Cocaine-induced sensitization and glutamate plasticity in the nucleus accumbens core : effects of sex

© 2023. The Author(s)..

BACKGROUND: The development and persistence of addiction is mediated in part by drug-induced alterations in nucleus accumbens (NAc) function. AMPA-type glutamate receptors (AMPARs) provide the main source of excitatory drive to the NAc and enhancements in transmission of calcium-permeable AMPARs (CP-AMPARs) mediate increased cue-triggered drug-seeking following prolonged withdrawal. Cocaine treatment regimens that result in psychomotor sensitization enhance subsequent drug-seeking and drug-taking behaviors. Furthermore, cocaine-induced locomotor sensitization followed by 14 days of withdrawal results in an increase in glutamatergic synaptic transmission. However, very few studies have examined cocaine-induced alterations in synaptic transmission of females or potential effects of experimenter-administered cocaine on NAc CP-AMPAR-mediated transmission in either sex.

METHODS: Male and female rats were given repeated systemic cocaine injections to induce psychomotor sensitization (15 mg/kg, i.p. 1 injection/day, 8 days). Controls received repeated saline (1 mL/kg, i.p). After 14-16 days of withdrawal brain slices were prepared and whole-cell patch-clamp approaches in the NAc core were used to measure spontaneous excitatory post-synaptic currents (sEPSC), paired pulse ratio, and CP-AMPAR transmission. Additional female rats from this same cohort were also given a challenge injection of cocaine at withdrawal day 14 to assess the expression of sensitization.

RESULTS: Repeated cocaine produced psychomotor sensitization in both sexes. In males this was accompanied by an increase in sEPSC frequency, but not amplitude, and there was no effect on the paired pulse ratio. Males treated with cocaine and saline had similar sensitivity to Naspm. In contrast, in females there were no significant differences between cocaine and saline groups on any measure, despite females showing robust psychomotor sensitization both during the induction and expression phase.

CONCLUSIONS: Overall, these data reveal striking sex differences in cocaine-induced NAc glutamate plasticity that accompany the induction of psychomotor sensitization. This suggests that the neural adaptations that contribute to sensitization vary by sex.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:14

Enthalten in:

Biology of sex differences - 14(2023), 1 vom: 24. Juni, Seite 41

Sprache:

Englisch

Beteiligte Personen:

Catalfio, Amanda M [VerfasserIn]
Fetterly, Tracy L [VerfasserIn]
Nieto, Allison M [VerfasserIn]
Robinson, Terry E [VerfasserIn]
Ferrario, Carrie R [VerfasserIn]

Links:

Volltext

Themen:

3KX376GY7L
Cocaine
Glutamic Acid
I5Y540LHVR
Journal Article
Receptors, AMPA
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 26.06.2023

Date Revised 03.01.2024

published: Electronic

Citation Status MEDLINE

doi:

10.1186/s13293-023-00525-8

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM358570239