Assessment of tolerance to the effects of methamphetamine on daytime and nighttime activity evaluated with actigraphy in rhesus monkeys

Author(s)

Berro, Lais F. ; Andersen, Monica L. ; Howell, Leonard L.

• Document type: Journal article
• Source: Psychopharmacology; v. 234, n. 15, p. 2277-2287, AUG 2017.
• Web of Science Citations: 6

Abstract

Methamphetamine is one of the most largely consumed illicit drugs, and its use is associated with abuse liability and several adverse health effects, such as sleep impairment. Importantly, sleep quality can influence addiction treatment outcomes. Evidence suggests that tolerance can develop to the sleep-disrupting effects of stimulant drugs. The aim of the present study was to investigate the development of tolerance to the actigraphy-based sleep-disrupting and stimulant effects of methamphetamine self-administration in rhesus monkeys. Methamphetamine (0.03 mg/kg/inf, i.v.) self-administration was carried out following three different protocols: 14 consecutive days of self-administration, 5 days/week for 3 weeks, with a 2-day interval between 5-day blocks of self-administration, and 3 days/week for 3 weeks, with a 4-day interval between 3-day blocks of self-administration. Daytime activity and activity-based sleep measures were evaluated with Actiwatch monitors a week before (baseline parameters) and throughout each protocol. Methamphetamine self-administration markedly disrupted sleep-like measures and increased daytime activity. Tolerance developed to those effects with repeated methamphetamine intake exceeding five consecutive days. Inclusion of washout periods (2 or 4 days) between blocks of methamphetamine self-administration attenuated the development of tolerance, with longer breaks from methamphetamine intake being more effective in maintaining the sleep-disrupting and stimulant effects of methamphetamine. Tolerance can develop to the stimulant and sleep-disrupting effects of methamphetamine self-administration. Interruption of drug intake extends the effects of methamphetamine on sleep-like measures and daytime activity. (AU)

• FAPESP's process: 15/25482-3 - Effects of hypnotic drugs on methamphetamine-related behaviors: an ethological and molecular study in rodents and non-human primates
• Grantee: Laís Fernanda Berro
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate