Organization of orosensory responses in the nucleus of the solitary tract of rat

1. The receptive field and topographic organization of single orosensory neurons located throughout the rostral division of the nucleus of the solitary tract (rNST) was studied by determining their responsiveness to gustatory stimulation of the entire oral cavity and to gustatory and mechanical stimulation of restricted oral regions. The rNST contained roughly equal numbers of two distinct populations of orosensory neurons, one responsive exclusively to oral mechanical stimulation (M neurons), the other to gustatory stimulation (G neurons). Some G neurons also responded to oral somatosensory stimuli, but usually less vigorously than to gustatory stimuli. The distribution of these two populations of rNST neurons was topographically organized: G neurons were centered anteriorly and medially to M neurons. 2. Eight of 44 G neurons responded only when the whole oral cavity was stimulated, but the remaining 36 cells responded to circumscribed stimulation of taste buds on the anterior tongue (AT), foliate papillae of the posterior tongue, nasoincisor ducts, retromolar mucosa (RM), or soft palate (SP). Overall, AT and SP stimulation were the most effective, and RM stimulation the least effective, for activating nucleus of the solitary tract (NST) G neurons. 3. Approximately half of the G neurons for which a receptive field could be defined (N = 36) responded to stimulation of a single taste receptor subpopulation, but the remaining neurons received convergent input from two or more taste bud groups. The receptive field configurations for convergent G neurons were orderly: convergence occurred preferentially between receptor subpopulations either within the anterior oral cavity (AO) or the posterior oral cavity (PO). An AO-PO distinction also was reflected in the topographic organization of gustatory responses. The mean location of neurons responding optimally to AO gustatory stimulation was more anterior in the NST, and also tended to be more lateral and ventral than the location of neurons that responded optimally to PO stimulation. 4. Forty-four rNST M neurons responded to innocuous mechanical stimulation of restricted areas of the tongue, palate, buccal mucosa, or periodontium. Stimulation of the hard palate and circumvallate papilla were most effective, whereas periodontal stimulation was least effective for activating these cells. 5. A majority (32 of 44) of rNST M neurons responded to stimulation of more than one of the oral sites tested.(ABSTRACT TRUNCATED AT 400 WORDS)

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Anterior and Posterior Oral Cavity Responsive Neurons Are Differentially Distributed Among Parabrachial Subnuclei in Rat

Journal of Neurophysiology ◽

10.1152/jn.1997.78.2.920 ◽

1997 ◽

Vol 78 (2) ◽

pp. 920-938 ◽

Cited By ~ 77

Author(s):

Christopher B. Halsell ◽

Susan P. Travers

Keyword(s):

Oral Cavity ◽

Taste Receptor ◽

Hierarchical Cluster ◽

Response Rates ◽

Differential Sensitivity ◽

Response Profiles ◽

To Receive ◽

Gustatory Neurons ◽

Comparable Population ◽

Stimulation Of

Halsell, Christopher B. and Susan P. Travers. Anterior and posterior oral cavity responsive neurons are differentially distributed among parabrachial subnuclei in rat. J. Neurophysiol. 78: 920–938, 1997. The responses of single parabrachial nucleus (PBN) neurons were recorded extracellularly to characterize their sensitivity to stimulation of individual gustatory receptor subpopulations (G neurons, n = 75) or mechanical stimulation of defined oral regions (M neurons, n = 54) then localized to morphologically defined PBN subdivisions. Convergence from separate oral regions onto single neurons occurred frequently for both G and M neurons, but converging influences were more potent when they arose from nearby locations confined to the anterior (AO) or posterior oral cavity (PO). A greater number of G neurons responded optimally to stimulation of AO than to PO receptor subpopulations, and these AO-best G neurons had higher spontaneous and evoked response rates but were less likely to receive convergent input than PO-best G neurons. In contrast, proportions, response rates, and convergence patterns of AO- and PO-best M neurons were more comparable. The differential sensitivity of taste receptor subpopulations was reflected in PBN responses. AO stimulation with NaCl elicited larger responses than PO stimulation; the converse was true for QHCl stimulation. Within the AO, NaCl elicited a larger response when applied to the anterior tongue than to the nasoincisor duct. Hierarchical cluster analysis of chemosensitive response profiles suggested two groups of PBN G neurons. One group was composed of neurons optimally responsive to NaCl (N cluster); the other to HCl (H cluster). Most N- and H-cluster neurons were AO-best. Although they were more heterogenous, all but one of the remaining G neurons were unique in responding best or second-best to quinine and so were designated as quinine sensitive (Q+). Twice as many Q+ neurons were PO- compared with AO-best. M neurons were scattered across PBN subdivisions, but G neurons were concentrated in two pairs of subdivisions. The central medial and ventral lateral subdivisions contained both G and M neurons but were dominated by AO-best N-cluster G neurons. The distribution of G neurons in these subdivisions appeared similar to distributions in most previous studies of PBN gustatory neurons. In contrast to earlier studies, however, the external medial and external lateral-inner subdivisions also contained G neurons, intermingled with a comparable population of M neurons. Unlike cells in the central medial and ventral lateral subnuclei, nearly every neuron in the external subnuclei was PO best, and only one was an N-cluster cell. In conclusion, the present study supports a functional distinction between sensory input from the AO and PO at the pontine level, which may represent an organizing principle throughout the gustatory neuraxis. Furthermore, two morphologically distinct pontine regions containing orosensory neurons are described.

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Patterns of responses of neurons in cuneate nucleus to controlled mechanical stimulation of cutaneous velocity receptors in the cat

Journal of Neurophysiology ◽

10.1152/jn.1980.43.6.1673 ◽

1980 ◽

Vol 43 (6) ◽

pp. 1673-1699 ◽

Cited By ~ 19

Author(s):

V. Golovchinsky

Keyword(s):

Receptive Field ◽

Mechanical Stimulation ◽

Receptive Fields ◽

Neuronal Firing ◽

High Threshold ◽

Pacinian Corpuscles ◽

Sharp Separation ◽

First Order ◽

Discharge Patterns ◽

Stimulation Of

1. The responses of single cuneate neurons to controled mechanical stimulation of skin were recorded in cats lightly anesthetized with a nitrous oxide-halothane mixture. The discharge patterns and peripheral receptive-field characteristics were studied in neurons driven by sensitive cutaneous mechanoreceptors, including slowly adapting skin mechanoreceptors. Virtually all cuneate neurons display maximum discharge during the velocity component of displacement. 2. Among cuneate neurons encountered in this study, approximately 46% were driven by guard hair mechanoreceptors, 15% were driven by field receptors, and 13% were driven by slowly adapting skin receptors. Neurons responding to stimulation of deep tissues (including claws) were not studied with controlled mechanical stimulation and accounted for 19%. The rest of the neurons were driven by Pacinian corpuscles, received afferent inputs from several different first-order afferents, or were not definitely identified. There was no clear evidence of down hair or high-threshold mechanoreceptor representation. 3. The discharge pattern in response to a constant-velocity stimulus proved most valuable in describing submodality classes of neurons driven by hair and field receptors since sensitivity of these neurons to dynamic and to static phases of stimulation constitute respective continua and, thus, preclude sharp separation into distinct groups. 4. The majority of neurons displayed response properties and receptive fields similar to those of first-order afferents. A minority of cells had receptive fields that were larger than those of primary afferents, with nearly identical modality and velocity characteristics throughout the receptive field. 5. Approximately 2% of recorded neurons displayed convergent properties not encountered in first-order afferents, including neurons driven from receptors of different modalities or from discontinuous receptive fields. 6. Inhibition of neuronal firing generated from outside the receptive field was rarely seen, possibly due to anesthetic conditions. In a small number of neurons, irregularities in the discharge were observed that might indicate inhibitory influences originating from within the receptive field.

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Two Types of Rhythmical Jaw Movements Produced by Mechanical Stimulation of the Oral Cavity.

Japanese Journal of Oral Biology ◽

10.2330/joralbiosci1965.43.189 ◽

2001 ◽

Vol 43 (2) ◽

pp. 189-193

Author(s):

Kazushige Sasamoto ◽

Yuzo Ninomiya

Keyword(s):

Oral Cavity ◽

Mechanical Stimulation ◽

Jaw Movements ◽

Stimulation Of

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Topographic organization of Fos-like immunoreactivity in the rostral nucleus of the solitary tract evoked by gustatory stimulation with sucrose and quinine

Brain Research ◽

10.1016/0006-8993(95)01410-1 ◽

1996 ◽

Vol 711 (1-2) ◽

pp. 125-137 ◽

Cited By ~ 81

Author(s):

Marie I. Harrer ◽

Susan P. Travers

Keyword(s):

Solitary Tract ◽

Topographic Organization ◽

Gustatory Stimulation ◽

Rostral Nucleus

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Mechanical stimulation of human BON cells: Gαq involvement in 5-HT release

Gastroenterology ◽

10.1016/s0016-5085(01)80410-8 ◽

2001 ◽

Vol 120 (5) ◽

pp. A83-A83

Author(s):

M KIM ◽

N JAVED ◽

F CHRISTOFI ◽

H COOKE

Keyword(s):

Mechanical Stimulation ◽

Bon Cells ◽

Stimulation Of

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Neural mechanisms of hepatic blood flow response to noxious mechanical stimulation of skin in anesthetized rats

Neuroscience Research ◽

10.1016/s0168-0102(00)81890-8 ◽

2000 ◽

Vol 38 ◽

pp. S174

Author(s):

K Enomoto

Keyword(s):

Blood Flow ◽

Hepatic Blood Flow ◽

Mechanical Stimulation ◽

Neural Mechanisms ◽

Blood Flow Response ◽

Flow Response ◽

Anesthetized Rats ◽

Noxious Mechanical Stimulation ◽

Stimulation Of

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Use of Flexible Materials with a Novel Pressure Driven Equibiaxial Cell Stretching Device for Mechanical Stimulation of Single Mammalian Cells

MRS Proceedings ◽

10.1557/proc-773-n5.6 ◽

2003 ◽

Vol 773 ◽

Author(s):

James D. Kubicek ◽

Stephanie Brelsford ◽

Philip R. LeDuc

Keyword(s):

Cell Fate ◽

Mechanical Stimulation ◽

Mammalian Cells ◽

Cellular Response ◽

Single Cells ◽

Complex Nature ◽

Cellular Behavior ◽

Cell Stretching ◽

Stimulation Of ◽

Pressure Driven

AbstractMechanical stimulation of single cells has been shown to affect cellular behavior from the molecular scale to ultimate cell fate including apoptosis and proliferation. In this, the ability to control the spatiotemporal application of force on cells through their extracellular matrix connections is critical to understand the cellular response of mechanotransduction. Here, we develop and utilize a novel pressure-driven equibiaxial cell stretching device (PECS) combined with an elastomeric material to control specifically the mechanical stimulation on single cells. Cells were cultured on silicone membranes coated with molecular matrices and then a uniform pressure was introduced to the opposite surface of the membrane to stretch single cells equibiaxially. This allowed us to apply mechanical deformation to investigate the complex nature of cell shape and structure. These results will enhance our knowledge of cellular and molecular function as well as provide insights into fields including biomechanics, tissue engineering, and drug discovery.

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