Neuronal population of the mesencephalon, rhombencephalon and spinal cord in zebrafish (Danio rerio)

Abstract

Anatomically central nervous system in zebra fish is represented by telencephalon, diencephalon, mesencephalon, mielencephalon and metencephalon. Histological study of neuronal population of mesencephalon, rombencephalon and spinal cord was made on 10 adult zebra fish, both sexes. Mesencephalon is the median vesicle of the brain having 3 main components: cerebral pedunculs, tegmentum and optic tectum. Tectum has seven layers of fibers and different celular composition. Rombencephalon comprise: cerebelum, ponce and medula oblongata and controls the autonomic functions and equilibrium. Cerebelum is composed by corpus cerebeli and valvula cerebeli, and together with ponce forms the metencephalon.Cerebelum have three layers of neurons: molecular, Purkinje cells and granular. Mielencephalon is represented by medulla oblongata, which is continuing caudally with the spinal cord, and is closing the 4th ventricle. Histologically, medula oblongata have small ovalar cells and small glial cells. In ventral spinal cord four domains are identified: p3, pMN, p1 and 0, composed from neurons having common features.