Scanning and transmission electron microscope studies of the supraependymal neurons in the third ventricular wall of the Arctic lamprey, Lampetra japonica.
Scanning electron microscopy of the third ventricular wall of the arctic lamprey, Lampetra japonica, revealed the occurrence of supraependymal neurons in several regions of the ventricular surface. These neurons--as varicose fibers of various calibers--traversed among the cilia, microvilli, and bulbous protrusions of the ependymal surface. Occasionally synapse-like contact were found between these nerve fibers and the intraventricular processes of the cerebrospinal fluid (CSF)-contacting subependymal neurons in the hypothalamus. A possible function of the supraependymal neurons is discussed in relation to the hypothalamic neuroendocrine system.
D000818:Animals; D002552:Cerebral Ventricles / Q000033:anatomy & histology* / Q000648:ultrastructure; D005399:Fishes / Q000033:anatomy & histology*; D007798:Lampreys / Q000033:anatomy & histology*; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009474:Neurons / Q000033:anatomy & histology* / Q000648:ultrastructure