Premium
The development of the Purkinje cell in the cerebellar cortex of the opossum
Author(s) -
Laxson L. C.,
King J. S.
Publication year - 1983
Publication title -
journal of comparative neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.855
H-Index - 209
eISSN - 1096-9861
pISSN - 0021-9967
DOI - 10.1002/cne.902140307
Subject(s) - purkinje cell , cerebellar cortex , cerebellum , postsynaptic potential , neuroscience , dendritic spine , dendrite (mathematics) , biology , golgi apparatus , synaptic vesicle , anatomy , microbiology and biotechnology , vesicle , endoplasmic reticulum , hippocampal formation , biochemistry , genetics , receptor , geometry , mathematics , membrane
The development of the Purkinje cell in the cerebellar cortex of the opossum, Didelphis virginiana , was analyzed by using Golgi preparations and electron microscopy. The maturation process of the Purkinje cell was observed to occur in five stages: the immature stage, the perisomatic den‐drite stage, the perisomatic spine stage, the main dendrite stage, and the adult stage. These stages were first defined by Hendelman and Aggerwal (′80), using Golgi preparations of immature mouse cerebellum. Each of the five stages of Purkinje cell development, as observed in electron micrographs, is characterized by distinct synaptic relationships and cytological features. During the first or immature stage (postnatal (PN) 19‐32), the Purkinje cells have long apical processes which may be involved in the early migration of these neurons. Few boutons make synaptic contacts with Purkinje cells during the early part of this first stage; synapses are more frequent by the end of the immature stage. The second or perisomatic dendrite stage (PN 33‐44) is characterized by numerous somatic processes which have the cytological characteristics of dendrites. All synaptic contacts present during this stage form asymmetric contacts and contain round vesicles. The shape of the terminals and their postsynaptic location were used to tentatively distinguish different types of terminals. During the third or perisomatic spine stage (PN 45‐60) the Purkinje cell has numerous somatic spines and the dendritic tree is achieving its mature form. Most synaptic terminals observed during this period have asymmetric junctions and contain spherical vesicles; both the perisomatic spines and the dendritic shafts and spines are the postsynaptic sites of these terminals. Another type of bouton has pleomorphic vesicles and forms indistinct symmetric junctions directly on the cell body. The fourth stage, the main dendrite stage (PN 61‐77), is characterized by the loss of the perisomatic spines. Terminals on the soma contain pleomorphic vesicles and form symmetric synapses. The thorns of the primary and secondary dendrites and the more distal dendritic spines are postsynaptic to boutons with spherical vesicles and asymmetric junctions. The adult stage or the mature stage (PN 78‐adult) is characterized by the appearance of adult synaptic relationships. These data suggest that although olivary axons are present in the cerebellum by PN 14 (King et al., ′82), synaptogenesis does not ensue until the latter part of the immature stage (PN 26‐32). During the subsequent stages of Purkinje cell development, synaptic formation and remodeling proceeds until the adult structure and synaptic relationships are achieved about PN 78–80.