1
|
Chen SP, Fuh JL, Chung MY, Lin YC, Liao YC, Wang YF, Hsu CL, Yang UC, Lin MW, Chiou JJ, Wang PJ, Chen PK, Fan PC, Wu JY, Chen YT, Kao LS, Shen-Jang Fann C, Wang SJ. Genome-wide association study identifies novel susceptibility loci for migraine in Han Chinese resided in Taiwan. Cephalalgia 2017; 38:466-475. [PMID: 28952330 DOI: 10.1177/0333102417695105] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Background Susceptibility genes for migraine, despite it being a highly prevalent and disabling neurological disorder, have not been analyzed in Asians by genome-wide association study (GWAS). Methods We conducted a two-stage case-control GWAS to identify susceptibility genes for migraine without aura in Han Chinese residing in Taiwan. In the discovery stage, we genotyped 1005 clinic-based Taiwanese migraine patients and 1053 population-based sex-matched controls using Axiom Genome-Wide CHB Array. In the replication stage, we genotyped 27 single-nucleotide polymorphisms with p < 10-4 in 1120 clinic-based migraine patients and 604 sex-matched normal controls by using Sequenom. Variants at LRP1, TRPM8, and PRDM, which have been replicated in Caucasians, were also genotyped. Results We identified a novel susceptibility locus (rs655484 in DLG2) that reached GWAS significance level for migraine risk in Han Chinese ( p = 1.45 × 10-12, odds ratio [OR] = 2.42), and also another locus (rs3781545in GFRA1) with suggestive significance ( p = 1.27 × 10-7, OR = 1.38). In addition, we observed positive association signals with a similar trend to the associations identified in Caucasian GWASs for rs10166942 in TRPM8 (OR = 1.33, 95% confidence interval [CI] = 1.14-1.54, Ppermutation = 9.99 × 10-5; risk allele: T) and rs1172113 in LRP1 (OR = 1.23, 95% CI = 1.04-1.45, Ppermutation = 2.9 × 10-2; risk allele: T). Conclusion The present study is the first migraine GWAS conducted in Han-Chinese and Asians. The newly identified susceptibility genes have potential implications in migraine pathogenesis. DLG2 is involved in glutamatergic neurotransmission, and GFRA1 encodes GDNF receptors that are abundant in CGRP-containing trigeminal neurons. Furthermore, positive association signals for TRPM8 and LRP1 suggest the possibility for common genetic contributions across ethnicities.
Collapse
Affiliation(s)
- Shih-Pin Chen
- 1 Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.,2 Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,3 Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Jong-Ling Fuh
- 1 Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.,2 Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Ming-Yi Chung
- 4 Department of Life Sciences & Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.,5 Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Ying-Chao Lin
- 6 Institute of Biomedical Sciences, Academia Sinica, Taiwan
| | - Yi-Chu Liao
- 1 Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.,2 Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Yen-Feng Wang
- 1 Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.,2 Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Chia-Lin Hsu
- 6 Institute of Biomedical Sciences, Academia Sinica, Taiwan
| | - Ueng-Cheng Yang
- 7 Institute of Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan
| | - Ming-Wei Lin
- 8 Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
| | - Jen-Jie Chiou
- 7 Institute of Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan
| | - Po-Jen Wang
- 9 Living Water Neurological Clinic, Tainan, Taiwan
| | - Ping-Kun Chen
- 10 Department of Neurology, Lin-Shin Hospital, Taichung, Taiwan
| | - Pi-Chuan Fan
- 11 Departments of Pediatrics, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Jer-Yuan Wu
- 6 Institute of Biomedical Sciences, Academia Sinica, Taiwan
| | | | - Lung-Sen Kao
- 4 Department of Life Sciences & Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | | | - Shuu-Jiun Wang
- 1 Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.,2 Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,12 Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| |
Collapse
|
2
|
Masliukov PM, Korzina MB, Porseva VV, Bystrova EY, Nozdrachev AD. Age-dependent changes in the neurochemical properties of sensory neurons. ADVANCES IN GERONTOLOGY 2014. [DOI: 10.1134/s2079057014030047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
3
|
Characterization of neuronal populations in the human trigeminal ganglion and their association with latent herpes simplex virus-1 infection. PLoS One 2013; 8:e83603. [PMID: 24367603 PMCID: PMC3868591 DOI: 10.1371/journal.pone.0083603] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 11/06/2013] [Indexed: 12/15/2022] Open
Abstract
Following primary infection Herpes simplex virus-1 (HSV-1) establishes lifelong latency in the neurons of human sensory ganglia. Upon reactivation HSV-1 can cause neurological diseases such as facial palsy, vestibular neuritis or encephalitis. Certain populations of sensory neurons have been shown to be more susceptible to latent infection in the animal model, but this has not been addressed in human tissue. In the present study, trigeminal ganglion (TG) neurons expressing six neuronal marker proteins were characterized, based on staining with antibodies against the GDNF family ligand receptor Ret, the high-affinity nerve growth factor receptor TrkA, neuronal nitric oxide synthase (nNOS), the antibody RT97 against 200kDa neurofilament, calcitonin gene-related peptide and peripherin. The frequencies of marker-positive neurons and their average neuronal sizes were assessed, with TrkA-positive (61.82%) neurons being the most abundant, and Ret-positive (26.93%) the least prevalent. Neurons positive with the antibody RT97 (1253 µm2) were the largest, and those stained against peripherin (884 µm2) were the smallest. Dual immunofluorescence revealed at least a 4.5% overlap for every tested marker combination, with overlap for the combinations TrkA/Ret, TrkA/RT97 and Ret/nNOS lower, and the overlap between Ret/CGRP being higher than would be expected by chance. With respect to latent HSV-1 infection, latency associated transcripts (LAT) were detected using in situ hybridization (ISH) in neurons expressing each of the marker proteins. In contrast to the mouse model, co-localization with neuronal markers Ret or CGRP mirrored the magnitude of these neuron populations, whereas for the other four neuronal markers fewer marker-positive cells were also LAT-ISH+. Ret and CGRP are both known to label neurons related to pain signaling.
Collapse
|
4
|
Takeda M, Takahashi M, Hara N, Matsumoto S. Glial cell line-derived neurotrophic factor modulates the excitability of nociceptive trigeminal ganglion neurons via a paracrine mechanism following inflammation. Brain Behav Immun 2013; 28:100-7. [PMID: 23131757 DOI: 10.1016/j.bbi.2012.10.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 10/29/2012] [Indexed: 01/05/2023] Open
Abstract
Previous our report indicated that acute application of glial cell line-derived neurotrophic factor (GDNF) enhances the neuronal excitability of adult rat small-diameter trigeminal ganglion (TRG) neurons, which innervate the facial skin in the absence of neuropathic and inflammatory conditions. This study investigated whether under in vivo conditions, GDNF modulates the excitability of nociceptive Aδ-TRG neurons innervating the facial skin via a paracrine mechanism following inflammation. We used extracellular electrophysiological recording with multibarrel-electrodes in this study. Spontaneous Aδ-TRG neuronal activity was induced in control rats after iontophoretic application of GDNF into the trigeminal ganglia (TRGs). Noxious and non-noxious mechanical stimuli evoked Aδ-TRG neuronal firing rate were significantly increased by iontophoretic application of GDNF. The mean mechanical threshold of nociceptive TRG neurons was significantly decreased by GDNF application. The increased discharge frequency and decreased mechanical threshold induced by GDNF were antagonized by application of the protein tyrosine kinase inhibitor, K252b. The number of Aδ-TRG neurons with spontaneous firings and their firing rates in rats with inflammation induced by Complete Freund's Adjuvant were significantly higher than control rats. The firing rates of Aδ-TRG spontaneous neuronal activity were significantly decreased by iontophoretic application of K252b in inflamed rats. K252b also inhibited Aδ-TRG neuron activity evoked by mechanical stimulation in inflamed rats. These results suggest that in vivo GDNF enhances the excitability of nociceptive Aδ-TRG neurons via a paracrine mechanism within TRGs following inflammation. GDNF paracrine mechanism could be important as a therapeutic target for trigeminal inflammatory hyperalgesia.
Collapse
Affiliation(s)
- Mamoru Takeda
- Department of Physiology, School of Life Dentistry at Tokyo, Nippon Dental University, 1-9-20, Fujimi-cho, Chiyoda-ku, Tokyo 102-8159, Japan.
| | | | | | | |
Collapse
|
5
|
Lucini C, D’Angelo L, Patruno M, Mascarello F, de Girolamo P, Castaldo L. GDNF family ligand RET receptor in the brain of adult zebrafish. Neurosci Lett 2011; 502:214-8. [DOI: 10.1016/j.neulet.2011.07.047] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 07/22/2011] [Accepted: 07/26/2011] [Indexed: 10/17/2022]
|
6
|
Takeda M, Tsuboi Y, Kitagawa J, Nakagawa K, Iwata K, Matsumoto S. Potassium channels as a potential therapeutic target for trigeminal neuropathic and inflammatory pain. Mol Pain 2011; 7:5. [PMID: 21219657 PMCID: PMC3024960 DOI: 10.1186/1744-8069-7-5] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 01/10/2011] [Indexed: 01/14/2023] Open
Abstract
Previous studies in several different trigeminal nerve injury/inflammation models indicated that the hyperexcitability of primary afferent neurons contributes to the pain pathway underlying mechanical allodynia. Although multiple types of voltage-gated ion channels are associated with neuronal hyperexcitability, voltage-gated K+ channels (Kv) are one of the important physiological regulators of membrane potentials in excitable tissues, including nociceptive sensory neurons. Since the opening of K+ channels leads to hyperpolarization of cell membrane and a consequent decrease in cell excitability, several Kv channels have been proposed as potential target candidates for pain therapy. In this review, we focus on common changes measured in the Kv channels of several different trigeminal neuropathic/inflammatory pain animal models, particularly the relationship between changes in Kv channels and the excitability of trigeminal ganglion (TRG) neurons. We also discuss the potential of Kv channel openers as therapeutic agents for trigeminal neuropathic/inflammatory pain, such as mechanical allodynia.
Collapse
Affiliation(s)
- Mamoru Takeda
- Department of Physiology, School of Life Dentistry at Tokyo, Nippon Dental University, 1-9-20 Fujimi-cho, Chiyoda-ku, Tokyo, Japan.
| | | | | | | | | | | |
Collapse
|
7
|
Lucini C, Carla L, Facello B, Bruna F, Maruccio L, Lucianna M, Langellotto F, Fernanda L, Sordino P, Paolo S, Castaldo L, Luciana C. Distribution of glial cell line-derived neurotrophic factor receptor alpha-1 in the brain of adult zebrafish. J Anat 2010; 217:174-85. [PMID: 20572899 DOI: 10.1111/j.1469-7580.2010.01254.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is a potent trophic factor for several types of neurons in the central and peripheral nervous systems. The biological activity of GDNF is mediated by a multicomponent receptor complex that includes a common transmembrane signaling component (the rearranged during transfection (RET) proto-oncogene product, a tyrosine kinase receptor) as well as a GDNF family receptor alpha (GFRalpha) subunit, a high-affinity glycosyl phosphatidylinositol (GPI)-linked binding element. Among the four known GFRalpha subunits, GFRalpha1 preferentially binds to GDNF. In zebrafish (Danio rerio) embryos, the expression of the GFRalpha1a and GFRalpha1b genes has been shown in primary motor neurons, the kidney, and the enteric nervous system. To examine the activity of GFRalpha in the adult brain of a lower vertebrate, we have investigated the localization of GFRalpha1a and GFRalpha1b mRNA and the GFRalpha1 protein in zebrafish. GFRalpha1a and GFRalpha1b transcripts were observed in brain extracts by reverse transcription-polymerase chain reaction. Whole-mount in-situ hybridization experiments revealed a wide distribution of GFRalpha1a and GFRalpha1b mRNAs in various regions of the adult zebrafish brain. These included the olfactory bulbs, dorsal and ventral telencephalic area (telencephalon), preoptic area, dorsal and ventral thalamus, posterior tuberculum and hypothalamus (diencephalon), optic tectum (mesencephalon), cerebellum, and medulla oblongata (rhombencephalon). Finally, expression patterns of the GFRalpha1 protein, detected immunohistochemically, correlated well with the mRNA expression and provided further insights into translational activity at the neuroanatomical level. In conclusion, the current study demonstrated that the presence of GFRalpha1 persists beyond the embryonic development of the zebrafish brain and, together with the GDNF ligand, is probably implicated in the brain physiology of an adult teleost fish.
Collapse
Affiliation(s)
- Carla Lucini
- Department of Biological Structures, Functions and Technology, University of Naples 'Federico II', Naples, Italy.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Takeda M, Kitagawa J, Nasu M, Takahashi M, Iwata K, Matsumoto S. Glial cell line-derived neurotrophic factor acutely modulates the excitability of rat small-diameter trigeminal ganglion neurons innervating facial skin. Brain Behav Immun 2010; 24:72-82. [PMID: 19679180 DOI: 10.1016/j.bbi.2009.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 07/14/2009] [Accepted: 08/05/2009] [Indexed: 12/31/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) plays an important role in adult sensory neuron function. However, the acute effects of GDNF on primary sensory neuron excitability remain to be elucidated. The aim of the present study was to investigate whether GDNF acutely modulates the excitability of adult rat trigeminal ganglion (TRG) neurons that innervate the facial skin by using perforated-patch clamping, retrograde-labeling and immunohistochemistry techniques. Fluorogold (FG) retrograde labeling was used to identify the TRG neurons innervating the facial skin. The FG-labeled small- and medium-diameter GDNF immunoreactive TRG neurons, and most of these neurons also expressed the GDNF family receptor alpha-1 (GFRalpha-1). In whole-cell voltage-clamp mode, GDNF application significantly inhibited voltage-gated K(+) transient (I(A)) and sustained (I(K)) currents in most dissociated FG-labeled small-diameter TRG neurons. This effect was concentration-dependent and was abolished by co-application of the protein tyrosine kinase inhibitor, K252b. Under current-clamp conditions, the repetitive firing during a depolarizing pulse were significantly increased by GDNF application. GDNF application also increased the duration of the repolarization phase and decreased the duration of the depolarization phase of the action potential, and these characteristic effects were also abolished by co-application of K252b. These results suggest that acute application of GDNF enhances the neuronal excitability of adult rat small-diameter TRG neurons innervating the facial skin, via activation of GDNF-induced intracellular signaling pathway. We therefore conclude that a local release of GDNF from TRG neuronal soma and/or nerve terminals may regulate normal sensory function, including nociception.
Collapse
Affiliation(s)
- Mamoru Takeda
- Department of Physiology, School of Life Dentistry at Tokyo, Nippon Dental University, 1-9-20, Fujimi-cho, Chiyoda-ku, Tokyo 102-8159, Japan.
| | | | | | | | | | | |
Collapse
|
9
|
Lazarov NE. Neurobiology of orofacial proprioception. ACTA ACUST UNITED AC 2007; 56:362-83. [PMID: 17915334 DOI: 10.1016/j.brainresrev.2007.08.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 08/22/2007] [Indexed: 12/29/2022]
Abstract
Primary sensory fibers innervating the head region derive from neurons of both the trigeminal ganglion (TG) and mesencephalic trigeminal nucleus (MTN). The trigeminal primary proprioceptors have their cell bodies in the MTN. Unlike the TG cells, MTN neuronal somata are centrally located within the brainstem and receive synaptic inputs that potentially modify their output. They are a crucial component of the neural circuitry responsible for the generation and control of oromotor activities. Gaining an insight into the chemical neuroanatomy of the MTN is, therefore, of fundamental importance for the understanding of neurobiology of the head proprioceptive system. This paper summarizes the recent advances in our knowledge of pre- and postsynaptic mechanisms related to orofacial proprioceptive signaling in mammals. It first briefly describes the neuroanatomy of the MTN, which is involved in the processing of proprioceptive information from the face and oral cavity, and then focuses on its neurochemistry. In order to solve the puzzle of the chemical coding of the mammalian MTN, we review the expression of classical neurotransmitters and their receptors in mesencephalic trigeminal neurons. Furthermore, we discuss the relationship of neuropeptides and their corresponding receptors in relaying of masticatory proprioception and also refer to the interactions with other atypical neuromessengers and neurotrophic factors. In extension of previous inferences, we provide conclusive evidence that the levels of transmitters vary according to the environmental conditions thus implying the neuroplasticity of mesencephalic trigeminal neurons. Finally, we have also tried to give an integrated functional account of the MTN neurochemical profiles.
Collapse
Affiliation(s)
- Nikolai E Lazarov
- Department of Anatomy and Histology, Faculty of Medicine, Medical University-Sofia, 2, Zdrave Street, BG-1431 Sofia, Bulgaria.
| |
Collapse
|
10
|
Quartu M, Serra MP, Boi M, Ferretti MT, Lai ML, Del Fiacco M. Tissue distribution of Ret, GFRalpha-1, GFRalpha-2 and GFRalpha-3 receptors in the human brainstem at fetal, neonatal and adult age. Brain Res 2007; 1173:36-52. [PMID: 17825269 DOI: 10.1016/j.brainres.2007.07.064] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 07/28/2007] [Accepted: 07/30/2007] [Indexed: 11/30/2022]
Abstract
Occurrence and localization of receptor components of the glial cell line-derived neurotrophic factor (GDNF) family ligands, the Ret receptor tyrosine kinase and the GDNF family receptor (GFR) alpha-1 to -3, were examined by immunohistochemistry in the normal human brainstem at fetal, neonatal, and adult age. Immunoreactive elements were detectable at all examined ages with uneven distribution and consistent pattern for each receptor. As a rule, the GFRalpha-1 and GFRalpha-2 antisera produced the most abundant and diffuse tissue labelling. Immunoreactive perikarya were observed within sensory and motor nuclei of cranial nerves, dorsal column nuclei, olivary nuclear complex, reticular formation, pontine nuclei, locus caeruleus, raphe nuclei, substantia nigra, and quadrigeminal plate. Nerve fibers occurred within gracile and cuneate fasciculi, trigeminal spinal tract and nucleus, facial, trigeminal, vestibular and oculomotor nerves, solitary tract, medial longitudinal fasciculus, medial lemniscus, and inferior and superior cerebellar peduncles. Occasionally, glial cells were stained. Age changes were appreciable in the distribution pattern of each receptor. On the whole, in the grey matter, labelled perikarya were more frequently observed in pre- and perinatal than in adult specimens; on the other hand, in discrete regions, nerve fibers and terminals were abundant and showed a plexiform arrangement only in adult tissue; finally, distinct fiber systems in the white matter were immunolabelled only at pre- and perinatal ages. The results obtained suggest the involvement of Ret and GFRalpha receptors signalling in processes subserving both the organization of discrete brainstem neuronal systems during development and their functional activity and maintenance in adult life.
Collapse
Affiliation(s)
- Marina Quartu
- Department of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy
| | | | | | | | | | | |
Collapse
|
11
|
Quartu M, Serra MP, Boi M, Sestu N, Lai ML, Del Fiacco M. Tissue distribution of neurturin, persephin and artemin in the human brainstem at fetal, neonatal and adult age. Brain Res 2007; 1143:102-15. [PMID: 17316574 DOI: 10.1016/j.brainres.2007.01.065] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 01/16/2007] [Accepted: 01/17/2007] [Indexed: 11/19/2022]
Abstract
The occurrence of the glial cell line-derived neurotrophic factor (GDNF) family ligands neurturin (NTN), persephin (PSP), and artemin (ART) was examined by immunohistochemistry in the normal human brainstem at pre-, perinatal and adult age. Immunolabelled neurons were unevenly distributed and each trophin had a consistent distribution pattern. As a rule, the NTN antiserum produced the most abundant and diffuse tissue labelling, whereas the lowest density of positive elements was observed after ART immunostaining. Labelling for NTN, PSP, and ART occurred at all examined ages. For each trophin, neuronal perikarya were observed within sensory and motor nuclei of cranial nerves, dorsal column nuclei, olivary nuclear complex, reticular formation, pontine nuclei, locus caeruleus, raphe nuclei, substantia nigra, and quadrigeminal plate. Nerve fibers occurred within gracile and cuneate fasciculi, trigeminal spinal tract and nucleus, oculomotor and facial nerves, solitary tract, vestibular nerve, medial longitudinal fasciculus, medial and lateral lemnisci, and inferior and superior cerebellar peduncles. Age changes were detected in the distribution pattern for each trophin. On the whole, in the grey matter, labelled perikarya were more frequently observed in pre- and perinatal than in adult specimens; on the other hand, in discrete regions, nerve fibers and terminals were abundant and showed a definite arrangement only in adult tissue; finally, distinct fiber systems in the white matter were immunolabelled only at pre- and perinatal ages. The results support the concept of a trophic involvement of NTN, PSP, and ART in the development, functional activity and maintenance of a variety of human brainstem neuronal systems.
Collapse
Affiliation(s)
- Marina Quartu
- Department of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy
| | | | | | | | | | | |
Collapse
|