Serotonin3 receptor stimulation in the nucleus tractus solitarii activates non-catecholaminergic neurons in the rat ventrolateral medulla
Autor: | Raul Laguzzi, Leni G.H. Bonagamba, J. C. Callera, Anne Nosjean, Michel Hamon, Benedito H. Machado |
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Přispěvatelé: | Neuropsychopharmacologie moléculaire, cellulaire et fonctionnelle, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM), Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP, Brazil |
Rok vydání: | 2002 |
Předmět: |
Male
[SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology Biguanides MESH: Rats Sprague-Dawley Urethane Rats Sprague-Dawley Catecholamines 0302 clinical medicine MESH: Animals MESH: Tyrosine 3-Monooxygenase Horseradish Peroxidase Catecholaminergic Medulla Oblongata 0303 health sciences MESH: Solitary Nucleus [SDV.NEU.PC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Psychology and behavior MESH: Proto-Oncogene Proteins c-fos Chemistry General Neuroscience [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences Rostral ventrolateral medulla MESH: Gene Expression Regulation Immunohistochemistry MESH: Serotonin Receptor Agonists Serotonin Receptor Agonists Chloralose MESH: Chloralose Medulla oblongata Brainstem Proto-Oncogene Proteins c-fos MESH: Receptors Serotonin medicine.medical_specialty MESH: Rats Tyrosine 3-Monooxygenase MESH: Receptors Serotonin 5-HT3 03 medical and health sciences MESH: Urethane MESH: Medulla Oblongata Internal medicine MESH: Catecholamines Solitary Nucleus medicine Animals MESH: Horseradish Peroxidase Medulla 030304 developmental biology Tyrosine hydroxylase Solitary nucleus MESH: Immunohistochemistry MESH: Biguanides MESH: Male Rats Endocrinology Gene Expression Regulation Receptors Serotonin Catecholaminergic cell groups Receptors Serotonin 5-HT3 030217 neurology & neurosurgery |
Zdroj: | Neuroscience Neuroscience, Elsevier-International Brain Research Organization, 2002, 112 (4), pp.935-949. ⟨10.1016/s0306-4522(02)00057-x⟩ Neuroscience, 2002, 112 (4), pp.935-949. ⟨10.1016/s0306-4522(02)00057-x⟩ |
ISSN: | 0306-4522 1873-7544 |
DOI: | 10.1016/s0306-4522(02)00057-x |
Popis: | International audience; The present study was performed to determine whether or not the increased arterial pressure triggered by 5-HT(3) receptor stimulation in the nucleus tractus solitarii and underlain by a sympathoexcitation is associated with the activation of ventromedullary cells known to be involved in vascular regulation, i.e. the C1 and A1 catecholaminergic cells. For this purpose, double immunohistochemical labeling for tyrosine hydroxylase and c-fos protein was performed all along the ventrolateral medulla after microinjection of 1-(m-chlorophenyl)-biguanide, a selective and potent 5-HT(3) receptor agonist, into the nucleus tractus solitarii of alpha-chloralose/urethane-anaesthetized rats. This treatment produced a significant elevation of arterial pressure ( approximately +35 mm Hg). Concomitantly, a significant increase in the number of c-fos expressing neurons was observed in the rostral ventrolateral medulla (+63%), in particular in its most anterior part (+78%), and in the medullary region surrounding the caudal part of the facial nucleus (+91%). Retrograde labeling with gold-horseradish peroxidase complex showed that at least some of these activated c-fos expressing cells project to the spinal cord. However, the number of double-stained neurons, i.e. c-fos and tyrosine hydroxylase positive neurons, did not increase at any level of the ventrolateral medulla. In contrast, under the same alpha-chloralose/urethane anesthesia, systemic infusion of sodium nitroprusside appeared to produce a hypotension and a marked increase in the density of such double c-fos and tyrosine hydroxylase expressing cells in the rostral ventrolateral medulla and the caudal medullary region surrounding the caudal part of the facial nucleus. These data indicate that medullary catecholaminergic C1 and A1 neurons are not involved in the pressor effect elicited by 5-HT(3) receptor stimulation in the nucleus tractus solitarii. However, this 5-HT(3) receptor-mediated effect is clearly associated with the excitation of (non-catecholaminergic) neurons within the pressor region of the ventral medulla. |
Databáze: | OpenAIRE |
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