depression in the animal model. Of potential clinical relevance, the researchers identified links between the occurrence of anhedonia and significant changes in levels of cytokine and stress hormones (e.g., corticosterone) in the rats' blood plasma. Grippo and her colleagues have also conducted research on social isolation in relation to anxiety and depression in prairie vole, and associated disturbances in neuroendocrine activation that may be of clinical importance for understanding cardiovascular complications associated with stress. One of her studies investigated the hypothesis that social and environmental stressors, including long term social isolation, may alter the expression of gap junction proteins, Connexin 43 and Connexin 45. These proteins, located in the heart, play an important role in cardiac rhythmicity and intercellular communication. In this study, socially isolated prairie voles exhibited depressive behavior as compared to a control group (living in pairs). Social isolation was also found to alter the expression of Connexin 43 in the left ventricle of the heart, thus elucidating possible cellular mechanisms underlying altered cardiac rhythmicity in response to stress. Representative publications Grippo, A. J., Francis, J., Beltz, T. G., Felder, R. B., & Johnson, A. K. (2005). Neuroendocrine and cytokine profile of chronic mild stress-induced anhedonia. Physiology & Behavior, 84(5), 697–706. Grippo, A. J., Gerena, D., Huang, J., Kumar, N., Shah, M., Ughreja, R., & Carter, C. S. (2007). Social isolation induces behavioral and neuroendocrine disturbances relevant to depression in female and male prairie voles. Psychoneuroendocrinology, 32(8-10), 966–980. Grippo, A. J., & Johnson, A. K. (2002). Biological mechanisms in the relationship between depression and heart disease. Neuroscience & Biobehavioral Reviews, 26(8), 941–962. Grippo, A. J., & Johnson, A. K. (2009). Stress, depression and cardiovascular dysregulation: a review of neurobiological mechanisms and the integration of research from preclinical disease models. Stress, 12(1), 1-21. Grippo, A. J., Trahanas, D. M., Zimmerman II, R. R., Porges, S. W., & Carter, C. S. (2009). Oxytocin protects against negative behavioral and autonomic consequences of long-term social isolation. Psychoneuroendocrinology, 34(10), 1542–1553. References External links Faculty page Research lab American women psychologists 21st-century American psychologists Northern Illinois University faculty Drake University alumni University of Iowa alumni Living people Year of birth missing (living people) American women academics 21st-century American women