Biomaterial Database

The effects of acute cocaine administration on auditory event-related potentials in rats. 1993

P Robledo, and W M Kaneko, and C L Ehlers

Scripps Research Institute, Department of Neuropharmacology, La Jolla, CA 92037.

Cocaine administration has been shown to affect several sites in the limbic forebrain. The nucleus accumbens has been implicated as an important site for the reinforcing aspects of this drug whereas, the amygdala and hippocampus may be more involved in drug conditioning and/or drug induced changes in the perception of stimuli. In the present study, auditory event-related potentials (ERPs) were utilized to explore the effects of cocaine on sensory processing in several limbic sites. Eleven adult male Wistar rats were stereotaxically implanted with electrodes aimed at the dentate gyrus, dorsal hippocampus (CA1-CA2), amygdala, and nucleus accumbens. The rats received intraperitoneal injections of either saline, 2.5, 5.0, 10.0 or 20 mg/kg of cocaine. The ERPs were recorded in response to an auditory 'oddball' paradigm consisting of frequently and infrequently presented tones. Cocaine was found to produce a dose dependent decrease in the variance of the amplitude of several ERP components in the amygdala and the hippocampal formation but not in the nucleus accumbens. Cocaine also produced a decrease in the latency of the N1 component in the amygdala. No significant changes were observed in the amplitude of the ERP components following any of the cocaine doses studied, suggesting that cocaine may not increase the salience of auditory stimuli in these structures. The observed reduction in the variance of the ERPs may suggest an increased focussing of the animals' attention to the auditory stimuli. These studies also suggest that the sensory/cognitive aspects involved in cocaine's actions, as quantified by ERPs, may primarily involve the hippocampal formation and the amygdala, but not the nucleus accumbens.

UI	MeSH Term	Description	Entries
D008032	Limbic System	A set of forebrain structures common to all mammals that is defined functionally and anatomically. It is implicated in the higher integration of visceral, olfactory, and somatic information as well as homeostatic responses including fundamental survival behaviors (feeding, mating, emotion). For most authors, it includes the AMYGDALA; EPITHALAMUS; GYRUS CINGULI; hippocampal formation (see HIPPOCAMPUS); HYPOTHALAMUS; PARAHIPPOCAMPAL GYRUS; SEPTAL NUCLEI; anterior nuclear group of thalamus, and portions of the basal ganglia. (Parent, Carpenter's Human Neuroanatomy, 9th ed, p744; NeuroNames, http://rprcsgi.rprc.washington.edu/neuronames/index.html (September 2, 1998)).	Limbic Systems,System, Limbic,Systems, Limbic
D008297	Male		Males
D003042	Cocaine	An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake.	Cocaine HCl,Cocaine Hydrochloride,HCl, Cocaine,Hydrochloride, Cocaine
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004567	Electrodes, Implanted	Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.	Implantable Electrodes,Implantable Stimulation Electrodes,Implanted Electrodes,Implanted Stimulation Electrodes,Electrode, Implantable,Electrode, Implantable Stimulation,Electrode, Implanted,Electrode, Implanted Stimulation,Electrodes, Implantable,Electrodes, Implantable Stimulation,Electrodes, Implanted Stimulation,Implantable Electrode,Implantable Stimulation Electrode,Implanted Electrode,Implanted Stimulation Electrode,Stimulation Electrode, Implantable,Stimulation Electrode, Implanted,Stimulation Electrodes, Implantable,Stimulation Electrodes, Implanted
D005072	Evoked Potentials, Auditory	The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.	Auditory Evoked Potentials,Auditory Evoked Response,Auditory Evoked Potential,Auditory Evoked Responses,Evoked Potential, Auditory,Evoked Response, Auditory,Evoked Responses, Auditory,Potentials, Auditory Evoked
D000161	Acoustic Stimulation	Use of sound to elicit a response in the nervous system.	Auditory Stimulation,Stimulation, Acoustic,Stimulation, Auditory
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013238	Stereotaxic Techniques	Techniques used mostly during brain surgery which use a system of three-dimensional coordinates to locate the site to be operated on.	Stereotactic Techniques,Stereotaxic Technics,Stereotactic Technique,Stereotaxic Technic,Stereotaxic Technique,Technic, Stereotaxic,Technics, Stereotaxic,Technique, Stereotactic,Technique, Stereotaxic,Techniques, Stereotactic,Techniques, Stereotaxic
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats