RRC ID 4147
Author McLean DL, Fetcho JR.
Title Relationship of tyrosine hydroxylase and serotonin immunoreactivity to sensorimotor circuitry in larval zebrafish.
Journal J. Comp. Neurol.
Abstract Our previous study tracked the ontogeny of aminergic systems in zebrafish (Danio rerio). Here we use tyrosine hydroxylase (TH) and serotonin (5-hydroxytryptamine; 5-HT) immunoreactivity, in conjunction with retrograde and genetic labeling techniques, to provide a more refined examination of the potential synaptic contacts of aminergic systems. Our focus was on different levels of the sensorimotor circuit for escape, from sensory inputs, through identified descending pathways, to motor output. We observed 5-HT reactivity in close proximity to the collaterals of the Rohon-Beard sensory neurons in spinal cord. In the brainstem we found TH and 5-HT reactivity closely apposed to the dendritic processes of the nucleus of the medial longitudinal fascicle (nMLF), in addition to the ventral dendrites of the Mauthner neuron and its serial homologs MiD2cm and MiD3cm. Only TH reactivity was observed near the lateral dendrites of the Mauthner cell. TH and 5-HT reactivity were also positioned near the outputs of reticulospinal cells in spinal cord. Finally, both TH and 5-HT reactivity were detected close to the dendritic processes of primary and secondary spinal motor neurons. We also confirmed, using dual TH and 5-HT staining and retrograde labeling, that the sources of spinal aminergic reactivity include the posterior tuberculum (dopamine) and inferior raphe region (5-HT). Our data indicate that aminergic systems may interact at all levels of the sensorimotor pathways involved in escape. The identification of some of these likely sites of aminergic action will allow for directed studies of their functional roles using the powerful combination of techniques available in zebrafish.
Volume 480(1)
Pages 57-71
Published 2004-11-29
DOI 10.1002/cne.20281
PMID 15514919
MeSH Afferent Pathways / cytology Afferent Pathways / metabolism Animals Behavior, Animal / physiology Brain / cytology Brain / metabolism* Brain Stem / cytology Brain Stem / metabolism Catecholamines / metabolism* Dendrites / physiology Dendrites / ultrastructure Efferent Pathways / cytology Efferent Pathways / metabolism Fluorescent Dyes Immunohistochemistry Locomotion / physiology Microscopy, Confocal Neural Pathways / cytology Neural Pathways / metabolism* Presynaptic Terminals / metabolism Presynaptic Terminals / ultrastructure Raphe Nuclei / cytology Raphe Nuclei / metabolism Reticular Formation / cytology Reticular Formation / metabolism Serotonin / metabolism* Spinal Cord / cytology Spinal Cord / metabolism Synaptic Transmission / physiology Tyrosine 3-Monooxygenase / metabolism* Zebrafish / anatomy & histology Zebrafish / physiology*
IF 3.239
Times Cited 63
Zebrafish Islet-1 or HuC constructs