The types of neurones in the neostriatum of the guinea pig (Cavia porcellus): Golgi and Klüver-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 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

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&#8217;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&#8217;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&#8217;s CA

The neuronal structure of the red nucleus in newborn guinea pigs

The preparations, stained according to the Nissl and Klüver-Barrera methods, were used to describe the topography and morphology of the red nucleus (RN) as well as the structure of the rubral perikarya in newborn (P0) guinea pigs. The Golgi impregnated preparations were used to distinguish types of neurons. RN is a uniform cell group and has the length from 740 to 860 &micro;m. The Nissl stained perikarya were classified into three categories: big, medium-sized and small (A, B, C, respectively). The big perikarya, which contain a lot of tigroidal substance, were mainly observed at the caudal and ventral portions of RN. The small perikarya often have multiple nucleoli. The impregnated neurons were classified into 5 types: 1 - large, aspiny, rich-arborised multipolar cells, 2 - large and medium sized, spiny, rich-arborised fusiform or pear-shaped cells, 3 - medium-sized, spiny, rich-arborised rounded cells, 4 - medium-sized, spiny, richarborised bipolar cells, 5 - small and single medium-sized cells. The 5th type constitutes a heterogeneous population and also has neurons in different developmental stages. Intraspecies variations concerning both the length of RN and a number of the triangular perikarya of the red nucleus were observed in the examined guinea pigs

The cytoarchitectonic and neuronal structure of the red nucleus in guinea pig: Nissl and Golgi studies

The present studies were carried out on the brains of adult guinea pigs, Dunkin-Hartley strain. On the basis of preparations, they were stained according to the Nissl and the Klüver-Barrera method's; a short description of the cytoarchitectonics and the characteristics of the rubral cells were written. The red nucleus (RN) of the guinea pig is 1.2 mm in length. Three cellular parts in RN, and three classes (A, B, C) of the rubral cells were distinguished. Taking into consideration the predominant cell size, RN was divided into magnocellular part (RNm), parvocellular part (RNp) and intermediate part (RNi). On the basis of Golgi impregnated preparations four neuronal types (I, II, III, IV) were distinguished. To sum up, in the guinea pig were observed: the large, mainly multipolar (type I) and bipolar (type II) spiny being coarse (class A) in Nissl material; the medium-sized, triangular, aspiny (type III) corresponding to the fine cells (class B); and the small, both spiny and aspiny neurons (type IV), which are the fine or achromatic cells (classes B or C) in Nissl stained slices. The highest degree of dendritic branching was observed in type I, whereas the lowest in cells of types III and IV

A morphometric study of the preoptic area of the guinea pig

The aim of the study was to provide the topography and morphometric characteristics of the preoptic area (POA) of the guinea pig. The study was carried out on the brains of sexually mature guinea pigs of both sexes. A uniform procedure was followed in the study of the paraffin-embedded brain tissue blocks of males and females. The blocks were cut in the coronal plane into 50 mm sections and stained according to the Nissl method. The guinea pig POA consists of four parts: the medial preoptic area (MPA), lateral preoptic area (LPA), periventricular preoptic nucleus (PPN), and median preoptic nucleus (MPN). The topography and general structure of POA parts are similar in males and females. However, the PPNa cells of females are more intensely stained and are more densely packed than the PPNa cells of males. For morphometric analysis, the MPA and LPA as well as PPN and MPN were considered respectively as uniform structures, namely MPA-LPA and PPN-MPN. The statistical analysis showed that the volume of the PPN-MPN was larger in males than in females, whereas the MPA-LPA volume did not differ between the sexes. Moreover, the numerical density and the total number of neurons were statistically larger in males than in females in both the MPA-LPA and PPN-MPN. The parameters describing POA neurons were larger for MPA-LPA neurons in comparison with the PPN-MPN neurons. However, in this respect no sex differences were observed in both studied complexes. Folia Morphol 2010; 69, 1: 15-2

The neuronal structure of the dorsal nucleus of the lateral geniculate body in the common shrew (Sorex araneus) and the bank vole (Clethrionomys glareolus): Golgi and Nissl studies

The topography and neuronal structure of the dorsal nucleus of the lateral geniculate body (GLd) of the common shrew and the bank vole are similar. The lateral geniculate body of both the species examined has a homogeneous structure and no observable cytoarchitectonic lamination. On the basis of the shape of the dendritic arbours as well as the pattern of dendritic arborisations the following two types of neurons were distinguished. Type I &#8220;bushy&#8221; neurons that have multipolar or round perikarya (common shrew perikarya 9&#8211;12 &micro;m, bank vole perikarya 10&#8211;13 &micro;m), with 4&#8211;6 short thick dendritic trunks that subdivide into many bush-like branches. The dendritic trunks are smooth, in contrast to the distal branches, which are covered with numerous spine-like protrusions of different lengths and forms. An axon emerges from the soma, sometimes very close to one of the primary dendrites. The type I neurons are typically projection cells that send their axons to the primary visual cortex. These neurons predominate in the GLd of both species. Type II neurons, which have an elongated soma with primary dendrites arising from opposite poles of the perikaryon (common shrew perikarya 8&#8211;10 &micro;m, bank vole perikarya 9&#8211;11 &micro;m). The dendritic arbours of these cells are less extensive and their dendrites have fewer spines than those of the type I neurons. Axons were seldom observed. The type II neurons are presumably interneurons and are definitely less numerous than the type I neurons

A morphometric comparative study of the lateral geniculate body in selected placental mammals: the common shrew, the bank vole, the rabbit, and the fox

The lateral geniculate body (LGN) was morphometrically examined and compared in representatives of four mammalian orders (Insectivora, Rodentia, Lagomorpha, and Carnivora). In each studied species, the lateral geniculate body was divided into two distinct parts: the dorsal nucleus (LGNd) and the ventral nucleus (LGNv). The lateral geniculate body of the common shrew and the bank vole are very similar in appearance and nuclear pattern. The dorsal and ventral nuclei of these two species also have the most similar statistical characteristics. The lateral geniculate body of the fox has the most complicated morphology and multilayered structure. A significant disproportion was observed between the sizes of both geniculate nuclei in the fox, where the dorsal nucleus definitely surpassed the ventral nucleus in terms of volume. With the exception of the fox, the neuronal density of the LGN nuclei was negatively correlated with the volumes of the LGN. The mean neuronal size of the LGNd and LGNv, which was the resultant of the length, width, area, and circumference of the soma, grew correlatively to the volumes of these nuclei. In all examined species, somas of the LGNd neurons are distinctly larger and have more similar shapes than the LGNv perikarya. In addition, the numerical density of neurons in the ventral nucleus is significantly higher than in the dorsal nucleus. All these morphometric parameters clearly differentiate the LGNd from the LGNv

The neuronal structure of the preoptic area in the mole and the rabbit: Golgi and Nissl studies

The present studies were carried out on the brains of the adult mole and rabbit. The preparations were made by means of the Golgi technique and the Nissl method. Two types of neurons were distinguished in the preoptic area (POA) of both species: bipolar and multipolar. The bipolar neurons have oval, fusiform or round perikarya and two dendritic trunks arising from the opposite poles of the cell body. The dendrites bifurcate once or twice. The dendritic branches have swellings, single spine-like and filiform processes. The multipolar neurons usually have triangular and quadrangular perikarya and from 3 to 5 dendritic trunks. The dendrites of the mole neurons branch sparsely, whereas the dendrites of the rabbit neurons display 2 or 3 divisions. On the dendritic branches varicosities and different protuberances were observed. The general morphology of the bipolar and multipolar neurons is similar in the mammals studied, although the neurons of the rabbit POA display a more complicated structure. Their dendritic branches show more divisions and possess more swellings and different processes than the dendrites of the neurons of the mole POA. Furthermore, of the multipolar neurons only the dendrites in POA of the rabbit were observed to have a rosary-like beaded appearance

A morphometric study of the amygdala in the guinea pig

The characteristic features of guinea pig amygdala (CA), as shown by volumetric comparisons of the individual nuclei, are the poor development of the basolateral (BL) and lateral olfactory tract (NLOT) nuclei as well as the strong formation of the lateral (LA) and basomedial (BM) nuclei. The central (CE), cortical (CO) and medial (ME) nuclei also appear to be well represented in this species. All these features are even more pronounced when the total number of neurons in the nuclei referred to was taken into consideration. A comparison of the densities of neurons in the individual nuclei with the mean numerical density of cells in the guinea pig CA indicates that the densities of neurons in LA, BL, BM, CE and CO are significantly lower than the mean (p < 0.05), whereas in the ME and NLOT these values are significantly higher than the mean (p < 0.05). It is noteworthy, that the densities of the neurons in CE and CO do not differ statistically from each other (p > 0.05) and are significantly higher than the respective values in LA, BL and BM (p < 0.05). Furthermore, a similar division of the guinea pig CA may to some extent be made using the size parameters of the amygdaloid neurons as a marker. Interestingly, the large neurons populate organised CA areas like LA, BL and BM less densely, whereas the small cells create ME and NLOT, where the neurons are densely arranged. CE and CO occupy intermediate positions, with the neurons similar in size to the mean for the guinea pig CA