Biomaterial Database

The reduced responsiveness of neurones in nucleus reticularis gigantocellularis following their excitation by peripheral nerve stimulation. 1976

J E Fox, and J H Wolstencroft

1. Post-stimulus histograms of neuronal activity, constructed from extracellular recordings in decerebrate, decerebellate cats, have been used to investigate the responsiveness of neurons in nucleus reticularis gigantocellularis following their excitation by a peripheral nerve stimulus. 2. The response to a testing stimulus applied to a peripheral nerve was depressed following the response to a conditioning stimulus applied to the same or a different peripheral nerve. This reduction in responsiveness was maximal within 50 msec of the peak of the response to the conditioning stimulus. Response latencies to the testing stimulus were increased during the period of reduced responsiveness. 3. Responsiveness to a peripheral nerve stimulus was also reduced following a spontaneous or an antidromically evoked spike, but this effect was weaker and much shorter-lasting than that following a nerve-evoked spike. Thus, the reduced responsiveness cannot be solely due to phenomena which are an inevitable consequence of an action potential in the neurone. 4. In spontaneously firing neurones, the duration of the reduced responsiveness to a testing stimulus generally outlasted the depression of spontaneous activity which often followed an excitation evoked by a peripheral nerve conditioning stimulus. 5. The reduction in responsiveness to a testing stimulus applied to the same nerve as the conditioning stimulus was greater and longer-lasting than that to a testing stimulus applied to a different nerve. 6. When stimuli were applied to one nerve at a relatively high rate, the neurone became much less responsive to that input, but simultaneously became more responsive to low rate stimulation of other nerves. 7. It is concluded that the greater part of the reduced responsiveness is due to events occurring on the input pathway to a reticular neurone, or possibly in the region of the afferent endings on its dendrites. These processes may allow selective changes in responsiveness to different inputs, and enable the units to act as novelty detectors.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009431	Neural Conduction	The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.	Nerve Conduction,Conduction, Nerve,Conduction, Neural,Conductions, Nerve,Conductions, Neural,Nerve Conductions,Neural Conductions
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D010525	Peripheral Nerves	The nerves outside of the brain and spinal cord, including the autonomic, cranial, and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons. The connective tissue layers include, from the outside to the inside, the epineurium, the perineurium, and the endoneurium.	Endoneurium,Epineurium,Perineurium,Endoneuriums,Epineuriums,Nerve, Peripheral,Nerves, Peripheral,Perineuriums,Peripheral Nerve
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
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D005260	Female		Females
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