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Yokoyama T, Ito M, Yamamoto Y, Hirakawa M, Sakanoue W, Sato K, Saino T. Immunolocalization of vesicular glutamate transporter 2 and exocytosis-related proteins in afferent nerve endings innervating taste buds in the rat incisive papilla. Anat Histol Embryol 2023. [PMID: 36825501 DOI: 10.1111/ahe.12911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/17/2023] [Accepted: 02/07/2023] [Indexed: 02/25/2023]
Abstract
The present study aimed to investigate the immunolocalization of vesicular glutamate transporter (VGLUT) 1 and 2, and proteins associated with exocytosis, i.e., core components of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor complex (synaptosomal-associated protein of 25 kDa, syntaxin 1, and vesicle-associated membrane protein 2) and synaptotagmin-1 (Syt1), in incisive papillary taste buds of rats using double-indirect immunofluorescence. No VGLUT1 immunoreactivity was observed, whereas VGLUT2-immunoreactive punctate products were closely associated with guanine nucleotide-binding protein G(t) subunit α3-immmunoreactive cells in taste buds. VGLUT2 was immunolocalized in P2X3 purinoceptor-expressing afferent nerve endings. Synaptosomal-associated protein of 25 kDa, syntaxin 1, and vesicle-associated membrane protein 2 were immunolocalized in nerve endings containing VGLUT2-immunoreactive products as well as a few cells in taste buds. VGLUT2 was co-immunolocalized in some intragemmal nerve endings immunoreactive for Syt1, a calcium sensor implicated in vesicle membrane fusion. The present results suggest that afferent nerve endings innervating incisive taste buds release glutamate by exocytosis to modulate taste cell function.
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Affiliation(s)
- Takuya Yokoyama
- Department of Anatomy (Cell Biology), Iwate Medical University, Yahaba, Japan
| | - Motoi Ito
- Division of Dental Anesthesiology, Department of Reconstructive Oral and Maxillofacial Surgery, School of Dentistry, Iwate Medical University, Yahaba, Japan
| | - Yoshio Yamamoto
- Laboratory of Veterinary Anatomy and Cell Biology, Faculty of Agriculture, Iwate University, Morioka, Japan
| | - Masato Hirakawa
- Department of Anatomy (Cell Biology), Iwate Medical University, Yahaba, Japan
| | - Wakana Sakanoue
- Division of Dental Anesthesiology, Department of Reconstructive Oral and Maxillofacial Surgery, School of Dentistry, Iwate Medical University, Yahaba, Japan
| | - Kenichi Sato
- Division of Dental Anesthesiology, Department of Reconstructive Oral and Maxillofacial Surgery, School of Dentistry, Iwate Medical University, Yahaba, Japan
| | - Tomoyuki Saino
- Department of Anatomy (Cell Biology), Iwate Medical University, Yahaba, Japan
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Ito M, Yokoyama T, Hirakawa M, Yamamoto Y, Sakanoue W, Sato K, Saino T. Morphology and chemical characteristics of taste buds associated with P2X3-immunoreactive afferent nerve endings in the rat incisive papilla. J Anat 2022; 240:688-699. [PMID: 34719779 PMCID: PMC8930809 DOI: 10.1111/joa.13583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/16/2021] [Accepted: 10/22/2021] [Indexed: 11/30/2022] Open
Abstract
The present study investigated the cellular components and afferent innervations of taste buds in the rat incisive papilla by immunohistochemistry using confocal scanning laser microscopy. Taste buds containing guanine nucleotide-binding protein G(t), subunit α3 (GNAT3)-imunoreactive cells were densely distributed in the lateral wall of incisive papilla forming the opening of nasoincisor ducts. GNAT3-immunoreactive cells in the taste buds were slender in shape and the tips of apical processes gathered at one point at the surface of the epithelium. The number of taste buds was 56.8 ± 4.5 in the incisive papilla. The incisive taste buds also contained ectonucleoside triphosphate diphosphohydrolase 2-immunoreactive cells and synaptotagmin-1-immunoreactive cells in addition to GNAT3-immunoreactive cells. Furthermore, GNAT3-immunoreactive cells were immunoreactive to taste transduction molecules such as phospholipase C, β2-subunit, and inositol 1,4,5-trisphosphate receptor, type 3. P2X3-immunoreactive subepithelial nerve fibers intruded into the taste buds and terminated with hederiform or calix-like nerve endings attached to GNAT3-immunoreactive cells and synaptosomal-associated protein, 25 kDa-immunoreactive cells. Some P2X3-immunoreactive endings were also weakly immunoreactive for P2X2. Furthermore, a retrograde tracing method using fast blue dye indicated that most of the P2X3-immunoreactive nerve endings originated from the geniculate ganglia (GG) of the facial nerve. These results suggest that incisive taste buds are morphologically and cellularly homologous to lingual taste buds and are innervated by P2X3-immunoreactive nerve endings derived from the GG. The incisive papilla may be the palatal taste papilla that transmits chemosensory information in the oral cavity to the GG via P2X3-immunoreactive afferent nerve endings.
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Affiliation(s)
- Motoi Ito
- Division of Dental AnesthesiologyDepartment of Reconstructive Oral and Maxillofacial SurgerySchool of DentistryIwate Medical UniversityYahabaJapan
| | - Takuya Yokoyama
- Department of Anatomy (Cell Biology)Iwate Medical UniversityYahabaJapan
| | - Masato Hirakawa
- Department of Anatomy (Cell Biology)Iwate Medical UniversityYahabaJapan
| | - Yoshio Yamamoto
- Laboratory of Veterinary Anatomy and Cell BiologyFaculty of AgricultureIwate UniversityMoriokaJapan
| | - Wakana Sakanoue
- Division of Dental AnesthesiologyDepartment of Reconstructive Oral and Maxillofacial SurgerySchool of DentistryIwate Medical UniversityYahabaJapan
| | - Kenichi Sato
- Division of Dental AnesthesiologyDepartment of Reconstructive Oral and Maxillofacial SurgerySchool of DentistryIwate Medical UniversityYahabaJapan
| | - Tomoyuki Saino
- Department of Anatomy (Cell Biology)Iwate Medical UniversityYahabaJapan
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Kawashima M, Imura K, Sato I. Topographical organization of TRPV1-immunoreactive epithelium and CGRP-immunoreactive nerve terminals in rodent tongue. Eur J Histochem 2012; 56:e21. [PMID: 22688302 DOI: 10.4081/ejh.2012.21] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 03/10/2012] [Accepted: 03/12/2012] [Indexed: 11/22/2022] Open
Abstract
Transient receptor potential vanilloid subfamily member 1 (TRPV1) is activated by capsaicin, acid, and heat and mediates pain through peripheral nerves. In the tongue, TRPV1 expression has been reported also in the epithelium. This indicates a possibility that sensation is first received by the epithelium. However, how nerves receive sensations from the epithelium remains unclear. To clarify the anatomical basis of this interaction, we performed immunohistochemical studies in the rodent tongue to detect TRPV1 and calcitonin gene-related peptide (CGRP), a neural marker. Strong expression of TRPV1 in the epithelium was observed and was restricted to the apex of the tongue. Double immunohistochemical staining revealed that CGRP-expressing nerve terminals were in close apposition to the strongly TRPV1-expressing epithelium of fungiform papilla in the apex of rodent tongues. These results suggest that the TRPV1-expressing epithelium monitors the oral environment and acquired information may then be conducted to the adjacent CGRP-expressing terminals.
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Affiliation(s)
- M Kawashima
- Department of Anatomy, School of Life Dentistry at Tokyo, The Nippon Dental University, Tokyo, Japan
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Haas HS, Linecker A, Pfragner R, Sadjak A. Peripheral glutamate signaling in head and neck areas. Head Neck 2011; 32:1554-72. [PMID: 20848447 DOI: 10.1002/hed.21438] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The major excitatory neurotransmitter glutamate is also found in the periphery in an increasing number of nonexcitable cells. In line with this it became apparent that glutamate can regulate a broad array of peripheral biological responses, as well. Of particular interest is the discovery that glutamate receptor reactive reagents can influence tumor biology. However, the knowledge of glutamate signaling in peripheral tissues is still incomplete and, in the case of head and neck areas, is almost lacking. The roles of glutamate signaling pathways in these regions are manifold and include orofacial pain, periodontal bone production, skin and airway inflammation, as well as salivation. Furthermore, the interrelations between glutamate and cancers in the oral cavity, thyroid gland, and other regions are discussed. In summary, this review shall strengthen the view that glutamate receptor reagents may also be promising targets for novel therapeutic concepts suitable for a number of diseases in peripheral tissues. The contents of this review cover the following sections: Introduction; The "Glutamate System"; The Taste of Glutamate; Glutamate Signaling in Dental Regions; Glutamate Signaling in Head and Neck Areas; Glutamate Signaling in Head and Neck Cancer; A Brief Overview of Glutamate Signaling in Other Cancers; and Conclusion.
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Affiliation(s)
- Helga Susanne Haas
- Department of Pathophysiology and Immunology, Center of Molecular Medicine, Medical University of Graz, Graz, Austria.
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Nakamura S, Bradley RM. Characteristics of calcium currents in rat geniculate ganglion neurons. J Neurophysiol 2011; 105:224-34. [PMID: 21068265 PMCID: PMC3023367 DOI: 10.1152/jn.00636.2010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 11/08/2010] [Indexed: 11/22/2022] Open
Abstract
Geniculate ganglion (GG) cell bodies of chorda tympani (CT), greater superficial petrosal (GSP), and posterior auricular (PA) nerves transmit orofacial sensory information to the rostral nucleus of the solitary tract (rNST). We used whole cell recording to study the characteristics of the Ca(2+) channels in isolated Fluorogold-labeled GG neurons that innervate different peripheral receptive fields. PA neurons were significantly larger than CT and GSP neurons, and CT neurons could be further subdivided based on soma diameter. Although all GG neurons possess both low voltage-activated (LVA) "T-type" and high voltage-activated (HVA) Ca(2+) currents, CT, GSP, and PA neurons have distinctly different Ca(2+) current expression patterns. Of GG neurons that express T-type currents, the CT and GSP neurons had moderate and PA neurons had larger amplitude T-type currents. HVA Ca(2+) currents in the GG neurons were separated into several groups using specific Ca(2+) channel blockers. Sequential applications of L, N, and P/Q-type channel antagonists inhibited portions of Ca(2+) current in all CT, GSP, and PA neurons to a different extent in each neuron group. No difference was observed in the percentage of L- and N-type Ca(2+) currents reduced by the antagonists in CT, GSP, and PA neurons. Action potentials in GG neurons are followed by a Ca(2+) current initiated after depolarization (ADP) that may influence intrinsic firing patterns. These results show that based on Ca(2+) channel expression the GG contains a heterogeneous population of sensory neurons possibly related to the type of sensory information they relay to the rNST.
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Affiliation(s)
- Shiro Nakamura
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA
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San Gabriel A, Nakamura E, Uneyama H, Torii K. Taste, visceral information and exocrine reflexes with glutamate through umami receptors. THE JOURNAL OF MEDICAL INVESTIGATION 2010; 56 Suppl:209-17. [PMID: 20224183 DOI: 10.2152/jmi.56.209] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Chemical substances of foods drive the cognitive recognition of taste with the subsequent regulation of digestion in the gastrointestinal (GI) tract. Tastants like glutamate can bind to taste membrane receptors on the tip of specialized taste cells eliciting umami taste. In chemical-sensing cells diffused through the GI tract, glutamate induces functional changes. Most of the taste-like receptor-expressing cells from the stomach and intestine are neuroendocrine cells. The signaling molecules produced by these neuroendocrine cells either activate afferent nerve endings or release peptide hormones that can regulate neighboring cells in a paracrine fashion or travel through blood to their target receptor. Once afferent sensory fibers transfer the chemical information of the GI content to the central nervous system (CNS) facilitating the gut-brain signaling, the CNS regulates the GI through efferent cholinergic and noradrenergic fibers. Thus, this is a two-way extrinsic communication process. Glutamate within the lumen of the stomach stimulates afferent fibers and increases acid and pepsinogen release; whereas on the duodenum, glutamate increases the production of mucous to protect the mucosa against the incoming gastric acid. The effects of glutamate are believed to be mediated by G protein-coupled receptors expressed at the lumen of GI cells. The specific cell-type and molecular function of each of these receptors are not completely known. Here we will examine some of the glutamate receptors and their already understood role on GI function regulation.
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Affiliation(s)
- Ana San Gabriel
- Institute of Life Sciences, Ajinomoto Co., Inc., Kawasaki, Japan
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Vandenbeuch A, Tizzano M, Anderson CB, Stone LM, Goldberg D, Kinnamon SC. Evidence for a role of glutamate as an efferent transmitter in taste buds. BMC Neurosci 2010; 11:77. [PMID: 20565975 PMCID: PMC2898831 DOI: 10.1186/1471-2202-11-77] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 06/21/2010] [Indexed: 01/30/2023] Open
Abstract
Background Glutamate has been proposed as a transmitter in the peripheral taste system in addition to its well-documented role as an umami taste stimulus. Evidence for a role as a transmitter includes the presence of ionotropic glutamate receptors in nerve fibers and taste cells, as well as the expression of the glutamate transporter GLAST in Type I taste cells. However, the source and targets of glutamate in lingual tissue are unclear. In the present study, we used molecular, physiological and immunohistochemical methods to investigate the origin of glutamate as well as the targeted receptors in taste buds. Results Using molecular and immunohistochemical techniques, we show that the vesicular transporters for glutamate, VGLUT 1 and 2, but not VGLUT3, are expressed in the nerve fibers surrounding taste buds but likely not in taste cells themselves. Further, we show that P2X2, a specific marker for gustatory but not trigeminal fibers, co-localizes with VGLUT2, suggesting the VGLUT-expressing nerve fibers are of gustatory origin. Calcium imaging indicates that GAD67-GFP Type III taste cells, but not T1R3-GFP Type II cells, respond to glutamate at concentrations expected for a glutamate transmitter, and further, that these responses are partially blocked by NBQX, a specific AMPA/Kainate receptor antagonist. RT-PCR and immunohistochemistry confirm the presence of the Kainate receptor GluR7 in Type III taste cells, suggesting it may be a target of glutamate released from gustatory nerve fibers. Conclusions Taken together, the results suggest that glutamate may be released from gustatory nerve fibers using a vesicular mechanism to modulate Type III taste cells via GluR7.
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Raliou M, Wiencis A, Pillias AM, Planchais A, Eloit C, Boucher Y, Trotier D, Montmayeur JP, Faurion A. Nonsynonymous single nucleotide polymorphisms in human tas1r1, tas1r3, and mGluR1 and individual taste sensitivity to glutamate. Am J Clin Nutr 2009; 90:789S-799S. [PMID: 19571223 DOI: 10.3945/ajcn.2009.27462p] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Several studies indicate an essential role of the heterodimer Tas1R1-Tas1R3 for monosodium l-glutamate (MSG) detection, although others suggest alternative receptors. Human subjects show different taste sensitivities to MSG, and some are unable to detect the presence of glutamate. Our objective was to study possible relations between phenotype (sensitivity to glutamate) and genotype (polymorphisms in candidate glutamate taste receptors tas1r1, tas1r3, mGluR4, and mGluR1) at the individual level. The sensitivity was measured with a battery of tests to distinguish the effect of sodium ions from the effect of glutamate ions in MSG. A total of 142 genetically unrelated white French subjects were categorized into 27 nontasters (specific ageusia), 21 hypotasters, and 94 tasters. Reverse transcriptase polymerase chain reaction and immunohistochemistry showed expression of tas1r1, tas1r3, and alpha-gustducin in fungiform papillae in all 12 subjects tested, including subjects who presented specific ageusia for glutamate. Amplification and sequencing of cDNA and genomic DNA allowed the identification of 10 nonsynonymous single nucleotide polymorphisms (nsSNPs) in tas1r1 (n = 3), tas1r3 (n = 3), and mGluR1 (n = 4). In our sample of subjects, the frequencies of 2 nsSNPs, C329T in tas1r1 and C2269T in tas1r3, were significantly higher in nontasters than expected, whereas G1114A in tas1r1 was more frequent in tasters. These nsSNPs along with minor variants and other nsSNPs in mGluR1, including T2977C, account for only part of the interindividual variance, which indicates that other factors, possibly including additional receptors, contribute to glutamate sensitivity.
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Affiliation(s)
- Mariam Raliou
- NBS-NOPA, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
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Cocores JA, Gold MS. The Salted Food Addiction Hypothesis may explain overeating and the obesity epidemic. Med Hypotheses 2009; 73:892-9. [PMID: 19643550 DOI: 10.1016/j.mehy.2009.06.049] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Accepted: 06/28/2009] [Indexed: 11/19/2022]
Abstract
UNLABELLED One plausible explanation for the controversy that surrounds the causes and clinical management of obesity is the notion that overeating and obesity may only be a couple of "symptoms" associated with a yet to be discovered medical disorder. OBJECTIVES To introduce the Salted Food Addition Hypothesis. This theory proposes that salted food acts in the brain like an opiate agonist, producing a hedonic reward which has been perceived as being only peripherally "flavorful", "tasty" or "delicious". The Salted Food Addition Hypothesis also proposes that opiate receptor withdrawal has been perceived as "preference," "urges," "craving" or "hunger" for salted food. METHODS The Salted Food Addiction Hypothesis is made manifest by individually presenting a basic review of its primary coexisting components; the Neurological Component and the Psychosocial Component. We also designed a prospective study in order to test our hypothesis that opiate dependent subjects increase their consumption of salted food during opiate withdrawal. RESULTS The neuropsychiatric evidence integrated here suggests that salted food acts like an, albeit mild, opiate agonist which drives overeating and weight gain. The opiate dependent group studied (N=27) developed a 6.6% increase in weight during opiate withdrawal. CONCLUSIONS Salted Food may be an addictive substance that stimulates opiate and dopamine receptors in the brain's reward and pleasure center more than it is "tasty", while salted food preference, urge, craving and hunger may be manifestations of opiate withdrawal. Salted food and opiate withdrawal stimulate appetite, increases calorie consumption, augments the incidence of overeating, overweight, obesity and related illnesses. Obesity and related illnesses may be symptoms of Salted Food Addiction.
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Affiliation(s)
- James A Cocores
- Department of Psychiatry, University of Florida College of Medicine & McKnight Brain Institute, Gainesville, FL, USA.
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Huesa G, Ikenaga T, Böttger B, Finger TE. Calcium-fluxing glutamate receptors associated with primary gustatory afferent terminals in goldfish (Carassius auratus). J Comp Neurol 2008; 506:694-707. [PMID: 18067143 DOI: 10.1002/cne.21571] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Presynaptic ionotropic glutamate receptors modulate transmission at primary afferent synapses in several glutamatergic systems. To test whether primary gustatory afferent fibers express Ca(2+)-permeable AMPA/kainate receptors, we utilized kainate-stimulated uptake of Co(2+) along with immunocytochemistry for the Ca(2+)-binding proteins (CaBPs) calbindin and calretinin to investigate the primary gustatory afferents in goldfish (Carassius auratus). In goldfish, the primary gustatory nucleus (equivalent to the gustatory portion of the nucleus of the solitary tract) includes the vagal lobe, which is a large, laminated structure protruding dorsally from the medulla. Kainate-stimulated uptake of Co(2+) (a measure of Ca(2+)-fluxing glutamate receptors) shows punctate staining distributed in the distinct laminar pattern matching the layers of termination of the primary gustatory afferent fibers. In addition, CaBP immunocytochemistry, which correlates highly with expression of Ca(2+)-permeable AMPA/kainate receptors, shows a laminar pattern of distribution similar to that found with kainate-stimulated cobalt uptake. Nearly all neurons of the vagal gustatory ganglion show Co(2+) uptake and are immunopositive for CaBPs. Transection of the vagus nerve proximal to the ganglion results in loss of such punctate Co(2+) uptake and of punctate CaBP staining as soon as 4 days postlesion. These results are consonant with the presence of Ca(2+)-fluxing glutamate receptors on the presynaptic terminals of primary gustatory terminals, providing an avenue for modulation of primary gustatory input.
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Affiliation(s)
- Gema Huesa
- Department of Cell and Developmental Biology, School of Medicine, University Colorado at Denver, Aurora, Colorado 80045, USA
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Carr VM, Sollars SI, Farbman AI. Neuronal cell death and population dynamics in the developing rat geniculate ganglion. Neuroscience 2005; 134:1301-8. [PMID: 16054764 DOI: 10.1016/j.neuroscience.2005.05.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2005] [Accepted: 05/19/2005] [Indexed: 11/24/2022]
Abstract
In contrast to many neuronal systems, the pattern of developmental neuronal degeneration in the rat geniculate ganglion has remained undefined. To address this issue sectioned geniculate ganglia from embryonic day 13 to postnatal day 3 have been examined using standard histological techniques, TdT-mediated dUTP-digoxigenin nick end labeling to verify apoptotic activity, bromo-deoxyuridine incorporation to monitor neuronal precursor proliferation, and anti-beta-neurotubulin III to verify the neuronal identity of pycnotic cells. Results summed from alternate (embryonic day 13) or every third (embryonic day 14-postnatal day 3) section show that neuronal degeneration occurs as early as embryonic day 13 (6.8% of neurons counted), well before geniculate innervation of lingual taste buds at embryonic day 16. A degenerative peak occurs at embryonic day 17 (9.5%) followed by a decline (1.7% at embryonic day 18) and leveling off (0.1%-0.2% at embryonic day 22-postnatal day 3). Thus, geniculate neuronal degenerative pattern includes both innervation-associated histogenetic and morphogenetic cell death. Corresponding counts of mean neuronal numbers in the sections showed a continual rise from embryonic day 13 through embryonic day 18 (approx. 330-760) followed by a slight decline at embryonic day 19 (to approx. 630) and then a final leveling off at 800-825 by embryonic day 20. This pattern differs from many other developing neural systems which show a major population crash during initial target contact. It likely reflects different but slightly overlapping neuronal precursor proliferation and degeneration patterns in multiple geniculate neuronal subpopulations.
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Affiliation(s)
- V McM Carr
- Department of Neurobiology and Physiology, Northwestern University, Evanston, IL 60208-3520, USA.
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