Temporal and dose-dependent differences in simultaneously-induced cocaine hypervigilance and...

Area of Science:

• Neuroscience
• Primatology
• Pharmacology

Background:

• Repeated cocaine exposure can induce hypervigilance and conditioned place preference (CPP) in nonhuman primates (NHPs).
• However, the specific factors influencing these outcomes require further investigation.
• Understanding these factors is crucial for comprehending drug addiction mechanisms.

Purpose of the Study:

• To investigate the time-course and dose-dependency of hypervigilance and CPP in marmosets following cocaine exposure.
• To determine if these behavioral effects persist after a drug-free period.
• To examine the relationship between hypervigilance and CPP, and their correlation with pre- and post-drug behaviors.

Main Methods:

• Marmoset monkeys (Callithrix penicillata) were administered cocaine (3 or 7mg/kg, i.p.).
• Evaluated onset, dose-dependency, and long-term effects of hypervigilance and CPP.
• Assessed correlations with pre-drug behaviors (vigilance, locomotion, exploration) and initial cocaine response.

Main Results:

• Hypervigilance showed a slow onset, was dose-dependent (7mg/kg), lacked long-term effects, and was unrelated to pre-drug behaviors.
• Conditioned place preference (CPP) was rapidly induced (3 and 7mg/kg), exhibited dose-dependent long-term effects, and negatively correlated with pre-drug locomotion and exploration.
• Hypervigilance and CPP were not significantly correlated.

Conclusions:

• Hypervigilance and CPP in marmosets have distinct temporal and dose-dependent profiles.
• These behavioral responses are not always co-expressed in the same individual.
• Pre-drug locomotion and exploration predict the CPP response to low-dose cocaine in NHPs.