Numerical density of mu opioidreceptor expressing neurons in the frontal cortex of drug related fatalities

Citation
P. Schmidt et al., Numerical density of mu opioidreceptor expressing neurons in the frontal cortex of drug related fatalities, FOREN SCI I, 115(3), 2001, pp. 219-229
Citations number
35
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Research/Laboratory Medicine & Medical Tecnology
Journal title
FORENSIC SCIENCE INTERNATIONAL
ISSN journal
0379-0738 → ACNP
Volume
115
Issue
3
Year of publication
2001
Pages
219 - 229
Database
ISI
SICI code
0379-0738(20010115)115:3<219:NDOMOE>2.0.ZU;2-M
Abstract
In animal and cell culture experiments, chronic morphine treatment has been followed by 'up'- as well as 'down-regulation' of the mu opioidreceptor (m u OR) number. The present postmortem morphometric study of morphine-related fatalities of drug addicts (n = 12 and 22-35 years old, with blood unconju gated morphine levels from 27.1 to 458 ng/ml, m.v. 198.5 ng/ml) versus a no n-addicted control group (n = 13 and 10-44 years old) was intended to exami ne whether chronic opiate exposure affects the numerical density of mu OR e xpressing neurons in the human neocortex (area 10 according to Brodmann). F or the immunohistochemical procedure, thick (100 mum) vibratome sections we re incubated with a monoclonal antibody against the mu OR [Arvidsson et al. , J. Neurosci. 15 (1995) 3328] and immunoreactive sites were visualized usi ng an immunoperoxidase protocol. The numerical densities of mu OR-expressin g and Nissl-stained neurons were assessed morphometrically (camera lucida-d rawings). In both collectives, the anti-mu OR immunoreactivity was mainly f ound in pyramidal neurons of layers (L) II/III and V and in multiform neuro ns of L VI. In the drug-related fatalities and the control group, the densi ty of neurons expressing mu OR protein was similar, amounting for 2698 +/- 153 and 2688 +/- 172/mm(3), respectively. These findings extend the binding studies of opioid ligands in postmortem brains of heroin addicts [Gabilond o ct al., Psychopharmacology 115 (1994) 135] revealing similar receptor den sities and affinities by showing no difference in the density of mu OR-posi tive neurons. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.