SIMILAR AGE-RELATED INCREASE OF VASOPRESSIN COLOCALIZATION IN PARAVENTRICULAR CORTICOTROPIN-RELEASING HORMONE NEURONS IN CONTROLS AND ALZHEIMER PATIENTS

Recent studies on experimental animals showed that long term activation of the hypothalamo-pituitary-adrenal axis is associated with increased vasopressin (AVP) colocalization in paraventricular corticotropin-releasing hormone (CRH) neurons. In the present study we estimated the fraction of CRH neurons in which AVP is colocalized by double label immunocytochemistry in hypothalami of 10 control subjects of 21-91 years of age and 10 age-matched Alzheimer patients. CRH neurons in the paraventricular nucleus (PVN) of Alzheimer patients and control subjects showed similar age dependent increases in AVP colocalization. Based on this parameter, it seems that CRH neurons of Alzheimer patients are not overactivated as compared to age-matched controls, but e.g. changes in m-RNA for CRH should still be established.