Abstract
Sprague-Dawley rats were subjected to a moderate level (2.2 atm) of traumatic brain injury (TBI) using fluid percussion. Injured animals were allowed to survive posttrauma for periods of 5 min, 3 h, and 24 h. The effect of TBI on binding to forebrain opiate receptors was assessed using quantitative receptor autoradiography, and compared to a sham control group. Binding of [3H]DAGO to mu receptors in neocortex and the CA1 pyramidal layer of the hippocampus was significantly decreased in the 24-h group (p<0.05). [3H]Bremazocine binding to kappa receptors was unchanged at 5 min and 24 h, but showed large decreases 3 h after TBI in the CA1 pyramidal layer (65%, p<0.05) and dentate gyrus (43%, p<0.05). Levels of delta binding (measured with [3H]DSLET) and lambda binding (measured with [3H]naloxone) were unaffected by TBI. These data support previous suggestions of a role for endogenous opioids in TBI, and provide further evidence that mu and kappa opioid receptor subtypes in neocortex and hippocampus may have different functions in TBI.
Original language | English (US) |
---|---|
Pages (from-to) | 95-107 |
Number of pages | 13 |
Journal | Molecular and Chemical Neuropathology |
Volume | 16 |
Issue number | 1-2 |
DOIs | |
State | Published - Feb 1992 |
Externally published | Yes |
Keywords
- dentate gyrus
- endogenous opioids
- excitotoxicity
- hippocampus
- kappa opiate receptors
- mu opiate receptors
- Traumatic brain injury
ASJC Scopus subject areas
- Neuroscience(all)
- Clinical Neurology
- Molecular Biology