebiasis, grown in modified Boeck and Drbohlav's medium was assessed by caecal scoring. Administration of 5-HT in infected animals significantly enhanced the pathogenicity of all the seven strains tested. Treatment of the host with the 5-HT precursor L-tryptophan also increased the caecal scores examined with three strains of E. histolytica. Prior blocking of tissue 5-HT receptors by administration of methysergide almost completely abolished the pathogenicity enhancing effect of 5-HT treatment. This suggested that 5-HT itself and not any of its metabolites was responsible for the observed increase in pathogenicity of E. histolytica on 5-HT treatment of the host.
为了弄清楚先前报道的在热应激宿主中增强溶组织内阿米巴致病性的作用机制，在刚断奶的白化大鼠查尔斯·福斯特品系中检测了5-羟色胺（5-HT）对该寄生虫毒力的影响。通过盲肠评分评估了在改良的伯克和德博赫拉夫培养基中培养的10株来自各种肠道阿米巴病形式的溶组织内阿米巴的致病性。给感染动物施用5-HT显著增强了所有7株受试菌株的致病性。用5-HT前体L-色氨酸处理宿主也增加了用3株溶组织内阿米巴检测的盲肠评分。通过施用麦角酰二乙胺预先阻断组织5-HT受体几乎完全消除了5-HT处理的致病性增强作用。这表明是5-HT本身而非其任何代谢产物导致了宿主经5-HT处理后溶组织内阿米巴致病性的增加。
