Types of neurons of the claustrum in the rabbit - Nissl, Klüver-Barrera and Golgi studies

The studies were carried out on the claustrum of 8 adult rabbits. Four types of neurons were distinguished: 1. Multipolar neurons, which have dendritic trunks either with conus (multipolar polygonal perikarya) or without conus (multipolar rounded perikarya). Both subdivisions of the multipolar neurons have 3Œ6 dendritic trunks. Only some branches of these trunks have spines. An axon emerges mainly from the cell body, rarely from the initial part of the dendritic trunk. 2. Bipolar neurons with fusiform or rounded perikarya; they have two dendrites covered with spines. An axon originates directly from the cell body or from one of the dendritic trunks. 3. Triangular neurons, which have three dendritic branches with spines. An axon emerges directly from the soma, often near the primary dendritic trunk. 4. Pear-shaped neurons with one or two dendritic trunks arise from one pole of the cell body and with an axon that originates from the opposite side of the perikaryon. The dendrites are covered with spines

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 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 dorsal lateral geniculate nucleus in the guinea pig: Golgi and Klüver-Barrera studies

On the basis of Golgi and Klüver-Barrera preparations we have distinguished four types of neurons in the dorsal lateral geniculate nucleus of the guinea pig: 1. Fusiform neurons with 1-3 thick dendritic trunks arising from each pole of the soma. The dendritic trunks branch twice dichotomically. The branches sometimes show varicosities. 2. Pear-shaped cells. From one pole of the perikaryon one or two thick dendritic trunks arise, from the opposite pole an axon emerges. The ends of the dendritic branches divide in a tuft-like manner (a characteristic feature of the interneurons). 3. Rounded neurons with 4-7 dendritic trunks without cones. The dendritic trunks branch once or twice dichotomically and give finally 2-3 thin ramifications which show a varicose course and knob-like protuberances. 4. Triangular cells with 3 thick, conically arising dendritic trunks. They bifurcate dichotomically. The surface of the dendritic trunks and of their branches is smooth

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

Distribution and chemical coding pattern of somatostatin immunoreactivity in the dorsal striatum of the guinea pig

The present study provides a detailed description of somatostatin (SOM) distribution and the colocalization pattern of SOM, neuropeptide Y (NPY) and nitric oxide synthase (NOS) in the dorsal striatum (caudate-putamen complex) of the guinea pig. Within the dorsal striatum, SOM is found in a population of medium-sized aspiny interneurons. We found that 97% of all SOM-IR neurons expressed NPY simultaneously, while 98% of all NPY-ergic perikarya was simultaneously SOM-IR. On the other hand, while 98% of all SOM-IR cells were simultaneously NOS-IR, only 91% of all NOS-containing neurons exhibited SOM-immunoreactivity. Irrespective of their chemical coding, both types of SOM-IR neurons were scattered throughout the dorsal striatum, sometimes in the form of small, loosely arranged clusters of 2&#8211;4 cells. While SOM-IR and NPY-IR nerve fibers were present in all of the studied regions, they were more numerous in the ventro-medial part of the studied structure, with the exception of its caudal portion, where SOM-IR and NPY-IR fibers additionally formed a dense network in the part corresponding to the caudate nucleus. A low expression of staining for NOS-IR fibers was seen throughout the entire dorsal striatum. In some fibers, SOM and NPY were co-expressed. Fibers expressing both SOM and NOS were not found. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 690&#8211;699

Distribution and chemical coding pattern of the cocaine- and amphetamine-regulated transcript (CART) immunoreactivity in the preoptic area of the pig

This study provides a detailed description of cocaine-and amphetamine-regulated transcript (CART) distribution and the co-localization pattern of CART and gonadotropin releasing hormone (GnRH), somatostatin (SOM), neuropeptide Y (NPY), cholecystokinin (CCK), and substance P (SP) in the preoptic area (POA) of the domestic pig. The POA displays a low density of immunoreactive cells and rich immunoreactivity for CART in fibers. CART-immunoreactive (CART-IR) cell bodies were single and faintly stained, and located in the medial preoptic area (MPA) and the periventricular region of the POA. A high density of immunoreactive fibers was observed in the periventricular preoptic nucleus (PPN); a high to moderate density of fibers was observed in the MPA; but in the dorso-medial region of the MPA the highest density of fibers in the whole POA was observed. The lateral preoptic area (LPA) exhibited a less dense concentration of CART-immunoreactive fibers than the MPA. The median preoptic nucleus (MPN) showed moderate to low expression of staining fibers. In the present study, dual-labeling immunohistochemistry was used to show that CART-IR cell bodies do not contain any GnRH and SP. CART-positive fibers were identified in close apposition with GnRH neurons. This suggests that CART may influence GnRH secretion. Double staining revealed that CART-IR structures do not co-express any of the substances we studied, but a very small population of CART-IR fibers also contain SOM, CCK or SP. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 604&#8211;614

Types of neurons of the septal nuclei in the guinea pig: Golgi and Klüver-Barrera studies

Four types of neurons were distinguished in the septum of the guinea pig: 1. Piriform neurons (perikaryons 20&plusmn;25 &#956;m) with two thick dendritic trunks and an axon which emerges from the perikaryon on the opposite side to the dendritic trunks. These neurons are the main type of cells in the investigated nuclei; 2. Triangular neurons (24&plusmn;32 &#956;m) with three thick dendritic trunks arising conically from the perikaryons and a thin axon emerging directly from the soma; 3. Fusiform neurons (35&plusmn;40 &#956;m) which have two thick dendritic trunks on both poles of the cell body and a thin axon emerging from the soma; 4. Multipolar neurons (30&plusmn;35 &#956;m) with 4-5 thick dendritic trunks which emerge conically from the perikaryon. The axon arises near one of the dendritic trunks

The Effect of Cadmium on the Activity of Stress-Related Enzymes and the Ultrastructure of Pea Roots

The analysis of the effects of cadmium (Cd) on plant cells is crucial to understand defense mechanisms and adaptation strategies of plants against Cd toxicity. In this study, we examined stress-related enzyme activities after one and seven days of Cd application and the ultrastructure of roots of Pisum sativum L. after seven days of Cd treatment (10, 50, 100, and 200 &mu;M CdSO4). Our results showed that phenylalanine ammonia-lyase (PAL) activity and the amount of Cd accumulated in the roots were significantly positively correlated with the Cd concentration used in our experiment. However, Cd caused a decrease of all studied antioxidative enzyme activities (i.e., catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX)). The analysis of the ultrastructure (TEM) showed various responses to Cd, depending on Cd concentrations. In general, lower Cd concentrations (50 and 100 &mu;M CdSO4) mostly resulted in increased amounts of oil bodies, plastolysomes and the accumulation of starch granules in plastids. Meanwhile, roots treated with a higher concentration of Cd (200 &mu;M CdSO4) additionally triggered protective responses such as an increased deposition of suberin lamellae in the endodermal cell walls. This indicates that Cd induces a complex defense response in root tissues