Concordant with the adrenergic-cholinergic imbalance hypothesis of affective psychosis, there is a cholinergic supersensitivity in depression. Thus, the anticholinergic properties of some antidepressants might contribute to their efficacy. However, in the present double-blind studies (n = 20) with mianserin and viloxazine, respectively, which lack anticholinergic properties, adjunctive treatment with the anticholinergic biperiden versus placebo did not enhance the antidepressive efficacy. Therefore, we hypothesized that cholinergic supersensitivity might be linked to some possibly predisposing dimension of personality. Indeed, in healthy male volunteers (n = 11) the behavioral and cardiovascular sensitivity to physostigmine correlated significantly with "irritability" and "emotional lability" as well as with habitually passive strategies in stress coping. The rise in plasma cortisol and norepinephrine correlated with "retardation"; that of epinephrine with active coping. Thus, the cholinergic supersensitivity in affective psychoses might be linked to a personality dimension like stress sensitivity rather than to the diagnostic category itself.

Careful attention should be given to the role of iron in brain physiology, because tissue iron deficiency and iron overload represent prevalent metabolic disorders

The formation of thiobarbituric-acid-reactive substances (TBARS) indicative of oxygen-induced lipid peroxidation in vitro was assayed in the frontal cortex, hippocampus, putamen, basal nucleus of Meyn

Abstract: Histochemical and biochemical determinations of total iron, iron (II), and iron (III) contents in brain regions from Parkinson's and Alzheimer's diseases have demonstrated a selective increase of total iron content in parkinsonian substantia nigra zona compacta but not in the zona reticulata. The increase of iron content is mainly in iron (III). The ratio of iron (II):iron (III) in zona compacta changes from almost 2:1 to 1:2. This change is thought to be relevant and may contribute to the selective elevation of basal lipid peroxidation in substantia nigra reported previously. Iron may be available in a free state and thus can participate in autooxidation of dopamine with the resultant generation of H2O2 and oxygen free radicals.

Biochemical substrates and activities of three enzymes were determined in cortical and subcortical brain areas from neuropathologically proven cases with dementia of the Alzheimer type (DAT) and age-m

High performance liquid chromatography with electrochemical detection was used for determining dopamine sulfate in human brain tissues. Dopamine sulfate was examined in the striatum and frontal cortex of human brain. The concentrations of dopamine sulfate in these regions are extremely low in comparison to free dopamine, and to dopamine sulfoconjugates in the cerebrospinal fluid, plasma and urine. Data obtained with this technique in human post mortem brain specimens indicate that the analysis of tissues and body fluids for dopamine conjugates is useful for profiling metabolic dopamine activity in controls and neurodegenerative disorders like Parkinson's disease.