Biomaterial Database

Glutamate antagonists in the reticular formation reduce the acoustic startle response. 1993

W Krase, and M Koch, and H U Schnitzler

Tierphysiologie, Universität Tübingen, Germany.

A previous study has shown that the acoustic responsiveness of reticulospinal neurones in the caudal pontine reticular nucleus (PnC) is reduced by glutamate antagonists. It was postulated that the acoustic startle response is mediated by glutamate receptors on PnC-neurones. In the present study, we tested this hypothesis by local microinjections of different glutamate antagonists into the PnC of unrestrained awake rats. In order to differentiate the drug effects on the head and body startle responses, we measured the head startle response electromyographically, and the body startle response in a ballistic chamber. Both the AMPA/kainate and the NMDA receptor antagonists reduced both components of the startle response dose-dependently. We conclude that both subtypes of ionotropic glutamate receptors in the PnC are relevant for the acoustic startle response in rats.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008845	Microinjections	The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.	Microinjection
D011149	Pons	The front part of the hindbrain (RHOMBENCEPHALON) that lies between the MEDULLA and the midbrain (MESENCEPHALON) ventral to the cerebellum. It is composed of two parts, the dorsal and the ventral. The pons serves as a relay station for neural pathways between the CEREBELLUM to the CEREBRUM.	Pons Varolii,Ponte,Pons Varolius,Pontes,Varolii, Pons,Varolius, Pons
D011810	Quinoxalines		Quinoxaline
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
D003864	Depression, Chemical	The decrease in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.	Chemical Depression,Chemical Depressions,Depressions, Chemical
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
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
D013216	Reflex, Startle	A complex involuntary response to an unexpected strong stimulus. The reaction involves physical movement away from the stimulus, MUSCLE CONTRACTION and limb flexion, BLINKING, and changes in HEART RATE, BLOOD PRESSURE, and RESPIRATION.	Startle Reaction,Acoustic Startle Reflex,Reflex, Moro,Startle Response,Moro Reflex,Reaction, Startle,Reactions, Startle,Reflex, Acoustic Startle,Response, Startle,Responses, Startle,Startle Reactions,Startle Reflex,Startle Reflex, Acoustic,Startle Responses