Purkinje-like cells of the rat cochlear nucleus: a combined functional and morphological study.
Purkinje-like cells (PLCs) of the cochlear nucleus (CN) are strongly calbindin positive neurones with unknown function. In the present work functional and morphological methods have been employed to provide data about PLCs in general, and about their possible involvement in the synaptic organisation of the CN in particular. PLCs had slightly elongated soma, from which a complex dendritic arborisation extended with highly variable dimensions. On the basis of their morphology, three classes of PLCs were identified. Positively identified PLCs fired a train of action potentials on sustained depolarization. When hyperpolarizing stimuli were applied, the presence of a slowly activating, ZD7288-sensitive inward current was noted that corresponded to the h-current. PLCs received both excitatory and inhibitory synaptic inputs. Functional experiments revealed that 76% and 14% of the spontaneous inhibitory postsynaptic currents recorded from the cell bodies of the PLCs were mediated via glycinergic and GABAergic synapses, respectively. PLCs presented strong cerebellin1-like immunoreactivity, but its distribution differed from that seen in cerebellar Purkinje cells. Our results indicate that PLCs are parts of the synaptic circuitry of the CN, thus they may be actively involved in the processing and analysis of auditory information.
Koszeghy
Aron
A
Department of Physiology, RCMM, Medical and Health Science Centre, University of Debrecen, P.O. Box 22, H-4012 Debrecen, Hungary.
Pál
Balázs
B
Pap
Pál
P
Pocsai
Krisztina
K
Nagy
Zsuzsanna
Z
Szucs
Géza
G
Rusznák
Zoltán
Z
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001306:Auditory Pathways / Q000166:cytology* / Q000378:metabolism*; D001307:Auditory Perception; D064026:Calbindins; D048430:Cell Shape / Q000502:physiology; D017626:Cochlear Nucleus / Q000166:cytology* / Q000378:metabolism*; D003712:Dendrites / Q000648:ultrastructure; D004558:Electric Stimulation; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D005455:Fluorescent Antibody Technique; D005968:Glutamate Decarboxylase / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D053444:Inhibitory Postsynaptic Potentials / Q000502:physiology; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D009924:Organ Culture Techniques; D018408:Patch-Clamp Techniques; D011689:Purkinje Cells / Q000166:cytology; D051381:Rats; D017208:Rats, Wistar; D064030:S100 Calcium Binding Protein G / Q000378:metabolism; D013194:Staining and Labeling; D009435:Synaptic Transmission / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D064026:Calbindins; D009419:Nerve Tissue Proteins; D064030:S100 Calcium Binding Protein G; D005680:gamma-Aminobutyric Acid; C046788:cerebellin; D005968:Glutamate Decarboxylase; D005998:Glycine