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Lars Oreland

Bio: Lars Oreland is an academic researcher from Uppsala University. The author has contributed to research in topics: Monoamine oxidase & Monoamine neurotransmitter. The author has an hindex of 66, co-authored 380 publications receiving 15621 citations. Previous affiliations of Lars Oreland include University of Tartu & National Board of Health and Welfare.


Papers
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Journal ArticleDOI
TL;DR: The functional linkage between platelet MAO activity and psychopathology was explored by analyzing temperamental correlates in 40 male subjects by means of scales from the Eysenck Personality Questionnaire, the Zuckerman Sensation Seeking Inventory, and the Karolinska Scales of Personality.
Abstract: The functional linkage between platelet MAO activity and psychopathology was explored by analyzing temperamental correlates in 40 male subjects by means of scales from the Eysenck Personality Questionnaire (EPQ), the Zuckerman Sensation Seeking Inventory, and the Karolinska Scales of Personality (KSP). Linear correlations were found with two sensation seeking scales, replicating earlier findings. However, nonlinear correlations predominated. Subjects with intermediate platelet MAO activity had higher scores in conformity scales and lower scores in anxiety and hostility scales than low and high MAO subgroups. Low MAO subjects showed a pattern of higher scores in KSP Impulsiveness, EPQ Neuroticism, and KSP Somatic Anxiety and Irritability and lower scores in KSP Socialization, in line with personality profiles found in alcoholics, psychopaths, and suicide attempters who also tend to have low platelet MAO activity. High MAO subjects scored lower in sensation seeking and conformity scales and higher in KSP Psychasthenia, Muscular Tension and Suspicion scales, consistent with clinical links between high platelet MAO activity and anxiety and paranoia.

459 citations

Journal ArticleDOI
23 Jan 1987-Science
TL;DR: Suicide enzyme inactivators labeled with positron emitters can be used to quantitate the distribution and kinetic characteristics of MAO in human brain structures and show rapid clearance of the inactive enantiomer and retention of the active enantiomers within MAO B-rich brain structures.
Abstract: The regional distributions of monoamine oxidase (MAO) types A and B have been identified in human brain in vivo with intravenously injected 11C-labeled suicide enzyme inactivators, clorgyline and L-deprenyl, and positron emission tomography. The rapid brain uptake and retention of radioactivity for both 11C tracers indicated irreversible trapping. The anatomical distribution of 11C paralleled the distribution of MAO A and MAO B in human brain in autopsy material. The corpus striatum, thalamus, and brainstem contained high MAO activity. The magnitudes of uptake of both [11C]clorgyline and L-[11C]deprenyl were markedly reduced in one subject treated with the antidepressant MAO inhibitor phenelzine. A comparison of the brain uptake and retention of the 11C-labeled inactive (D-) and active (L-) enantiomers of deprenyl showed rapid clearance of the inactive enantiomer and retention of the active enantiomer within MAO B-rich brain structures, in agreement with the known stereoselectivity of MAO B for L-deprenyl. Prior treatment with unlabeled L-deprenyl prevented retention of L-[11C]deprenyl. Thus, suicide enzyme inactivators labeled with positron emitters can be used to quantitate the distribution and kinetic characteristics of MAO in human brain structures.

372 citations

Journal ArticleDOI
TL;DR: Cross-correlation studies of the data indicated that the activities of the two enzyme forms are under some form of organized control across the whole brain, consistent with a genetic regulation of the enzyme forms.
Abstract: The effect of age upon monoamine oxidase -A and -B (MAO-A and -B) in 23 different regions of human brain was determined. There was a significant positive correlation with age in 19 out of 23 regions for MAO-B, but no positive correlation with age was found for MAO-A. The increased MAO-B activity was found, in 5 out of 5 regions tested, to be due entirely to an increased enzyme concentration, rather than due to an increased molecular turnover number of the enzyme. The responses of the mitochondrial marker enzymes succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) were studied in 5 brain regions, and no consistent change in activity found with age. The lysosomal enzyme acid phosphatase was found to tend towards an increased activity with age. No difference in either the specific activities or molecular characteristics of MAO were found between men and women. Cross-correlation studies of the data, after compensation for the effects of age, indicated that the activities of the two enzyme forms are under some form of organized control across the whole brain. Such a finding is consistent with a genetic regulation of the enzyme forms.

326 citations

Journal ArticleDOI
TL;DR: In postmortem investigations of patients with dementia of Alzheimer type (AD/SDAT) the brain weight was significantly reduced when compared to controls and the activity of monoamine oxidase B was increased suggesting a proliferation of extra neuronal tissue in the AD/ SDAT-brains.

295 citations

Journal ArticleDOI
TL;DR: Both 5HIAA and HVA were positively and significantly correlated to platelet MAO activity in the healthy subjects, but not in any of the patient groups.
Abstract: Platelet monoamine oxidase (MAO) activity and cerebrospinal fluid (CSF) concentrations of 5-hydroxyindoleacetic acid (5HIAA), homovanillic acid (HVA), and 4-hydroxy-3-methoxyphenylglycol (HMPG) were simultaneously measured in 20 currently depressed patients, 11 recovered depressed patients, 15 nondepressed suicide attempters, and 42 healthy control subjects. Both 5HIAA and HVA were positively and significantly correlated to platelet MAO activity in the healthy subjects, but not in any of the patient groups. Suicide attempters had significantly lower CSF 5HIAA than nonsuicidal patients.

279 citations


Cited by
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Journal ArticleDOI
19 Oct 2006-Nature
TL;DR: Treatments targeting basic mitochondrial processes, such as energy metabolism or free-radical generation, or specific interactions of disease-related proteins with mitochondria hold great promise in ageing-related neurodegenerative diseases.
Abstract: Many lines of evidence suggest that mitochondria have a central role in ageing-related neurodegenerative diseases. Mitochondria are critical regulators of cell death, a key feature of neurodegeneration. Mutations in mitochondrial DNA and oxidative stress both contribute to ageing, which is the greatest risk factor for neurodegenerative diseases. In all major examples of these diseases there is strong evidence that mitochondrial dysfunction occurs early and acts causally in disease pathogenesis. Moreover, an impressive number of disease-specific proteins interact with mitochondria. Thus, therapies targeting basic mitochondrial processes, such as energy metabolism or free-radical generation, or specific interactions of disease-related proteins with mitochondria, hold great promise.

5,368 citations

Journal ArticleDOI
TL;DR: The authors suggest that the most promising route to effective strategies for the prevention of adolescent alcohol and other drug problems is through a risk-focused approach.
Abstract: The authors suggest that the most promising route to effective strategies for the prevention of adolescent alcohol and other drug problems is through a risk-focused approach. This approach requires the identification of risk factors for drug abuse, identification of methods by which risk factors have been effectively addressed, and application of these methods to appropriate high-risk and general population samples in controlled studies. The authors review risk and protective factors for drug abuse, assess a number of approaches for drug abuse prevention potential with high-risk groups, and make recommendations for research and practice.

5,348 citations

Journal ArticleDOI
TL;DR: For example, this article found that exposure to multiple types and repeated episodes of maltreatment is associated with increased risks of severe maltreatment and psychological consequences, which has longlasting effects on mental health, drug and alcohol misuse (especially in girls), risky sexual behaviour, obesity, and criminal behaviour.

3,034 citations

Journal ArticleDOI
11 Mar 1983-Science
TL;DR: Advances in neurotransmitter systems involved in the symptomatic manifestations of neurological and psychiatric disorders reflect a close interaction between experimental and clinical neuroscientists in which information derived from basic neurobiology is rapidly utilized to analyze disorders of the human brain.
Abstract: Great emphasis is being placed on identification of neurotransmitter systems involved in the symptomatic manifestations of neurological and psychiatric disorders. In the case of Alzheimer's disease, which now seems to be one of the most common causes of mental deterioration in the elderly, compelling evidence has been developed that acetylcholine-releasing neurons, whose cell bodies lie in the basal forebrain, selectively degenerate. These cholinergic neurons provide widespread innervation of the cerebral cortex and related structures and appear to play an important role in cognitive functions, especially memory. These advances reflect a close interaction between experimental and clinical neuroscientists in which information derived from basic neurobiology is rapidly utilized to analyze disorders of the human brain.

2,995 citations