Reduced hippocampal MT2 melatonin receptor expression in Alzheimer's disease

The aim of the present study was to identify the distribution of the second melatonin receptor (MT2) in the human hippocampus of elderly controls and Alzheimer's disease (AD) patients. This is the first report of immunohistochemical MT2 localization in the human hippocampus both in control and AD cases. The specificity of the MT2 antibody was ascertained by fluorescence microscopy using the anti-MT2 antibody in HEK 293 cells expressing recombinant MT2, in immunoblot experiments on membranes from MT2 expressing cells, and, finally, by immunoprecipitation experiments of the native MT2.MT2 immunoreactivity was studied in the hippocampus of 16 elderly control and 16 AD cases. In controls, MT2 was localized in pyramidal neurons of the hippocampal subfields CA1-4 and in some granular neurons of the stratum granulosum. The overall intensity of the MT2 staining was distinctly decreased in AD cases. The results indicate that MT2 may be involved in mediating the effects of melatonin in the human hippocampus, and this mechamism may be heavily impaired in AD

Frontocortical N-acetylaspartate reduction associated with long-term iv heroin use

To examine possible metabolic frontal lobe alterations in i.v. heroin-dependent patients with different histories of concomitant substance use, N-acetylaspartate (NAA), a putative marker of neuronal viability, was measured by (1)H-MRS. Compared with controls, NAA levels in patients were reduced by 7% in gray matter (p = 0.015) but not in white matter. To what extent comorbid conditions or substance use, including alcohol, contributed to these frontocortical metabolic changes remains to be elucidated

World Health Organization/International Society for Biomedical Research on Alcoholism study on state and trait markers of alcohol use and dependence: Back to the future

This article summarizes content proceedings of a symposium held at the 2004 International Society for Biomedical Research on Alcoholism Congress in Mannheim, Germany. The chairs were Boris Tabakoff and Friedrich M. Wurst. The presentations were (1) Genetic associations with alcoholism and affective disorders, by Paula Hoffman; (2) Proteomic analysis of blood constituents in alcoholism, by Boris Tabakoff; (3) Contrasts between the responses of GGT and CDT to high alcohol intake, and a test of their combined use, by John Whitfield; (4) Direct ethanol metabolites such as ethyl glucuronide, fatty acid ethyl esters, phosphatidylethanol and ethyl sulfate: a new line of sensitive and specific biomarkers, by Friedrich Martin Wurst; and (5) Genetic studies of alcoholism subtypes in a Han Taiwanese population, by Ru-Band Lu