Ultrastructural studies of medullary synaptic inputs to vasopressin-immunoreactive neurons in the supraoptic nucleus of the rat hypothalamus.
Direct projections from the A1/C1 catecholaminergic cell group in the caudal ventrolateral medulla oblongata to neurons containing vasopressin (VP) in the supraoptic nucleus (SON) were studied electron microscopically by a double-labeling technique which combines anterograde tracing after injection of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) into the A1/C1 cell group with VP immunocytochemistry. WGA-HRP-labeled axon terminals originating from neurons in the A1/C1 cell group were found to make synaptic contacts with VP-immunoreactive cell bodies and dendrites in the SON, most often forming axo-dendritic synapses. This indicates that VP-containing neurosecretory neurons in the SON receive monosynaptic catecholaminergic input from the A1/C1 cell group.
Shioda
S
S
Department of Anatomy, Showa University School of Medicine, Tokyo, Japan.
Shimoda
Y
Y
Nakai
Y
Y
D000818:Animals; D001370:Axonal Transport; D001369:Axons / Q000648:ultrastructure; D003712:Dendrites / Q000648:ultrastructure; D006735:Horseradish Peroxidase; D008297:Male; D008526:Medulla Oblongata / Q000033:anatomy & histology / Q000502:physiology*; D016253:Microscopy, Immunoelectron; D009411:Nerve Endings / Q000648:ultrastructure; D009474:Neurons / Q000648:ultrastructure*; D051381:Rats; D017208:Rats, Wistar; D013495:Supraoptic Nucleus / Q000648:ultrastructure*; D013569:Synapses / Q000648:ultrastructure*; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis; D014667:Vasopressins / Q000032:analysis*; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D014909:Wheat Germ Agglutinins
D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D014909:Wheat Germ Agglutinins; D014667:Vasopressins; D006735:Horseradish Peroxidase; D014446:Tyrosine 3-Monooxygenase