Section on Endocrine Physiology

Head: Greti Aguilera Harwood

Our group focuses on the molecular mechanisms of the hypothalamic stress response. Research during the past year has provided novel information on the transcriptional regulation of corticotropin releasing hormone (CRH) and the physiological actions of vasopressin (VP) during chronic stress adaptation. The new findings, that potentiation of early transcriptional activation and late repression of the CRH gene by minor increases in cAMP explain the rapid regulation of CRH expression by the non-cAMP–dependent regulators norepinephrine and glutamate, which are the major neurotransmitters released in the paraventricular nucleus during stress. Against the conventional view, phosphorylation of the transcription factor CREB not sufficient for activation of CRH transcription but requires recruitment of additional factors. Concerning the effects of VP, new findings demonstrate novel roles for the prominent increases in vasopressinergic activity during chronic stress. In addition to minor effects modulating pituitary ACTH secretion, vasopressin was found to mediate mitogenic responses in the pituitary and antiapoptotic actions in the brain.

Resources

• Employee Listing
• E-Mail the Lab: Greti_Aguilera@nih.gov