Perinatal exposure to delta(9)-tetrahydrocannabinol alters heroin-induced place conditioning and fos-immunoreactivity.

In the present study, the effects of perinatal exposure to Delta(9)-tetrahydrocannabinol (THC) on heroin-induced place conditioning and Fos-immunoreactivity (Fos-IR) were examined. Male albino Wistar rats (N=104) were pretreated with vehicle (n=52) or 5 mg/kg THC (n=52) from postnatal days 4 through 14. At approximately 8 weeks of age, 72 rats were divided into six equal groups (n=12 per group) and injected subcutaneously (s.

Chronic cannabinoid exposure produces lasting memory impairment and increased anxiety in adolescent but not adult rats.

Although many studies have examined the acute behavioural effects of cannabinoids in rodents, few have examined the lasting effects of cannabinoids at different developmental ages. This study compared lasting effects of cannabinoid exposure occurring in adolescence to that occurring in early adulthood. Forty, 30-day old (adolescent) and 18, 56-day old (adult) female albino Wistar rats were injected with vehicle or incremental doses of the cannabinoid receptor agonist (-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hydroxypropyl) cyclohexanol (CP 55,940) once per day for 21 consecutive days (150, 200 and 300 microg/kg i.

The cannabinoid receptor antagonist SR 141716 attenuates overfeeding induced by systemic or intracranial morphine.

Rationale: Considerable interplay exists between the brain's opioid and cannabinoid systems. These systems are both involved in the control of appetite and research supports the notion that the opioid system modulates the role of the cannabinoid system on appetite. However, the ability of the cannabinoid system to modulate the opioid system's control over appetite has not been well studied.