Aging reduces the sensitivity to the reinforcing efficacy of morphine.
Neurobiol Aging
; 97: 28-32, 2021 01.
Article
en En
| MEDLINE
| ID: mdl-33120086
ABSTRACT
The US geriatric population is growing and using more opioids than ever before. The purpose of this study was to determine whether aging influenced the reinforcing efficacy of morphine in male and female rats using a rodent intravenous self-administration paradigm. Male and female aged (20-24 months) and young (2-4 months) Wistar rats were tested at 2 doses of morphine (0.75 mg/kg/infusion and 0.25 mg/kg/infusion). During 10 days of self-administration, aged rats took significantly less morphine than their younger counterparts at the 0.25 mg/kg/infusion dose. Aged males also earned significantly fewer infusions on a progressive ration reinforcement schedule at this dose, suggesting that the reinforcing efficacy of morphine is decreased for this group at this dose. These effects dissipated when a separate group of animals had access to the 0.75 mg/kg/infusion dose for both sexes. Our results indicate that morphine is less reinforcing at lower doses in aged male, but not female rats. This research has potential clinical implications for the chronic treatments involving opioids in aged individuals.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Refuerzo en Psicología
/
Esquema de Refuerzo
/
Envejecimiento
/
Autoadministración
/
Morfina
Tipo de estudio:
Diagnostic_studies
Límite:
Animals
Idioma:
En
Revista:
Neurobiol Aging
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos