Nucleus accumbens lesions reduce amphetamine hyperthermia but not hyperactivity

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Psychopharmacology

Background:

• The nucleus accumbens is a key component of the mesolimbic dopamine system.
• Amphetamine administration causes dose-dependent increases in locomotion and body temperature.

Purpose of the Study:

• To investigate the role of the nucleus accumbens in mediating the behavioral and thermoregulatory effects of amphetamine.
• To determine if dopamine release from the nucleus accumbens is essential for amphetamine-induced hypermotility and hyperthermia.

Main Methods:

• Electrolytic lesions were used to selectively damage the nucleus accumbens in rats.
• Spontaneous locomotion and changes in body temperature were measured after lesioning.
• The effects of d-amphetamine administration on locomotion and body temperature were assessed in lesioned and control rats.

Main Results:

• Electrolytic lesions of the nucleus accumbens resulted in increased spontaneous locomotion.
• These lesions attenuated the hyperthermic response to d-amphetamine.
• However, the hyperkinetic (locomotor) effects of d-amphetamine were not significantly affected by the lesions.

Conclusions:

• Dopamine release within the mesolimbic system, originating from the nucleus accumbens, appears to be involved in amphetamine-induced hyperthermia.
• Other brain structures, in addition to the nucleus accumbens, must play a crucial role in mediating amphetamine-induced hypermotility.