Nerve growth factor: effects on D-amphetamine-induced activity and brain monoamines

Area of Science:

• Neuroscience
• Neurobiology
• Pharmacology

Background:

• 6-hydroxydopamine lesions of the nucleus accumbens impair locomotor response to D-amphetamine.
• Nerve growth factor (NGF) plays a role in neuronal survival and function.

Purpose of the Study:

• To investigate the effect of NGF on D-amphetamine-induced locomotor activity in rats with nucleus accumbens lesions.
• To explore whether NGF influences monoamine turnover in the brain.

Main Methods:

• Adult male rats received 6-hydroxydopamine lesions of the nucleus accumbens.
• Injections of saline or NGF were administered near the substantia nigra.
• Locomotor activity response to D-amphetamine was tested 15 days postoperatively.
• Dopamine, norepinephrine, serotonin levels, and turnover rates were analyzed.

Main Results:

• NGF-treated rats exhibited an enhanced locomotor response to D-amphetamine compared to saline-treated controls.
• Catecholamine levels in the striatum and nucleus accumbens were similarly reduced in both groups, suggesting no catecholaminergic regrowth.
• Intracerebral NGF administration enhanced D-amphetamine response in intact rats.
• NGF appeared to increase norepinephrine and serotonin turnover at 3 days postadministration, but not at 15 days.

Conclusions:

• NGF can enhance the behavioral response to D-amphetamine in lesioned rats, independent of catecholaminergic regrowth.
• NGF may modulate brain monoamine turnover, potentially contributing to altered behavioral responses.
• Further research is needed to clarify NGF's precise mechanisms in modulating dopamine turnover.