The effect of amphetamine and L-dopa on tetrabenazine-induced suppression of intracranial self-stimulation in the rat.

• The administration of d-amphetamine sulphate resulted in a restoration of intracranial self-stimulation (ICSS) suppressed by tetrabenazine (TBZ). A dose-dependent increase in the rate of ICSS was seen after L-dopa in animals pretreated with TBZ. d-Amhetamine is believed to act by facilitating the nerve-impulse induced release of central catecholamines (CA) whereas the blockage of the granular uptake-storage mechanism by TBZ will prevent the storage of CA formed from the administrated L-dopa and thereby interfere with their release by nerve-impulses. Thus, in the latter case, an activation of central CA receptors in all probability will be due to a dose-dependent diffusion of CA from nerve terminals. It is suggested that the failure to completely antagonize the TBZ-induced suppression of behaviour by L-dopa is due to the fact that a direct activation, independent of the nerve-impulse flow, of central CA receptors easily results in an overstimulation and a reduced specificity in behaviour.

Subject headings

SAMHÄLLSVETENSKAP  -- Psykologi (hsv//swe)

SOCIAL SCIENCES  -- Psychology (hsv//eng)

Keyword

Amphetamine

administration & dosage

pharmacology

Animals

Depression

Chemical

Dose-Response Relationship

Drug

Humans

Injections

Intraperitoneal

Levodopa

administration & dosage

pharmacology

Male

Rats

Self Stimulation

drug effects

Tetrabenazine

pharmacology

Publication and Content Type

ref (subject category)

art (subject category)