In situ injection of kainic acid: A new method for selectively lesioning neuronal cell bodies while sparing axons of passage

We studied in cats the long-term effects upon resting ventilation and the ventilatory responses to CO2 breathing of destruction of neuronal cell bodies within the ventrolateral nucleus of the tractus solitarius (vl-NTS) by kainic acid (KA) injection (KAI). Animals were studied in the awake state and under pentobarbital anesthesia both before and 8 wk after stereotaxic bilateral microinjection of the vl-NTS with mock cerebrospinal fluid (CSF) (controls, n = 2) or with KA in mock CSF (KAI, n = 5). KA reduced the number of cell bodies within the vl-NTS by 75%. Under anesthesia minute ventilation (VI) was reduced by 49% after KAI, due primarily to a 54% reduction in breathing frequency (f). Four of five anesthetized KAI animals exhibited a significantly reduced (P less than 0.01) ventilatory sensitivity to inspired CO2 under anesthesia. In the awake state some KAI animals had significant changes (P less than 0.01) in ventilation; VI reduced (2 of 5), tidal volume reduced (1 of 5), f reduced (3 of 5), and inspiratory and expiratory times increased (2 of 5). Decreases in the awake ventilatory CO2 sensitivity were not significant within individual KAI animals but were significant (P less than 0.05) when considered as a group. Thus following 75% neuronal loss within the vl-NTS, rhythmic ventilation was sustained during both anesthesia and wakefulness, although f was reduced in the former state. The vl-NTS may function to set most but not all of the ventilatory sensitivity to CO2 during anesthesia and to a lesser extent during wakefulness.

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Nucleus Gracilis: An Integrator for Visceral and Somatic Information

Journal of Neurophysiology ◽

10.1152/jn.1997.78.1.521 ◽

1997 ◽

Vol 78 (1) ◽

pp. 521-527 ◽

Cited By ~ 68

Author(s):

Elie D. Al-Chaer ◽

Karin N. Westlund ◽

William D. Willis

Keyword(s):

Kainic Acid ◽

Visceral Pain ◽

Neuronal Cell ◽

Dorsal Column ◽

Sprague Dawley ◽

Nucleus Gracilis ◽

Abdominal Organs ◽

Neuronal Cell Bodies ◽

Sprague Dawley Rats ◽

Before And After

Al-Chaer, Elie D., Karin N. Westlund, and William D. Willis. Nucleus gracilis: an integrator for visceral and somatic information. J. Neurophysiol. 78: 521–527, 1997. The nucleus gracilis (NG) receives an abundance of visceral input from various abdominal organs and is proposed to play an important role in visceral pain processing. The purpose of this study was to investigate the necessity of the NG for colorectal input into the ventral posterolateral (VPL) nucleus of the thalamus. Single-cell recordings were made from nine VPL cells isolated in nine different male Sprague Dawley rats anesthetized with pentobarbital sodium. Responses of the VPL cells to colorectal distension (CRD) and to cutaneous stimuli were obtained before and after lesioning of the NG. Electrolytic ( n = 5) and chemical ( n = 4) lesions of the NG were made in different preparations. The chemical lesions were made by injecting a solution of kainic acid into the NG. Kainic acid presumably kills neuronal cell bodies and spares axons of passage. The results indicate that a lesion of the NG, regardless of its type, reduces dramatically the responses of VPL neurons to innocuous cutaneous stimuli, and, to a lesser extent, the responses to CRD. Attenuation of VPL neuronal responses to CRD as well as to innocuous cutaneous stimuli by the NG lesions emphasizes the role of the dorsal column in visceral nociception and suggests that the NG is an integration center for visceral and cutaneous information flowing into the VPL nucleus.

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Specific detection of neuronal cell bodies: in situ hybridization with a biotin-labeled neurofilament cDNA probe.

Journal of Histochemistry & Cytochemistry ◽

10.1177/34.7.3458811 ◽

1986 ◽

Vol 34 (7) ◽

pp. 923-926 ◽

Cited By ~ 41

Author(s):

P Liesi ◽

J P Julien ◽

P Vilja ◽

F Grosveld ◽

L Rechardt

Keyword(s):

In Situ Hybridization ◽

Cdna Probe ◽

Neuronal Cell ◽

Dna Probe ◽

Specific Detection ◽

Neurofilament Protein ◽

Antibody Staining ◽

Neuronal Cell Bodies ◽

Specific Mrna

We have used a biotinylated, 300-nucleotide cDNA probe which encodes the 68,000 MW neurofilament protein to detect neurofilament-specific mRNA in situ. The neurofilament message specifically demonstrates the neuronal cell bodies, in contrast to the usual antibody staining which detects their neurites. The hybridization is detected only in neuronal structures. Consequently, detection of the biotinylated neurofilament DNA probe by silver-intensified streptavidin-gold can be specifically used to identify neuronal cell bodies.

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Gonadotropin-Inhibitory Hormone Neurons Interact Directly with Gonadotropin-Releasing Hormone-I and -II Neurons in European Starling Brain

Endocrinology ◽

10.1210/en.2007-0983 ◽

2007 ◽

Vol 149 (1) ◽

pp. 268-278 ◽

Cited By ~ 187

Author(s):

Takayoshi Ubuka ◽

Stephanie Kim ◽

Yu-chi Huang ◽

Jessica Reid ◽

Jennifer Jiang ◽

...

Keyword(s):

In Situ Hybridization ◽

Neuronal Activity ◽

Cellular Localization ◽

Neuronal Cell ◽

European Starling ◽

Inhibitory System ◽

Axon Terminals ◽

Neuronal Cell Bodies ◽

Gonadotropin Inhibitory Hormone

Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH2) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH2 by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland.

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Kainic acid on the rostral ventrolateral medulla inhibits phrenic output and CO2 sensitivity

Journal of Applied Physiology ◽

10.1152/jappl.1988.65.4.1525 ◽

1988 ◽

Vol 65 (4) ◽

pp. 1525-1534 ◽

Cited By ~ 29

Author(s):

E. E. Nattie ◽

J. W. Mills ◽

L. C. Ou ◽

W. M. St John

Keyword(s):

Kainic Acid ◽

Neuronal Cell ◽

Ventral Surface ◽

Ventrolateral Medulla ◽

Co2 Response ◽

Specific Amino Acid ◽

Amino Acid Receptors ◽

Neuronal Cell Bodies ◽

Chemosensitive Areas ◽

End Tidal

We used the neurotoxin, kainic acid, which is known to stimulate neuronal cell bodies as opposed to axons of passage by binding to specific amino acid receptors to determine whether cells with such receptors have access to the ventrolateral medullary surface and are involved in central ventilatory chemosensitivity. Pledgets with 4.7 mM kainic acid were placed bilaterally on the rostral, intermediate, or caudal ventilatory chemosensitive areas for 1-2 min in chloralose-urethan-anesthetized, paralyzed, vagotomized, glomectomized, and servo-ventilated cats. Application of kainic acid on the caudal or intermediate areas produced no consistent significant effects on eucapnic phrenic output or on the slope or maximum value of the phrenic nerve response to increased end-tidal PCO2. Rostral area kainic acid produced immediate augmentation and then diminution of blood pressure and phrenic output. Apnea developed in six of nine cats by 40 min. In all five cats in which it could be tested, the slope of the CO2 response was clearly decreased. Of [3H]kainic acid applied to the rostral area, 88.4% was shown to be within 2 mm of the ventral surface. Comparison of surface application sites of this and other studies suggests that an area overlapping the border of the original rostral and intermediate areas allows access to neurons involved in the chemoreception process, which may also provide tonic facilitatory input to cardiorespiratory systems.

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Characterization of Stanniocalcin-1 Receptors in the Rainbow Trout

ISRN Endocrinology ◽

10.5402/2012/257841 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Timothy D. J. Richards ◽

Amanda L. Fenton ◽

Rahma Syed ◽

Graham F. Wagner

Keyword(s):

Feedback Loop ◽

Gill Filament ◽

Neuronal Cell ◽

Binding Assays ◽

High Affinity ◽

Neuronal Cell Bodies ◽

The Matrix ◽

Unexpected Findings

Mammalian stanniocalcin-1 (STC-1) is one of several ligands targeted to mitochondria. High affinity STC-1 receptors are present on the mitochondrial membranes of nephron cells, myocytes, and hepatocytes, to enable ligand sequestration within the matrix. However, STC-1 receptors have not been characterized in fish. Nor is it known if mitochondrial targeting occurs in fish. The aim of the study was to address these questions. Saturation binding assays were carried out to obtain estimates of KD and Bmax. They revealed the presence of saturable, high-affinity receptors on both membranes and mitochondria of liver, muscle, and gill filament. In situ ligand binding (ISLB) was used to localize receptors at the histological level and revealed some unexpected findings. In cranium, for instance, receptors were found mainly in the cartilage matrix, as opposed to the chondrocytes. In brain, the majority of receptors were located on neuropil areas as opposed to neuronal cell bodies. In skeletal muscle, receptors were confined to periodic striations, tentatively identified as the Z lines. Receptors were even found on STC-1 producing corpuscles of Stannius cells, raising the possibility of there being an autocrine feedback loop or, perhaps, a soluble binding protein that is released with the ligand to regulate its bioavailability.

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Reduced Anorexigenic Efficacy of Leptin, But Not of the Melanocortin Receptor Agonist Melanotan-II, Predicts Diet-Induced Obesity in Rats

Endocrinology ◽

10.1210/en.2005-0472 ◽

2005 ◽

Vol 146 (12) ◽

pp. 5247-5256 ◽

Cited By ~ 8

Author(s):

Gertjan van Dijk ◽

Koert de Vries ◽

Csaba Nyakas ◽

Bauke Buwalda ◽

Tiziana Adage ◽

...

Keyword(s):

Insulin Resistance ◽

Visceral Obesity ◽

Neuronal Cell ◽

Liver Weight ◽

Ingestive Behavior ◽

Melanocortin Receptor ◽

Diet Induced Obesity ◽

Neuronal Cell Bodies ◽

Melanotan Ii

Leptin gains access to the central nervous system where it influences activity of neuronal networks involved in ingestive behavior, neuroendocrine activity, and metabolism. In particular, the brain melanocortin (MC) system is important in leptin signaling and maintenance of energy balance. Although leptin or MC receptor insensitivity has been proposed to be associated with obesity, the present study compared central leptin and MC receptor stimulation on some of the above-mentioned parameters and investigated whether these treatments predict proneness to diet-induced obesity (DIO) in outbred Wistar rats. Third-cerebroventricular administration of equi-anorexigenic doses of leptin and of the MC agonist melanotan-II caused comparable increases in plasma ACTH and corticosterone levels and c-Fos-labeling in approximately 70% of paraventricular hypothalamic (PVN) neuronal cell bodies containing CRH. This reinforces involvement of paraventricular CRH neurons in the short-term neuroendocrine and ingestive effects of leptin and melanocortins. In the DIO prediction study, anorexigenic efficacy of melanotan-II was not correlated with any parameter linked to DIO but was highly correlated with MC in situ binding (with labeled [Nle4,d-Phe7]α-MSH) as well as CRH immunoreactivity in the PVN of DIO rats. This suggests intricate relationships among MC signaling, the CRH system, and ingestive behavior unrelated to DIO. In the same animals, leptin’s anorexigenic efficacy was not correlated with PVN MC in situ binding or CRH immunoreactivity but correlated inversely to post-DIO plasma leptin, liver weight, and abdominal adiposity, the latter being correlated to insulin resistance. Thus, differences in leptin but not MC signaling might underlie DIO, visceral obesity, and insulin resistance.

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The Red Neuronal Pigment in the Nervous System of the Mussel, Mytilus Edulis: Localization and Its Effect on Lateral Ciliary Activity with Spectral and Analytical Changes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098952 ◽

1981 ◽

Vol 39 ◽

pp. 494-495

Author(s):

Anthony A. Paparo ◽

Judith A. Murphy

Keyword(s):

Nervous System ◽

Mytilus Edulis ◽

Neuronal Cell ◽

Ciliary Activity ◽

Neuronal Cell Bodies ◽

The Central Nervous System ◽

Intracellular Organelles ◽

The Common ◽

The Individual ◽

Cryostat Sections

The purpose of this study was to localize the red neuronal pigment in Mytilus edulis and examine its role in the control of lateral ciliary activity in the gill. The visceral ganglia (Vg) in the central nervous system show an over al red pigmentation. Most red pigments examined in squash preps and cryostat sec tions were localized in the neuronal cell bodies and proximal axon regions. Unstained cryostat sections showed highly localized patches of this pigment scattered throughout the cells in the form of dense granular masses about 5-7 um in diameter, with the individual granules ranging from 0.6-1.3 um in diame ter. Tissue stained with Gomori's method for Fe showed bright blue granular masses of about the same size and structure as previously seen in unstained cryostat sections.Thick section microanalysis (Fig.l) confirmed both the localization and presence of Fe in the nerve cell. These nerve cells of the Vg share with other pigmented photosensitive cells the common cytostructural feature of localization of absorbing molecules in intracellular organelles where they are tightly ordered in fine substructures.

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