Cooper Allen M, Fox Gerad A, Nelsen David R, Hayes William K
Department of Earth and Biological Sciences, Griggs Hall #101, Loma Linda University, 24941 Stewart St., Loma Linda, CA 92350, USA.
Department of Earth and Biological Sciences, Griggs Hall #101, Loma Linda University, 24941 Stewart St., Loma Linda, CA 92350, USA.
Toxicon. 2014 May;82:30-51. doi: 10.1016/j.toxicon.2014.02.003. Epub 2014 Feb 16.
Venom generally comprises a complex mixture of compounds representing a non-trivial metabolic expense. Accordingly, natural selection should fine-tune the amount of venom carried within an animal's venom gland(s). The venom supply of scolopendromorph centipedes likely influences their venom use and has implications for the severity of human envenomations, yet we understand very little about their venom yields and the factors influencing them. We investigated how size, specifically body length, influenced volume yield and protein concentration of electrically extracted venom in Scolopendra polymorpha and Scolopendra subspinipes. We also examined additional potential influences on yield in S. polymorpha, including relative forcipule size, relative mass, geographic origin (Arizona vs. California), sex, time in captivity, and milking history. Volume yield was linearly related to body length, and S. subspinipes yielded a larger length-specific volume than S. polymorpha. Body length and protein concentration were uncorrelated. When considering multiple influences on volume yield in S. polymorpha, the most important factor was body length, but yield was also positively associated with relative forcipule length and relative body mass. S. polymorpha from California yielded a greater volume of venom with a higher protein concentration than conspecifics from Arizona, all else being equal. Previously milked animals yielded less venom with a lower protein concentration. For both species, approximately two-thirds of extractable venom was expressed in the first two pulses, with remaining pulses yielding declining amounts, but venom protein concentration did not vary across pulses. Further study is necessary to ascertain the ecological significance of the factors influencing venom yield and how availability may influence venom use.
毒液通常由多种化合物组成的复杂混合物构成，这意味着其代谢成本不容小觑。因此，自然选择应该会精确调节动物毒腺中所携带的毒液量。蚰蜒目蜈蚣的毒液供应量可能会影响它们对毒液的使用，并且对人类被蜇伤的严重程度有影响，然而我们对它们的毒液产量及其影响因素却知之甚少。我们研究了体型，特别是体长，如何影响多棘蜈蚣和少棘蜈蚣电刺激提取毒液的体积产量和蛋白质浓度。我们还研究了对多棘蜈蚣产量的其他潜在影响因素，包括颚足相对大小、相对体重、地理来源（亚利桑那州与加利福尼亚州）、性别、圈养时间和采毒历史。体积产量与体长呈线性关系，少棘蜈蚣的单位体长毒液产量比多棘蜈蚣更大。体长与蛋白质浓度不相关。在考虑对多棘蜈蚣体积产量的多种影响因素时，最重要的因素是体长，但产量也与颚足相对长度和相对体重呈正相关。在其他条件相同的情况下，来自加利福尼亚州的多棘蜈蚣比来自亚利桑那州的同种蜈蚣产生的毒液量更大，蛋白质浓度更高。之前采过毒的动物产生的毒液量更少，蛋白质浓度更低。对于这两个物种，大约三分之二的可提取毒液在前两个脉冲中分泌，其余脉冲分泌量逐渐减少，但毒液蛋白质浓度在各脉冲间没有变化。有必要进一步研究以确定影响毒液产量的因素的生态意义以及毒液供应量如何影响毒液的使用。
