Purkinje cell dendritic tree development in the absence of excitatory neurotransmission and of brain-derived neurotrophic factor in organotypic slice cultures.
The development of the dendritic tree of a neuron is a complex process which is thought to be regulated strongly by signals from afferent fibers. In particular the synaptic activity of afferent fibers and activity-dependent signaling by neurotrophic factors are thought to affect dendritic growth. We have studied Purkinje cell dendritic arbor development in organotypic cultures under suppression of glutamate-mediated excitatory neurotransmission, achieved with multiple combinations of blockers of glutamate receptors. Despite the presence of either single receptor blockers or combinations of blockers predicted to fully suppress glutamate-mediated excitatory neurotransmission Purkinje cell dendritic arbors developed similar to those of control cultures. Furthermore, Purkinje cell dendritic arbors in organotypic cultures from brain-derived neurotrophic factor (BDNF) knockout mice or after pharmacological blockade of trk-receptors also developed in a way similar to control cultures. Our results demonstrate that during the stage of rapid dendritic arbor growth signals from afferent fibers are of minor importance for Purkinje cell dendritic development because a seemingly normal Purkinje cell dendritic tree developed in the absence of excitatory neurotransmission and BDNF signaling. Our results suggest that many aspects of Purkinje cell dendritic development can be achieved by an intrinsic growth program.
Adcock
K H
KH
Anatomisches Institut, University of Basel, Switzerland.
Metzger
F
F
Kapfhammer
J P
JP
D000344:Afferent Pathways / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D019208:Brain-Derived Neurotrophic Factor / Q000172:deficiency / Q000235:genetics / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002525:Cerebellar Cortex / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D003712:Dendrites / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D018698:Glutamic Acid / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009924:Organ Culture Techniques; D011689:Purkinje Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D017470:Receptors, Glutamate / Q000187:drug effects / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*
D019208:Brain-Derived Neurotrophic Factor; D018691:Excitatory Amino Acid Antagonists; D017470:Receptors, Glutamate; D018698:Glutamic Acid; D020794:Receptor Protein-Tyrosine Kinases