Klein S L, Taymans S E, DeVries A C, Nelson R J
Department of Psychology, Johns Hopkins University, Baltimore, Maryland 21218-2686, USA.
Am J Physiol. 1996 Dec;271(6 Pt 2):R1608-13. doi: 10.1152/ajpregu.1996.271.6.R1608.
Glucocorticoids compromise immune function in glucocorticoid-sensitive species (e.g., mice), but these immunosuppressive effects may be reduced in glucocorticoid-resistant species. Prairie voles (microtus ochrogaster) have been characterized as glucocorticoid-resistant to their high circulating levels of corticosterone. Because glucocorticoid-sensitive species display suppressed lymphocyte proliferation in response to elevated blood glucocorticoid levels, proliferative values were hypothesized to be reduced in house mice (Mus musculus) compared with prairie voles. Prairie voles exhibited significantly higher splenocyte proliferative responses to the T cell mitogen, Concanavalin A, despite having higher basal total and free serum corticosterone levels than mice. Neither total nor free serum corticosterone correlated with proliferative responses from either species. These data provide further evidence for glucocorticoid resistance in prairie voles and suggest that the interactions between the hypothalamic-pituitary-adrenal axis and the immune system in prairie voles may differ from those in mice or other glucocorticoid-sensitive species. Therefore, prairie voles may serve as a valuable animal model for the syndrome of glucocorticoid resistance in humans and the role of glucocorticoids in conditions characterized by a hyperactive immune system.
糖皮质激素会损害糖皮质激素敏感物种（如小鼠）的免疫功能，但在糖皮质激素抵抗物种中，这些免疫抑制作用可能会减弱。草原田鼠（Microtus ochrogaster）因其循环中高水平的皮质酮而被认为具有糖皮质激素抵抗性。由于糖皮质激素敏感物种在血液糖皮质激素水平升高时会表现出淋巴细胞增殖受到抑制，因此推测家鼠（Mus musculus）的增殖值与草原田鼠相比会降低。尽管草原田鼠的基础总血清皮质酮和游离血清皮质酮水平高于小鼠，但它们对T细胞有丝分裂原刀豆球蛋白A的脾细胞增殖反应显著更高。两种物种的血清总皮质酮和游离皮质酮均与增殖反应无关。这些数据为草原田鼠的糖皮质激素抵抗提供了进一步证据，并表明草原田鼠下丘脑-垂体-肾上腺轴与免疫系统之间的相互作用可能与小鼠或其他糖皮质激素敏感物种不同。因此，草原田鼠可能成为研究人类糖皮质激素抵抗综合征以及糖皮质激素在免疫系统亢进疾病中作用的有价值动物模型。
