RT Journal Article
SR Electronic
T1 Dopaminergic Co-Regulation of Locomotor Development and Motor Neuron Synaptogenesis is Uncoupled by Hypoxia in Zebrafish
JF eneuro
JO eNeuro
FD Society for Neuroscience
SP ENEURO.0355-19.2020
DO 10.1523/ENEURO.0355-19.2020
VO 7
IS 1
A1 Son, Jong-Hyun
A1 Stevenson, Tamara J.
A1 Bowles, Miranda D.
A1 Scholl, Erika A.
A1 Bonkowsky, Joshua L.
YR 2020
UL http://www.eneuro.org/content/7/1/ENEURO.0355-19.2020.abstract
AB Hypoxic injury to the developing human brain is a complication of premature birth and is associated with long-term impairments of motor function. Disruptions of axon and synaptic connectivity have been linked to developmental hypoxia, but the fundamental mechanisms impacting motor function from altered connectivity are poorly understood. We investigated the effects of hypoxia on locomotor development in zebrafish. We found that developmental hypoxia resulted in decreased spontaneous swimming behavior in larva, and that this motor impairment persisted into adulthood. In evaluation of the diencephalic dopaminergic neurons, which regulate early development of locomotion and constitute an evolutionarily conserved component of the vertebrate dopaminergic system, hypoxia caused a decrease in the number of synapses from the descending dopaminergic diencephalospinal tract (DDT) to spinal cord motor neurons. Moreover, dopamine signaling from the DDT was coupled jointly to motor neuron synaptogenesis and to locomotor development. Together, these results demonstrate the developmental processes regulating early locomotor development and a requirement for dopaminergic projections and motor neuron synaptogenesis. Our findings suggest new insights for understanding the mechanisms leading to motor disability from hypoxic injury of prematurity.