24 research outputs found
A comparative study of the mammalian amygdala: a Golgi study of the basolateral amygdala
The lateral (LA), basolateral (BL) and basomedial (BM) amygdaloid nuclei were
compared in the guinea pig (Cavia porcellus), rabbit (Oryctolagus cuniculus) fox
(Vulpes vulpes) and pig (Sus scrofa) by using the Golgi techniques. The interspecific
comparisons of the individual basolateral nuclei have shown that the neuronal
structure in each of them is extremely stable and remains almost unchanged
in the series of animals studied. The only difference is the size of the basolateral
neurons, which increases with the increasing size of the brain. Moreover, the
intraspecific comparisons revealed that in all the animals studied LA, BL and BM
form a fairly homogenous mass of cells in which similar cell types are present.
The most numerous neurons in all basolateral nuclei are the spiny cells that often
show a pyramidal or semi-pyramidal appearance (the Type I cells). Many of these
have conical cell bodies and easily recognisable "apical" and "basal" dendrites.
The Type II neurons are the most common variety of non-pyramidal cell and have
round cell bodies and smooth or sparsely spined dendrites. The axons of these
cells often form a dense terminal field that remains in the vicinity of the parent
soma. The Type III cells, which are only occasionally seen, are small spine-sparse
neurogliaform neurons with a few extremely delicate beaded dendrites and
a poorly branching local axon. These neurons were only located in LA and BL
The neuronal structure of the globus pallidus in the rabbit - Nissl and Golgi studies
The studies were carried out on the telencephalons of 12 adult rabbits. Two
types of neurons were distinguished: 1. Large neurons (perikarya 18–40 μm),
which have from 2 to 6 thick, long primary dendrites. Their perikarya have
a polygonal, triangular and fusiform shape. The large neurons in the centre of
GP have radiated dendritic trees, whereas the dendritic field of the cells along
the borders of GP has an elongated shape. The dendritic arbour is not homogeneous.
The dendrites may be covered with spindle-shaped dendritic swellings,
bead-like processes, not numerous spines or they may be smooth as well. The
dendritic branches form thin, beaded dendritic processes, that arise from any
part of the dendritic tree, as well as “complex terminal endings”, which have
various types of appendages on their terminal portions. An axon emerges from
a thick conical elongation either from the cell body or one of the dendritic trunks.
These neurons are the most numerous in the investigated material. 2. Small
nerve cells have been infrequent in our material. Their cell bodies are rounded or
polygonal. From the perikarya there arise 2–4 thin dendritic trunks, which may
have irregular swellings and few spines. The dendrites spread out in all directions,
making the dendritic field round or oval in shape. Generally most axons of
the small cells have not been impregnated. However, a few of them have a thin
axon with a conical elongation, which emerges from the cell body and bifurcates
into beaded processes
The types of neurones in the neostriatum of the guinea pig (Cavia porcellus): Golgi and Kl眉ver-Barrera studies
The Golgi technique stain was used to reveal the cellular structure of the neostriatum (nucleus caudatus and putamen) in the guinea pig. The computerised reconstructions were made from Golgi impregnated neurones. On the basis of various criteria, 4 types of neurones were distinguished in the guinea pig neostriatum:
1. The rounded neurones (most numerous) with 5–8 thin dendritic trunks;
2. The triangular nerve cells with 3 thick dendritic trunks;
3. Two types of multipolar neurones differing in dendritic arborisation pattern with 4–6 and 7–9 primary dendrites, respectively.
4. The pear-shaped cells, which divide into two distinctly different subpopulations
A morphometric study of the amygdala in the common shrew
The characteristic features of the common shrew amygdala (CA), as shown by
volumetric comparisons of the individual nuclei, are the poor development of
the lateral (LA) and basomedial (BM) nuclei as well as the particularly strong
formation of the basolateral (BL) and lateral olfactory tract (NLOT) nuclei. The
central (CE), cortical (CO) and medial (ME) nuclei are also well organised in this
species. All these features are even more distinctly visible when the total number
of neurons in the nuclei referred to are compared. A comparison of the
densities of neurons in the individual nuclei with the mean numerical density of
cells in the CA indicates that there are the 3 different regions within the common
shrew’s CA. The densities of neurons in the LA, BL, and BM are significantly
lower than the mean density of cells in the CA (p < 0.05). In the CE this value
does not differ from the mean (p > 0.05). In the CO, ME and NLOT the density
values are significantly higher than the mean (p < 0.05). Furthermore, a similar
division of the shrew’s CA can, to some extent, be performed using the size
parameters of the amygdaloid neurons as a marker. Interestingly, the large neurons
populate less densely organised CA areas like the LA, BL and BM, whereas
the small cells populate the ME and NLOT, where the neurons are densely arranged.
The CE and CO occupy intermediate positions, with the neurons similar
in size to the mean for the shrew’s CA
The neuronal structure of the inferior colliculus in the bank vole (Clethrionomys glareolus) - Golgi and Nissl studies
The inferior colliculus (IC) of the bank vole is made up of 3 nuclei: the external and
pericentral nucleus, which are located on the outer border of the IC, and the
central nucleus, which is the largest part of IC and shows a laminated structure.
On the basis of various morphological criteria 5 types of neurons have been distinguished
in the bank vole IC: 1. The rounded cells (perikarya 10-15 µm) with 2–4
primary dendritic trunks. The dendritic tree has a spindle-like shape. The axon
emerges from the soma or from the proximal portion of a dendrite. 2. The fusiform
neurons (17-20 µm) with 2 primary dendrites arising from both poles of the
perikaryon. The dendritic tree has the same shape as the previous type. The axon
originates from the proximal dendritic trunk. The rounded and fusiform cells constitute
the main neuronal type. 3. The pear-shaped neurons (10–13 µm) with 2
main stems or rarely 1. The axon emerges from the perikaryon or seldom from
the dendritic trunk. 4. The multipolar cells (18–23 µm), which have from 4 to 6
primary dendrites radiating in all directions. The dendritic tree has a spherical
shape. The axon emerges either from the proximal stem or directly from the
soma. 5. The triangular neurons (15–18 µm) with 3 primary dendritic trunks.
The axon originates from the perikaryon. The triangular cells are the least numerous.
All types of neurons in the bank vole IC bear spines and protrusions
The neuronal structure of the substantia nigra in the guinea pig: Nissl and Golgi study
The studies were carried out on the mesencephalons of adult guinea pigs. The preparations were made by means of the Golgi technique, as well as the Nissl and Kl眉ver-Barrera methods. Four types of neurons were distinguished in the substantia nigra (SN) of the guinea pig:
1. Bipolar neurons of two kinds: the neurons of the first kind have elongated, fusiform perikarya (25-40 µm), whereas the cells of the second kind have rounded and oval perikarya (15-22 µm). These neurons possess two dendritic trunks which arise from the opposite poles of the cell body and run for a relatively long distance. The bipolar neurons are the most numerous in the pars compacta of SN.
2. Triangular neurons with three primary dendrites arising conically from a perikaryon (20-35 µm). They are the most often observed type of neurons in the pars reticulata of SN.
3. Multipolar neurons with quadrangular or oval perikarya (22-35 µm) and 4-5 dendritic trunks which spread out in all directions.
4. Pear-shaped neurons (perikarya 15-25 µm), which have one or two primary dendritic trunks arising from one pole of the cell body. In all the types of neurons an axon originates either from the dendritic trunk or from the soma and is observed only in its initial segment
The neuronal structure of the medial geniculate body in the pig - Nissl and Golgi study
The studies were carried out on the brains of adult pigs. The preparations were
made by means of the Golgi technique as well as the Nissl and Kl眉ver-Barrera
methods. Four types of neurons were described in the medial geniculate body
(MGB) of the pig: 1. Multipolar neurons (perikarya 30–45 µm) with rounded, oval
or quadrangular perikarya from which arise 4-7 dendritic trunks. The dendrites
divide dichotomically twice, may send out collaterals and give off ramifications.
The dendritic branches possess varicosities and knob-like spines. These neurons
predominate in MGB. 2. Pear-shaped neurons (20-35 µm) with one or two dendritic
trunks arising from one pole of the cell body. These dendrites have a tufted
appearance. 3. Triangular neurons (30-45 µm) possess three thick dendrites which
first bifurcate near the soma and then divide profusely into daughter branches.
4. Fusiform neurons (30-50 µm) have usually two dendritic trunks which arise
from the opposite poles of the cell body and divide dichotomically twice. The
fusiform neurons are the least numerous in MGB. Most MGB neurons have on the
secondary tertiary dendrites and on their ramifications have delicate varicose or
bead-like appendages and spine-like protrusions. In all types of neurons an axon
arises either from the soma or from the initial portion of the dendritic trunk
Types of neurons of the subthalamic nucleus and zona incerta in the guinea pig — Nissl and Golgi study
The studies were carried out on the subthalamus of adult guinea pigs. Golgi impregnation, Nissl and Kl眉ver-Barrera methods were used for the study. In Nissl stained sections the subthalamic neuronal population consists of multipolar, fusiform, oval and pear-shaped perikarya. In two studied areas: nucleus subthalamicus (STN) and zona incerta (ZI) three types of neurons were distinguished.
Type I, multipolar neurons with quadrangular, triangular or oval perikarya. They have 3–6 primary dendrites wich run slightly wavy and spread out in all directions. Type II, bipolar neurons with fusiform or semilunar perikarya, they have two primary dendrites. Type III, pear-shaped neurons with 1–2 dendritic trunks arising from one pole of the neuron. In all types of neurons axon emerges from the perikaryon or initial segment of a dendritic trunk and can be followed at a maximum distance of about 50 μm