Biomaterial Database

Tectal and tegmental excitation in dorsal neck motoneurones of the cat. 1992

B Alstermark, and M J Pinter, and S Sasaki

Department of Physiology, University of Göteborg, Sweden.

1. Intracellular recordings were made from 116 splenius (SPL) and 103 biventer cervicis and complexus (BCC) alpha-motoneurones in nineteen cats anaesthetized with alpha-chloralose. 2. Electrical stimulation in the contralateral tectum evoked disynaptic excitatory postsynaptic potentials (EPSPs) in the motoneurones when a train of stimuli was applied in the ventral layers throughout the superior colliculus. In the rostral half of the superior colliculus, these EPSPs were due to stimulation of ascending collaterals of tectofugal neurones. EPSPs of a presumed trisynaptic linkage could only be evoked from the dorsal and intermediate tectal layers in the caudal half of the superior colliculus. It is concluded that the tectofugal neurones which evoked the disynaptic EPSPs are mainly located in the caudal half of the superior colliculus. 3. Disynaptic EPSPs were evoked in the motoneurones by a train of stimuli in the contralateral fields of Forel and Zona incerta, which were due to stimulation of ascending collaterals from the tectofugal neurones. 4. Spatial facilitation experiments revealed that tectal disynaptic EPSPs in the neck motoneurones were mediated via reticulospinal neurones with convergent input from cortico-reticular neurones. 5. A train of stimuli in the ipsilateral tectum evoked EPSPs with latencies compatible with a trisynaptic linkage, while disynaptic EPSPs at low threshold could be elicited from the underlying tegmentum. Similar disynaptic EPSPs could be evoked from the ipsilateral fields of Forel. It is suggested that some of the disynaptic tegmental EPSPs in SPL and BCC motoneurones can be mediated via a tegmento-reticulospinal pathway which originates in the cuneiform nucleus.

UI	MeSH Term	Description	Entries
D007839	Functional Laterality	Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.	Ambidexterity,Behavioral Laterality,Handedness,Laterality of Motor Control,Mirror Writing,Laterality, Behavioral,Laterality, Functional,Mirror Writings,Motor Control Laterality,Writing, Mirror,Writings, Mirror
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D009333	Neck	The part of a human or animal body connecting the HEAD to the rest of the body.	Necks
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
D003336	Tectum Mesencephali	The dorsal portion or roof of the midbrain which is composed of two pairs of bumps, the INFERIOR COLLICULI and the SUPERIOR COLLICULI. These four colliculi are also called the quadrigeminal bodies (TECTUM MESENCEPHALI). They are centers for sensorimotor integration.	Corpora Quadrigemina,Lamina Quadrigemina,Quadrigeminal Plate,Tectal Plate,Commissure of Inferior Colliculus,Commissure of Superior Colliculus,Colliculus Commissure, Inferior,Colliculus Commissure, Superior,Inferior Colliculus Commissure,Inferior Colliculus Commissures,Mesencephalus, Tectum,Plate, Quadrigeminal,Plate, Tectal,Quadrigeminal Plates,Superior Colliculus Commissure,Superior Colliculus Commissures,Tectal Plates,Tectum Mesencephalus
D004027	Diencephalon	The paired caudal parts of the PROSENCEPHALON from which the THALAMUS; HYPOTHALAMUS; EPITHALAMUS; and SUBTHALAMUS are derived.	Interbrain,Interbrains
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
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
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
D013127	Spinal Nerves	The 31 paired peripheral nerves formed by the union of the dorsal and ventral spinal roots from each spinal cord segment. The spinal nerve plexuses and the spinal roots are also included.	Nerve, Spinal,Nerves, Spinal,Spinal Nerve