Cavigelli Sonia A, Bennett Jeanette M, Michael Kerry C, Klein Laura Cousino
Biobehavioral Health Department, 315 Health & Human Development-East, Pennsylvania State University, University Park, PA 16802, USA.
Brain Behav Immun. 2008 Jul;22(5):727-35. doi: 10.1016/j.bbi.2007.10.014. Epub 2007 Dec 21.
Behavioral characteristics closely associated with specific physiological profiles present an important area of research in understanding health disparities. In particular, glucocorticoid overproduction may be an important factor moderating disease progression; natural variance in production of this steroid has been proposed as one mechanism underlying individual differences in health and disease. In the current paper, we examined immune parameters in female rats of two different behavioral types previously shown to have differential glucocorticoid production and life spans. We categorized young female rats according to their behavioral response to novelty (high- or low-locomotion), and compared their glucocorticoid production, adrenal size, thymus size, tumor necrosis factor-alpha (TNF-alpha) production, tumor development and life span. As expected, high-locomotion females produced more glucocorticoids and had larger adrenal glands during young adulthood than did low-locomotion females. High-locomotion females had significantly smaller thymuses and reduced TNF-alpha levels compared to low-locomotion, suggesting altered immune function in young adulthood. Finally, high-locomotion females had shorter life spans than did low-locomotion females, and this was particularly true in females that developed pituitary tumors, but not in those that developed mammary tumors. These results, along with other published findings, suggest that high-locomotion rodent females experience life-long elevations in glucocorticoid responses to novelty, and that these elevated levels may be comparable to chronic stress. This naturally occurring endocrine profile may influence immune responses which in turn could affect disease susceptibility. Variance in immune function across personality types may be partially moderated by natural variance in glucocorticoid production.
与特定生理特征密切相关的行为特征是理解健康差异的一个重要研究领域。特别是，糖皮质激素分泌过多可能是调节疾病进展的一个重要因素；这种类固醇分泌的自然差异被认为是健康和疾病个体差异的一种潜在机制。在本文中，我们研究了两种不同行为类型的雌性大鼠的免疫参数，这两种行为类型先前已被证明具有不同的糖皮质激素分泌量和寿命。我们根据幼年雌性大鼠对新事物的行为反应（高运动量或低运动量）对其进行分类，并比较了它们的糖皮质激素分泌量、肾上腺大小、胸腺大小、肿瘤坏死因子-α（TNF-α）分泌量、肿瘤发生情况和寿命。正如预期的那样，在成年早期，高运动量的雌性大鼠比低运动量的雌性大鼠分泌更多的糖皮质激素，肾上腺也更大。与低运动量的雌性大鼠相比，高运动量的雌性大鼠胸腺明显更小，TNF-α水平降低，这表明成年早期免疫功能发生了改变。最后，高运动量的雌性大鼠寿命比低运动量的雌性大鼠短，在发生垂体肿瘤的雌性大鼠中尤其如此，但在发生乳腺肿瘤的雌性大鼠中并非如此。这些结果以及其他已发表的研究结果表明，高运动量的啮齿动物雌性对新事物的糖皮质激素反应会终生升高，而且这些升高的水平可能与慢性应激相当。这种自然发生的内分泌特征可能会影响免疫反应，进而可能影响疾病易感性。不同性格类型之间免疫功能的差异可能部分受到糖皮质激素分泌自然差异的调节。
