The objective of this study was to analyze the mRNA transcription levels of ten functional genes of P-glycoproteins (P-gp) in free life stages, eggs and infective larvae (L₃) and in endoparasitic stages, fourth larval stage (L₄) and adult males of two native isolates of Haemonchus contortus: resistant and susceptible to IVM. The IVM resistant isolate was obtained from sheep naturally infected with H. contortus, and the susceptible isolate (with no pressure to IVM) conserved since 1990. The lethal effect of IVM was evaluated under in vitro conditions, which showed significant differences between susceptible and resistant H. contortus L₃ isolates (P < 0.01). The IVM susceptible isolate revealed a lethal effect of 79.22% at 11.42 mM, whereas that resistant isolate showed no lethal effect at any of the four assessed concentrations (1.43, 2.85, 5.71 and 11.42 mM) of IVM. The expression levels of ten Hco-pgp genes (1, 2, 3, 4, 9, 10, 11, 12, 14, and 16) were evaluated in the resistant isolate of H. contortus and compared to the susceptible isolate (as control), using two constitutive genes (GAPDH and β-tubulin). Up-regulation at two statistical significant values (P ≤ 0.05, 0.1) was the criterion to associate IVM resistance with the free life and endoparasitic stages of H. contortus. The expression levels in H. contortus adult nematodes showed 5.64 to 127.56-fold increase for Hco-pgp genes 1, 9, 12, 14, and 16, followed by an increase for Hco-pgp-2 (49.75-fold) and Hco-pgp-10 (106.40-fold) in L₄, and for Hco-pgp-16 (2.90-fold) in eggs (P ≤ 0.05). In addition, high expression levels with P < 0.1 were detected in H. contortus L₃, L₄, and adults for Hco-pgp genes 1, 4, 11, 12, and 16, with changes ranging from 2.17 to 29.72-fold. In conclusion, the highest expression was observed in the adult stage of H. contortus, and the most frequent gene with a significant P-value was Hco-pgp-16, revealing it plays an important role in IVM resistance.

这项研究的目的是分析自由生命阶段，卵和感染性幼虫（L ₃）以及内寄生虫阶段，第四幼虫阶段（L ₄）的十个P糖蛋白（P-gp）功能基因的mRNA转录水平。以及两种本地分离的捻转血矛线虫的成年男性：具有抗药性，易患IVM。IVM抗性分离株是从自然感染了Con。contortus的绵羊获得的，易感分离株（对IVM无压力）自1990年以来一直保存。在体外条件下评估了IVM的致死作用，表明易感性和抗性之间存在显着差异H. contortus L ₃分离株（P <0.01）。易受IVM影响的分离株在11.42 mM时显示出79.22％的致死率，而该抗性分离株在IVM的四个评估浓度（1.43、2.85、5.71和11.42 mM）中均未显示致死性。的10的表达水平HCO-PGP基因（1，2，3，4，9，10，11，12，14，和16）中的耐药株进行评价捻转血矛线虫，并与易感分离物（作为对照），使用两个组成性基因（GAPDH和β-微管蛋白）。上调在两个统计显著值（P ≤0.05，0.1）为标准，以与自由生活和内寄生阶段准IVM电阻捻转血矛线虫。中的表达水平捻转血矛线虫成人线虫表明5.64到127.56倍的增加为HCO-PGP基因1，9，12，14，和16，随后的增加为HCO-PGP-2（49.75倍）和HCO-PGP-10（ 106.40倍）以L ₄，和用于HCO-PGP-16在鸡蛋（（2.90倍）P ≤0.05）。此外，具有高表达水平P中检测到<0.1捻转血矛线虫大号₃，L ₄，和成人为HCO-PGP基因1，4，11，12，和16，变化范围为2.17到29.72倍。总之，在成年阶段观察到的最高表达捻转血矛线虫，而最常见的基因有显著P -值是HCO-PGP-16，揭示它在IVM性具有重要作用。