Laboratório de Comportamento e Fisiologia Evolutiva, Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.
J Exp Zool A Ecol Integr Physiol. 2017 Feb;327(2-3):127-138. doi: 10.1002/jez.2078. Epub 2017 Jun 28.
Stressors can increase plasma glucocorticoid (GC) levels and decrease plasma androgen levels in different species of vertebrates. GCs can have immune-enhancing or immunosuppressive effects, which are dependent upon stress duration and intensity. The worldwide decline in amphibian populations is strongly linked to an array of different stressors. The impacts of stress on GCs, androgens, and the immune response are important to clarify and should lead to the better development of conservation strategies. The present study in adult male toads of Rhinella schneideri investigated the effects of captivity (7, 30, and 60 days) on plasma corticosterone (CORT) and plasma testosterone (T), as well as innate immune responses, specifically humoral and cell mediated responses, as indicated by bacterial killing ability (BKA) and phagocytosis by peritoneal cells, respectively. Captivity increased CORT threefold and decreased T versus controls. CORT maintained a threefold elevation throughout the captivity period, while body mass and T gradually decreased with time in captivity. BKA was lower at day 30, versus days 7 and 60, while peritoneal cell phagocytic efficiency decreased after day 30, remaining low at day 60. Moreover, phagocytosis efficiency was positively associated with T and body condition, suggesting that the effects of chronic stress on reproductive potential and immune response might be associated with the state of energetic reserves.
应激原可以增加不同脊椎动物种类的血浆糖皮质激素（GC）水平并降低血浆雄激素水平。GC 具有免疫增强或免疫抑制作用，这取决于应激的持续时间和强度。两栖动物种群在全球范围内的下降与一系列不同的应激原密切相关。阐明应激对 GC、雄激素和免疫反应的影响非常重要，这将有助于制定更好的保护策略。本研究以成年雄性蟾属 Rhinella schneideri 为研究对象，调查了圈养（7、30 和 60 天）对血浆皮质酮（CORT）和血浆睾酮（T）以及先天免疫反应（分别通过细菌杀伤能力（BKA）和腹腔细胞吞噬作用来表示的体液和细胞介导的反应）的影响。圈养使 CORT 增加了三倍，T 则降低了。CORT 在整个圈养期间保持三倍升高，而体重和 T 随着圈养时间的增加而逐渐下降。BKA 在第 30 天与第 7 天和第 60 天相比降低，而腹腔细胞吞噬效率在第 30 天后下降，第 60 天仍较低。此外，吞噬效率与 T 和身体状况呈正相关，这表明慢性应激对生殖潜力和免疫反应的影响可能与能量储备状态有关。
