Gjermund Henriksen

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Semantic dementia (SD) is a rare clinical syndrome, assigned to the group of frontotemporal lobar degenerations (FTLD). Histopathological analysis has not revealed the deposition of amyloid plaques in the majority of SD cases, in contrast to dementia of the Alzheimer type (AD). However, based on clinical examination alone a reliable differentiation of the(More)
The runner's high describes a euphoric state resulting from long-distance running. The cerebral neurochemical correlates of exercise-induced mood changes have been barely investigated so far. We aimed to unravel the opioidergic mechanisms of the runner's high in the human brain and to identify the relationship to perceived euphoria. We performed a positron(More)
To determine how opiate receptor distribution is co-localized with the distribution of nociceptive areas in the human brain, eleven male healthy volunteers underwent one PET scan with the subtype-nonselective opioidergic radioligand [(18)F]fluoroethyl-diprenorphine under resting conditions. The binding potential (BP), a parameter for the regional cerebral(More)
UNLABELLED The bone-seeking property and the potential exposure of red marrow by the alpha-particle emitter (223)Ra (half-life, 11.43 d) were compared with those of the beta-emitter (89)Sr (half-life, 50.53 d). METHODS The biodistributions of (223)Ra and (89)Sr were studied in mice. Tissue uptake was determined at 1 h, 6 h, 1 d, 3 d, and 14 d after(More)
BACKGROUND A decreased concentration of beta amyloid (1-42) (Abeta42) has consistently been found in the cerebrospinal fluid (CSF) of patients with Alzheimer's disease (AD) and is considered a diagnostic biomarker. However, it is not clear to which extent CSF Abeta42 levels are reflective of cerebral pathology in AD. The aim of the study was to determine(More)
BACKGROUND Pittsburgh Compound B ([¹¹C] PiB) is a specific positron emission tomography (PET) marker of cerebral amyloid deposits. Only few data have been published on in vivo longitudinal changes of amyloid load in Alzheimer's disease (AD) patients, with conflicting results. Therefore, little is known about the factors that influence these changes. (More)
Opioids modulate the affective component of pain and in vivo data indicate that opioids induce activation changes in the rostral ACC, insula and other brain areas. Hence, opioidergic release is to be expected in these brain regions following experimental pain stimulation. We examined healthy volunteers during heat pain and control subjects during rest using(More)
OBJECTIVE To examine the influence of the APOE genotype on levels of beta-amyloid (Abeta) plaque load and atrophy in patients with Alzheimer disease (AD) in vivo. METHODS Thirty-two patients with moderate AD were divided into carriers and noncarriers of the epsilon4 allele. These groups were matched for age, disease duration, education, and cognitive(More)
In vivo functional imaging by means of positron emission tomography (PET) is the sole method for providing a quantitative measurement of mu-, kappa and delta-opioid receptor-mediated signalling in the central nervous system. During the last two decades, measurements of changes to the regional brain opioidergic neuronal activation--mediated by endogenously(More)
In vivo imaging and quantification of amyloid-β plaque (Aβ) burden in small-animal models of Alzheimer's disease (AD) is a valuable tool for translational research such as developing specific imaging markers and monitoring new therapy approaches. Methodological constraints such as image resolution of positron emission tomography (PET) and lack of suitable(More)