Specific and non-specific multiple unit activities during pentylenetetrazol seizures. I. Animals with 'encéphale isolé'. 1980

F Velasco, and M Velasco, and R Romo

The present report describes the sequence of activation and deactivation of multiple unit activities (MUA) in the brain stem reticular formation and pyramidal tract, in relation to the clinical seizure and electroencephalographic and electromyographic tonic-clonic discharges induced by pentylenetetrazol (PTZ), in cats immobilized by high spinal transection ('encéphale isolé'). Threshold doses of PTZ (20 mg/kg i.v.) produced the following events: (1) Significant increase in mesencephalic and pontine MUA, anticipating 2 (+/- 1) sec the clinical and electromyographic seizures and 5 (+/- 2) sec the onset of EEG and pyramidal tract tonic-clonic discharges. (2) A further increase in mesencephalic and pontine reticular MUA and electromyogram MUA at the onset of EEG and pyramidal tract tonic-clonic discharges. (3) Significant decrease of EEG spike activity and pyramidal tract MUA to levels below the control period 16 (+/- 8) sec later, while mesencephalic and pontine MUA and electromyogram remained very high. Results suggest that (i) PTZ-induced seizures start in the brain stem reticular formation and propagate to muscles by at least two different pathways: a pyramidal and an extrapyramidal pathway; (ii) that inhibition of seizure activity may start at the cortical level.

UI MeSH Term Description Entries
D008297 Male Males
D009044 Motor Cortex Area of the FRONTAL LOBE concerned with primary motor control located in the dorsal PRECENTRAL GYRUS immediately anterior to the central sulcus. It is comprised of three areas: the primary motor cortex located on the anterior paracentral lobule on the medial surface of the brain; the premotor cortex located anterior to the primary motor cortex; and the supplementary motor area located on the midline surface of the hemisphere anterior to the primary motor cortex. Brodmann Area 4,Brodmann Area 6,Brodmann's Area 4,Brodmann's Area 6,Premotor Cortex and Supplementary Motor Cortex,Premotor and Supplementary Motor Cortices,Anterior Central Gyrus,Gyrus Precentralis,Motor Area,Motor Strip,Precentral Gyrus,Precentral Motor Area,Precentral Motor Cortex,Premotor Area,Premotor Cortex,Primary Motor Area,Primary Motor Cortex,Secondary Motor Areas,Secondary Motor Cortex,Somatic Motor Areas,Somatomotor Areas,Supplementary Motor Area,Area 4, Brodmann,Area 4, Brodmann's,Area 6, Brodmann,Area 6, Brodmann's,Area, Motor,Area, Precentral Motor,Area, Premotor,Area, Primary Motor,Area, Secondary Motor,Area, Somatic Motor,Area, Somatomotor,Area, Supplementary Motor,Brodmann's Area 6s,Brodmanns Area 4,Brodmanns Area 6,Central Gyrus, Anterior,Cortex, Motor,Cortex, Precentral Motor,Cortex, Premotor,Cortex, Primary Motor,Cortex, Secondary Motor,Cortices, Secondary Motor,Gyrus, Anterior Central,Gyrus, Precentral,Motor Area, Precentral,Motor Area, Primary,Motor Area, Secondary,Motor Area, Somatic,Motor Areas,Motor Cortex, Precentral,Motor Cortex, Primary,Motor Cortex, Secondary,Motor Strips,Precentral Motor Areas,Precentral Motor Cortices,Premotor Areas,Primary Motor Areas,Primary Motor Cortices,Secondary Motor Area,Secondary Motor Cortices,Somatic Motor Area,Somatomotor Area,Supplementary Motor Areas
D010433 Pentylenetetrazole A pharmaceutical agent that displays activity as a central nervous system and respiratory stimulant. It is considered a non-competitive GAMMA-AMINOBUTYRIC ACID antagonist. Pentylenetetrazole has been used experimentally to study seizure phenomenon and to identify pharmaceuticals that may control seizure susceptibility. Leptazole,Pentamethylenetetrazole,Pentetrazole,Cardiazol,Corasol,Corazol,Corazole,Korazol,Korazole,Metrazol,Metrazole,Pentazol,Pentylenetetrazol
D011712 Pyramidal Tracts Fibers that arise from cells within the cerebral cortex, pass through the medullary pyramid, and descend in the spinal cord. Many authorities say the pyramidal tracts include both the corticospinal and corticobulbar tracts. Corticobulbar Tracts,Corticospinal Tracts,Decussation, Pyramidal,Corticobulbar Tract,Corticospinal Tract,Pyramidal Decussation,Pyramidal Tract,Tract, Corticobulbar,Tract, Corticospinal,Tract, Pyramidal,Tracts, Corticobulbar,Tracts, Corticospinal,Tracts, Pyramidal
D012154 Reticular Formation A region extending from the PONS & MEDULLA OBLONGATA through the MESENCEPHALON, characterized by a diversity of neurons of various sizes and shapes, arranged in different aggregations and enmeshed in a complicated fiber network. Formation, Reticular,Formations, Reticular,Reticular Formations
D002415 Cats The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801) Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D003655 Decerebrate State A condition characterized by abnormal posturing of the limbs that is associated with injury to the brainstem. This may occur as a clinical manifestation or induced experimentally in animals. The extensor reflexes are exaggerated leading to rigid extension of the limbs accompanied by hyperreflexia and opisthotonus. This condition is usually caused by lesions which occur in the region of the brainstem that lies between the red nuclei and the vestibular nuclei. In contrast, decorticate rigidity is characterized by flexion of the elbows and wrists with extension of the legs and feet. The causative lesion for this condition is located above the red nuclei and usually consists of diffuse cerebral damage. (From Adams et al., Principles of Neurology, 6th ed, p358) Decerebrate Posturing,Decorticate Rigidity,Decorticate State,Rigidity, Decerebrate,Rigidity, Decorticate,Decerebrate Posturings,Decerebrate Rigidity,Decerebrate States,Decorticate Rigidities,Decorticate States,Posturing, Decerebrate,Posturings, Decerebrate,Rigidities, Decorticate,State, Decerebrate,States, Decerebrate
D004569 Electroencephalography Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain. EEG,Electroencephalogram,Electroencephalograms
D004576 Electromyography Recording of the changes in electric potential of muscle by means of surface or needle electrodes. Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D000200 Action Potentials Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli. Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential

Related Publications

F Velasco, and M Velasco, and R Romo
January 1979, Journal de physiologie,
F Velasco, and M Velasco, and R Romo
April 1976, Archives internationales de physiologie et de biochimie,
F Velasco, and M Velasco, and R Romo
November 1971, Brain research,
F Velasco, and M Velasco, and R Romo
January 1978, Acta neurologica,
F Velasco, and M Velasco, and R Romo
March 1980, Electroencephalography and clinical neurophysiology,
F Velasco, and M Velasco, and R Romo
October 1954, Geriatrics,
Copied contents to your clipboard!