Biomaterial Database

Convergence properties of solitary tract neurones driven synaptically by cardiac vagal afferents in the mouse. 1998

J F Paton

Department of Physiology, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, UK. julian.f.r.paton@bris.ac.uk

1. Cardiac vagal receptors are chemically and/or mechanically sensitive but it is unknown if this information is preserved centrally within the nucleus of the solitary tract (NTS). The present study had two aims: first, to investigate qualitatively whether both mechanically and chemically sensitive cardiac vagal encoding were preserved within the NTS, and second, to determine the patterns of convergence from other cardiorespiratory afferents to NTS neurones receiving cardiac vagal inputs. 2. The extracellular activity of single NTS neurones was investigated during stimulation of both chemically and mechanically sensitive cardiac vagal receptors in a working heart-brainstem preparation of mouse. Chemically sensitive cardiac receptors were stimulated using intra-left ventricular injections of either veratridine (1-3 microg kg-1), bradykinin (0.25-1 microg) or prostaglandin E2 (100-200 ng), whereas the left ventricle was distended to activate cardiac mechanoreceptors. 3. Forty-three NTS neurones were activated both synaptically by electrical stimulation of the ipsilateral vagus nerve (latency, 35 +/- 3 ms), and by intra-left ventricular injection of veratridine and also, in some cases, by bradykinin and/or PGE2. These NTS neurones were delineated into two populations based on their response to left ventricular distension and convergence properties. Left ventricular distension-insensitive neurones (n = 30) were excited by stimulation of carotid body chemoreceptors (81 %) but not arterial baroreceptors (3 %; i.e. n = 1 neurone), whereas distension-sensitive cells (n = 13) were activated mainly by baroreceptors (86 %) rather than peripheral chemoreceptors (14 %; i.e. n = 1 neurone). 4. The data reveal two distinct populations of NTS neurones receiving cardiac vagal inputs: (a) cells responsive to veratridine stimulation only, and (b) neurones activated by both veratridine and mechanical stimuli. The specific convergence pattern of baroreceptors and chemoreceptors to these cardioreceptive NTS neurones is discussed in relation to a common afferent modality integration within the NTS.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008465	Mechanoreceptors	Cells specialized to transduce mechanical stimuli and relay that information centrally in the nervous system. Mechanoreceptor cells include the INNER EAR hair cells, which mediate hearing and balance, and the various somatosensory receptors, often with non-neural accessory structures.	Golgi Tendon Organ,Golgi Tendon Organs,Krause's End Bulb,Krause's End Bulbs,Mechanoreceptor,Mechanoreceptor Cell,Meissner's Corpuscle,Neurotendinous Spindle,Neurotendinous Spindles,Receptors, Stretch,Ruffini's Corpuscle,Ruffini's Corpuscles,Stretch Receptor,Stretch Receptors,Mechanoreceptor Cells,Bulb, Krause's End,Bulbs, Krause's End,Cell, Mechanoreceptor,Cells, Mechanoreceptor,Corpuscle, Meissner's,Corpuscle, Ruffini's,Corpuscles, Ruffini's,End Bulb, Krause's,End Bulbs, Krause's,Krause End Bulb,Krause End Bulbs,Krauses End Bulb,Krauses End Bulbs,Meissner Corpuscle,Meissners Corpuscle,Organ, Golgi Tendon,Organs, Golgi Tendon,Receptor, Stretch,Ruffini Corpuscle,Ruffini Corpuscles,Ruffinis Corpuscle,Ruffinis Corpuscles,Spindle, Neurotendinous,Spindles, Neurotendinous,Tendon Organ, Golgi,Tendon Organs, Golgi
D008815	Mice, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.	Inbred Mouse Strains,Inbred Strain of Mice,Inbred Strain of Mouse,Inbred Strains of Mice,Mouse, Inbred Strain,Inbred Mouse Strain,Mouse Inbred Strain,Mouse Inbred Strains,Mouse Strain, Inbred,Mouse Strains, Inbred,Strain, Inbred Mouse,Strains, Inbred Mouse
D008959	Models, Neurological	Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.	Neurologic Models,Model, Neurological,Neurologic Model,Neurological Model,Neurological Models,Model, Neurologic,Models, Neurologic
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
D010791	Phrenic Nerve	The motor nerve of the diaphragm. The phrenic nerve fibers originate in the cervical spinal column (mostly C4) and travel through the cervical plexus to the diaphragm.	Nerve, Phrenic,Nerves, Phrenic,Phrenic Nerves
D011311	Pressoreceptors	Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.	Baroreceptors,Receptors, Stretch, Arterial,Receptors, Stretch, Vascular,Stretch Receptors, Arterial,Stretch Receptors, Vascular,Arterial Stretch Receptor,Arterial Stretch Receptors,Baroreceptor,Pressoreceptor,Receptor, Arterial Stretch,Receptor, Vascular Stretch,Receptors, Arterial Stretch,Receptors, Vascular Stretch,Stretch Receptor, Arterial,Stretch Receptor, Vascular,Vascular Stretch Receptor,Vascular Stretch Receptors
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D001920	Bradykinin	A nonapeptide messenger that is enzymatically produced from KALLIDIN in the blood where it is a potent but short-lived agent of arteriolar dilation and increased capillary permeability. Bradykinin is also released from MAST CELLS during asthma attacks, from gut walls as a gastrointestinal vasodilator, from damaged tissues as a pain signal, and may be a neurotransmitter.	Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg,Bradykinin Acetate, (9-D-Arg)-Isomer,Bradykinin Diacetate,Bradykinin Hydrochloride,Bradykinin Triacetate,Bradykinin, (1-D-Arg)-Isomer,Bradykinin, (2-D-Pro)-Isomer,Bradykinin, (2-D-Pro-3-D-Pro-7-D-Pro)-Isomer,Bradykinin, (2-D-Pro-7-D-Pro)-Isomer,Bradykinin, (3-D-Pro)-Isomer,Bradykinin, (3-D-Pro-7-D-Pro)-Isomer,Bradykinin, (5-D-Phe)-Isomer,Bradykinin, (5-D-Phe-8-D-Phe)-Isomer,Bradykinin, (6-D-Ser)-Isomer,Bradykinin, (7-D-Pro)-Isomer,Bradykinin, (8-D-Phe)-Isomer,Bradykinin, (9-D-Arg)-Isomer,Arg Pro Pro Gly Phe Ser Pro Phe Arg
D001931	Brain Mapping	Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.	Brain Electrical Activity Mapping,Functional Cerebral Localization,Topographic Brain Mapping,Brain Mapping, Topographic,Functional Cerebral Localizations,Mapping, Brain,Mapping, Topographic Brain