Stress is a general adaptive reaction crucial for survival and basically positive that involves the neuroendocrine and the immune systems. In all bilaterian metazoans, the molecular mediators of the stress response, i.e., corticotrophin-releasing hormone, corticotrophin, catecholamines and glucocorticoids, have been preserved during evolution, even if the increased complexity of animals have corresponded to a more articulated stress response that, following the eco-immunology perspective, we speculate to be hierarchically organized along three levels.
Around the word stress: its biological and evolutive implications / Ottaviani, Enzo; Malagoli, Davide. - In: INVERTEBRATE SURVIVAL JOURNAL. - ISSN 1824-307X. - ELETTRONICO. - 6:1(2009), pp. 1-6.