ACTIVATION OF THE HUMAN SUPRAOPTIC AND PARAVENTRICULAR NUCLEUS NEURONS WITH AGING AND IN ALZHEIMERS-DISEASE AS JUDGED FROM INCREASING SIZE OF THE GOLGI-APPARATUS

The supraoptic (SON) and paraventricular nucleus (PVN) of the human hy pothalamus produce vasopressin (AVP) and oxytocin (OXT). Since in thes e nuclei no cells are lost during aging or Alzheimer's Disease (AD), f actors are searched for which may be responsible for this remarkable s tability. Earlier work in both rat and human indicated that the peptid e synthesis of these neurons was activated in the oldest age groups as judged from increased neuronal and nuclear size and AVP plasma levels . The size of the Golgi Apparatus (GA) has proved to be a very sensiti ve parameter for the synthetic activity of these neurosecretory cells in animal experiments. In order to determine changes in the GA during aging and in Alzheimer's Disease, we applied a polyclonal antiserum ag ainst immunoaffinity purified MG-160, a sialoglycoprotein of the media l cisternae of the GA, on formalin-fixed and paraffin-embedded section s of the SON and PVN of patients ranging in age from 29 to 97 years. H owever, our standard fixation procedure masked antigenic sites resulti ng in a minimal immunocytochemical staining in most of the tissues exa mined. It appeared to be possible, however, to retrieve the antigen an d to obtain an excellent staining of the GA by heating sections in a m icrowave oven before immunostaining. Following this procedure, an incr ease in size and intensity of the GA became apparent in individuals fr om about 70 years and older. In AD patients a similar increase in size and intensity of the immunostained GA was observed. Taken together, t hese results indicate that SON and PVN neurons are activated during th e course of aging and also in AD and that this activation takes place at an earlier age then observed previously by other cellular parameter s.