Biomaterial Database

Hippocampal rhythmical slow activity following ibotenic acid lesions of the septal region. I. Relations to behavior and effects of atropine and urethane. 1987

D J Stewart, and C H Vanderwolf

Department of Psychology, University of Western Ontario, London, Canada.

The effects of intraseptal injections of various concentrations of ibotenic acid on hippocampal electrical activity were studied in freely moving and urethane-anesthetized rats. Ibotenic acid selectively abolished the atropine-sensitive form of hippocampal rhythmical slow activity (RSA) normally seen during urethane anesthesia. Large amplitude irregular activity (LIA) and RSA in the waking state were somewhat depressed as well. Despite this, clear RSA persisted in the waking state in association with locomotion or struggling (Type 1 behavior). As in normal rats, such RSA was resistant to systemic administration of atropine. Analysis of brain sections stained with gallocyanin or for acetylcholinesterase showed that ibotenic acid produced cell loss in the dorsal lateral septal nucleus and the septohippocampal nucleus. Cells in the medial septal and diagonal band nuclei were resistant to ibotenic acid. The results suggest that intrinsic septal circuitry is critically involved in the generation of the atropine-sensitive (presumably cholinergic) form of RSA. The mechanisms by which LIA and the two forms of RSA are generated in the hippocampus is discussed.

UI	MeSH Term	Description	Entries
D007051	Ibotenic Acid	A neurotoxic isoxazole (similar to KAINIC ACID and MUSCIMOL) found in AMANITA mushrooms. It causes motor depression, ataxia, and changes in mood, perceptions and feelings, and is a potent excitatory amino acid agonist.	Acid, Ibotenic
D008297	Male		Males
D009043	Motor Activity	Body movements of a human or an animal as a behavioral phenomenon.	Activities, Motor,Activity, Motor,Motor Activities
D010080	Oxazoles	Five-membered heterocyclic ring structures containing an oxygen in the 1-position and a nitrogen in the 3-position, in distinction from ISOXAZOLES where they are at the 1,2 positions.	Oxazole,1,3-Oxazolium-5-Oxides,Munchnones,1,3 Oxazolium 5 Oxides
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D004553	Electric Conductivity	The ability of a substrate to allow the passage of ELECTRONS.	Electrical Conductivity,Conductivity, Electric,Conductivity, Electrical
D006624	Hippocampus	A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.	Ammon Horn,Cornu Ammonis,Hippocampal Formation,Subiculum,Ammon's Horn,Hippocampus Proper,Ammons Horn,Formation, Hippocampal,Formations, Hippocampal,Hippocampal Formations,Hippocampus Propers,Horn, Ammon,Horn, Ammon's,Proper, Hippocampus,Propers, Hippocampus,Subiculums
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
D001285	Atropine	An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.	AtroPen,Atropin Augenöl,Atropine Sulfate,Atropine Sulfate Anhydrous,Atropinol,Anhydrous, Atropine Sulfate,Augenöl, Atropin,Sulfate Anhydrous, Atropine,Sulfate, Atropine
D014520	Urethane	Antineoplastic agent that is also used as a veterinary anesthetic. It has also been used as an intermediate in organic synthesis. Urethane is suspected to be a carcinogen.	Ethyl Carbamate,Urethan,Carbamate, Ethyl