Hurd H, Strambi C, Beckage N E
Department of Biological Sciences, University of Keele, UK.
Parasitology. 1990 Jun;100 Pt 3:445-52. doi: 10.1017/s0031182000078744.
Metacestodes of Hymenolepis diminuta cause a perturbance of vitellogenesis in the intermediate host Tenebrio molitor. The reduction in host reproductive output associated with infection may be due to this pathophysiology. Many of these events are regulated by host juvenile hormone (JH). A comparison of the titre of JH and its rate of degradation in female control and parasitized 15-day-old insects has been made. Haemolymph from female beetles contained 1.27 pMol JH equivalents/100 microliters. No significant difference was associated with infection. Likewise, the activity of JH esterase in female haemolymph was not affected by infection. However, topical application of a JH analogue, methoprene, at the time of infection or 8 days post-infection reduced the significant accumulation of vitellogenin usually found in the haemolymph of females 12 days or more post-infection. These findings indicate that parasite-induced alteration of host vitellogenesis is not mediated via alteration in JH titres, although observations made after hormone supplementation suggest some form of interaction between the parasite and the host endocrine system.
微小膜壳绦虫的中绦期会导致中间宿主黄粉虫的卵黄生成紊乱。与感染相关的宿主生殖产出减少可能归因于这种病理生理状况。其中许多事件受宿主保幼激素（JH）调控。已对雌性对照昆虫和被寄生的15日龄昆虫体内JH的滴度及其降解速率进行了比较。雌性甲虫的血淋巴中含有1.27皮摩尔JH当量/100微升。感染与之无显著差异。同样，雌性血淋巴中JH酯酶的活性也不受感染影响。然而，在感染时或感染后8天局部施用JH类似物烯虫酯，可减少通常在感染后12天及以上雌性昆虫血淋巴中发现的卵黄蛋白原的显著积累。这些发现表明，寄生虫诱导的宿主卵黄生成改变并非通过JH滴度的改变介导，尽管在激素补充后所做的观察表明寄生虫与宿主内分泌系统之间存在某种形式的相互作用。
