Hypothalamus-Pituitary-Adrenal Axis

Walsh P, Aeling JL, Huff L, Weston WL. Hypothalamus-pituitary-adrenal axis suppression by superpotent topical steroids. J Am Acad Dermatol 1993 29(3) 501-3. 

In its acute stages, benzene toxicity appears to be due primarily to the direct effects of benzene on the central nervous system, whereas the peripheral nervous system appears to be the target following chronic low-level exposures. In addition, because benzene may induce an increase in brain catecholamines, it may also have a secondary effect on the immune system via the hypothalamus-pituitary-adrenal axis (Hsieh et al. 1988b). Increased metabolism of catecholamines can result in increased adrenal corticosteroid levels, which are immunosuppressive (Hsieh et al. 1988b). 

Benigni, F., Fantuzzi, G., Sacco, S., Sironi, M., Pozzi, P., Dinarello, C. A., Sipe, J. D., Poli, V., Cappelletti, M., and Paonessa, G. et al. (1996). Six different cytokines that share GP130 as a receptor subunit, induce serum amyloid A and potentiate the induction of interleukin-6 and the activation of the hypothalamus-pituitary-adrenal axis by interleukin-1. Blood 87, 1851-1854. 

Heine VM, Maslam S, Joels M, Lucassen PJ (2004) Prominent decline of newborn cell proliferation, differentiation, and apoptosis in the aging dentate gyrus, in absence of an age-related hypothalamus-pituitary-adrenal axis activation. Neurobiol Aging 25 361-375. 

Hypothalamus-pituitary-adrenal (HPA) Axis Circadian Rhythms Appetite Control Orexins... 

Corticotropin-releasing factor and arginine vasopressin, which are released predominantly by the paraventricular nucleus of the hypothalamus, are important regulators of corticotropin (ACTH) release, which in turn triggers the release of cortisol and other steroids by the adrenal gland. Both the administration of certain psychoactive agents and emotional arousal originating from the limbic system are able to modify the functions of the pituitary-adrenal axis and stimulate the synthesis of cortisol. 

The impact of administration of the toxin, however, is not confined to the immune system. It has recently been demonstrated that there are also quite significant changes induced in the endocrine (hormonal) and nervous systems and even behavioural changes. It has been shown that administration of SEB activates the hypothalamus-pituitary-adrenal (HPA) stress response axis,14 and that the challenge with SEB leads to the new behaviour of reduced consumption of mainly new foods or of food given in a new environment.15 The situation is even more complex because, as one recent review noted ... 

J. Licinio and P. Frost, The neuroimmune-endocrine axis pathophysiological implications for the central nervous system cytokines and hypothalamus-pituitary-adrenal hormone dynamics, Brazilian Journal of Medical and Biological Research, 33, 2000, 1141-8 Steinman (2004), note 46. 

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