Division of Biomedical Sciences, St George's University of London, Cranmer Terrace, London, SW17 0RE UK ; King's College London-Centre for Molecular and Cellular Biology of Inflammation, New Hunt's House, Great Maze Pond, London, SE1 1UL UK.
Division of Biomedical Sciences, St George's University of London, Cranmer Terrace, London, SW17 0RE UK.
Zoological Lett. 2016 Mar 29;2:8. doi: 10.1186/s40851-016-0044-5. eCollection 2016.
Octopoda utilise their arms for a diverse range of functions, including locomotion, hunting, defence, exploration, reproduction, and grooming. However the natural environment contains numerous threats to the integrity of arms, including predators and prey during capture. Impressively, octopoda are able to close open wounds in an aquatic environment and can fully regenerate arms. The regrowth phase of cephalopod arm regeneration has been grossly described; however, there is little information about the acute local response that occurs following an amputation injury comparable to that which frequently occurs in the wild.
Adult Octopus vulgaris caught in the Bay of Naples were anaesthetised, the distal 10 % of an arm was surgically amputated, and wounded tissue was harvested from animals sacrificed at 2, 6, and 24 h post-amputation. The extent of wound closure was quantified, and the cell and tissue dynamics were observed histologically, by electron microscopy, as well as using ultrasound.
Macroscopic, ultrasonic and ultrastructural analyses showed extensive and significant contraction of the wound margins from the earliest time-point, evidenced by tissue puckering. By 6 h post amputation, the wound was 64.0 ± 17.2 % closed compared to 0 h wound area. Wound edge epithelial cells were also seen to be migrating over the wound bed, thus contributing to tissue repair. Temporary protection of the exposed tip in the form of a cellular, non-mucus plug was observed, and cell death was apparent within two hours of injury. At earlier time-points this was apparent in the skin and deeper muscle layers, but ultimately extended to the nerve cord by 24 h.
This work has revealed that O. vulgaris ecologically relevant amputation wounds are rapidly repaired via numerous mechanisms that are evolutionarily conserved. The findings provide insights into the early processes of repair preparatory to regeneration. The presence of epithelial, chromatophore, vascular, muscle and neural tissue in the arms makes this a particularly interesting system in which to study acute responses to injury and subsequent regeneration.
章鱼的腕足具有多种功能，包括运动、捕食、防御、探索、繁殖和清洁等。然而，自然环境中存在许多威胁腕足完整性的因素，包括捕食者和猎物在捕猎时的伤害。令人惊讶的是，章鱼能够在水生环境中闭合开放性伤口，并能完全再生腕足。头足类腕足再生的再生阶段已经被粗略描述；然而，关于在野外经常发生的截肢损伤后发生的急性局部反应的信息很少。
在那不勒斯湾捕获的成年普通章鱼被麻醉，手术切除腕足的远端 10%，并从截肢后 2、6 和 24 小时处死的动物中采集受伤组织。通过定量测量伤口闭合的程度，以及组织学、电子显微镜和超声检查观察细胞和组织动态。
宏观、超声和超微结构分析显示，从最早的时间点开始，伤口边缘就出现了广泛而显著的收缩，表现为组织皱缩。截肢后 6 小时，伤口闭合度为 64.0±17.2%，与 0 小时伤口面积相比。还观察到伤口边缘上皮细胞向伤口床迁移，从而促进组织修复。在暴露的尖端处暂时形成了一种细胞非黏液塞，以提供临时保护，受伤后两小时内观察到细胞死亡。在较早的时间点，这种情况在皮肤和更深的肌肉层中很明显，但最终在 24 小时内延伸到神经索。
这项工作表明，生态相关的章鱼截肢伤口通过多种进化上保守的机制迅速修复。这些发现为再生前修复的早期过程提供了见解。章鱼的腕足中存在上皮细胞、色素细胞、血管、肌肉和神经组织，这使得该系统成为研究急性损伤反应和随后再生的一个特别有趣的系统。
