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Intracerebral haematoma was produced in 25 adult rats by infusion of 100 microl of autologous blood into the striatum. The animals' brains were removed at 1, 3, 7, 14 and 21 days after production of the haematoma. The TUNEL method was used to detect DNA fragmentation and TUNEL-positive cells were qualified. TUNEL-positive cells were already found on the first day of observation and were present for three weeks after haematoma production. These results provide evidence that programmed cell death is associated with intracerebral haemorrhage.

A total of 14 patients of various ages diagnosed with schizophrenia and, as an age-matched control group, 12 healthy subjects were examined using the MRI method of neuro-imaging. The volume of the following structures was evaluated in the right and left hemispheres: the superior temporal gyrus, the basolateral temporal area (the region including the middle temporal gyrus, inferior temporal gyrus and fusiform gyrus), the parahippocampal gyrus, the hippocampal head, the amygdaloid body and the inferior horn of the lateral ventricle. In schizophrenia a significant increase in the volume of the amygdaloid body on both the left and right sides was observed. In the patients, as in the control group, we noticed significant asymmetry between the left and right sides in the volume of the structures studied. The left amygdaloid body was significantly larger than the right, whereas the left hippocampal head and the temporal horn of the lateral ventricle were smaller than the right. Our findings suggest that in the early stages of schizophrenia, despite the increased volume of the amygdaloid body, the asymmetry between the structures of the temporal lobe is still present. However, the changes observed in the temporal lobe could be related to the functional disturbances observed in this disease.

Depression is one of the most common psychiatric disorders and is associated with considerable morbidity. In recent years structural-imaging technology has provided an opportunity to examine the brain anatomy in patients with the psychiatric illness. 10 patients of various ages and, as the control group, 16 healthy subjects were examined using the MRI method of neuroimaging. The volumes of the following structures were evaluated in the right and left hemispheres: the superior temporal gyrus, the basolateral temporal area (the region including middle temporal gyrus, inferior temporal gyrus and fusiform gyrus), the parahippocampal gyrus, the hippocampal head, the amygdaloid body and the lateral ventricle. The significant difference between the control group and the group with depression concerned the volume of the temporal horn of the lateral ventricle of both hemispheres. In depressed patients the left temporal horn was 49.8% and the right 38.4% larger in comparison with the control group. In the control group there were significant differences between the left and right hemispheres in the volume of all the structures studied, whereas in the group with depression these difference in volume between the hemispheres concerned only the amygdaloid body and the lateral ventricle.

The shape of the inferior horn of the lateral ventricle has been investigated in 100 (50 right and 50 left) human brain hemispheres which were fixed in 40% formaldehyde solution and cut frontally. It has been found that the shape of the inferior horn depends on the course and depth of the collateral and occipitotemporal sulci. In most cases a part from two main ventricular surfaces: the hippocampal and superolateral, there is one surface more, either the inferior-collateral eminence (Type I--97% of cases in the posterior part of the inferior horn, 49%--in the middle and 42%--in the anterior part) or the inferolateral, adjecent to the occipitotemporal sulcus (Type II--0%, 26% and 35%, respectively). In a few cases both collateral eminence and inferolateral surface were present (Type III--3%, 2% and 6% respectively). In type IV neither collateral eminence nor the inferolateral surface appeared (0%, 23%, 17% respectively). The authors suggest to designate the inferolateral surface, not mentioned in the literature, as the occpitotemporal eminence (of the inferior horn).

Data obtained by using ultrastructural and morphometric approaches revealed three types of neurons in the cat visual claustrum. The most numerous were medium-sized and large ones. They formed 3/4 of the cell population. The ultrastructural properties of those cell types were largely similar. Their cell bodies were oval, round, fusiform or triangular and contained more or less indented nuclear envelope. The cytoplasm of those cells was characterized by a high concentration of subcellular organelles and particularly rough endoplasmic reticulum. The characteristic feature of those cells was a low nucleus/cell body area ratio (47 +/- 1% and 43 +/- 1%, respectively). The proximal dendrites of medium-sized cells were usually wide at the base, relatively short and tapering, whereas, those arising in the large cells were often thick and had a short tapering base. The neurons described above stained by Golgi impregnation method showed spines on their distal dendrites both under the light and electron microscopy. The retrograde axonal transport of HRP and WGA-HRP following injections into the visual cortex confirm that they are mainly projection cells which form the ascending limb of the claustrocortical loop. The third type of neurons formed a less numerous group of small cells which differed from the larger ones in various respects. They possessed the large nuclei with deeply indented nuclear envelope and comparatively a thim layer of cytoplasm poor in subcellular organells among which free ribosomes and mitochondria were common. The nucleus/cells body area ratio high (59 +/- 2%). In Golgi preparations their dendrites did not show spines. The dendrites originating from that type of neurons were thin, long and did not posses a wide tapering base. They are mainly claustral intrinsic neurons.

The morphology of claustral neurons projecting to the motor, somatosensory, auditory and visual cortical areas in the rat was analyzed by means of combination of axonal retrograde transport and morphometric analysis. Fluoro-Gold (FG) injections placed into various cortical fields resulted in labeling in the claustrum four neuronal types: pyramidal with thick main dendrite, oval with a few thin dendrites spreading out in various directions, fusiform possessing two main dendrites arising from opposite poles of the cell body and polygonal. Pyramidal neurons prevailed in populations of neurons projecting to the motor cortex of the contralateral hemisphere. Oval neurons outnumbered other types in populations projecting to the somatosensory, auditory and visual cortical fields. The number of fusiform and polygonal neurons did not exceed at 12.5% together in any populations. Neurons projecting to the contralateral hemisphere were the largest claustral neurons (mean cross-section are 167.19 +/- 2.9 micron 2) whereas neurons projecting to the motor cortex where the largest claustral neurons projecting ipsilaterally (141.89 +/- 2.22 micron 2). There was no significant difference between neurons projecting to the somatosensory (113.46 +/- 1.9 micron 2) cortex and to the visual (111.8 +/- 1.4 micron 2) cortex whereas neurons related to the auditory are (95.98 +/- 1.75 micron 2) were the smallest claustral neurons. These observations pointed out that the morphology of claustral neurons is closely related to a cortical area to which they send axons.

The topography and cytoarchitectonics of the claustrum as well as morphometric parameters of its neurons were studied in 10 human brains obtained from patients without any detectable neuropathological changes. We distinguished four parts of the claustrum: dorsal, orbital, temporal and paraamygdalar. The dorsal and orbital parts contain larger cells, than those of the temporal and paraamygdalar parts, although these differences were statistically non significant. The highest neuronal density was observed in the paraamygdalar part. The nucleus and nucleus@cell body area ratio was significantly smaller in the dorsal part than in other parts of the claustrum. We described three types of neurons in the claustrum: (1) medium-sized either fusiform or triangular cells with darkly stained cytoplasm; they predominate in the dorsal and temporal parts, (2) medium-sized as well as large cells, either multipolar or pyramidal-like with lightly stained cytoplasm; they are most numerous in the orbital and paraamygdalar parts, (3) small, multipolar or oval neurons with darkly stained ring of cytoplasm; these types of neurons are uniformly distributed throughout all parts of the claustrum. The subdivision of the human claustrum is in accordance with our observations that each of these parts possesses connections with different cortical regions.

Cytoarchitectonics of the lateral tuberal nucleus--a phylogenetically new hypothalamic structure--was investigated using morphometric methods. The most characteristic feature of the human lateral tuberal nucleus is an extremely great variability of its shape and segmentation. The lateral tuberal nucleus consists mostly of several separated neuronal groups; in each brain the arrangement of these groups is different. In macaca the lateral tuberal nucleus is a single elongated neuronal structure much less variable than in man. The human LTN is approximately ten times larger than that in macaca, but the number of neurons is only about four times higher due to a lower neuronal density. The lateral tuberal nucleus both of man and macaca is a homogenous neuronal population with a very low coefficient of variability of cross-section neuronal area (30% and 24% respectively). The size of neuronal bodies in the lateral tuberal nucleus is about 42% smaller in macaca than in man. However, the size of neuronal nuclei is slightly (15%) bigger and the nucleus/cell body area ratio is about twice as high in macaca as that in man (40% and 21% respectively).

The parahippocampal (ventral) surface of the lateral part of the transverse fissure (LTF), formed by the parahippocampal gyrus, was examined in 53 human brain hemispheres without pathological changes. Cytoarchitectonics of this region was studied on the frontal histological sections stained either with cresyl violet or with Weil method. Four types of the shape of the parahippocampal surface of LTF were distinguished. In type 1 the surface is either flat or elevated in its medial part (medial eminence; 34.0%). In type 2 the surface is elevated in its lateral part (lateral eminence, 24.5%). In type 3 there are two eminences--the lateral and the medial; both of similar height (20.8%). In type 4 the lateral eminence is distinctly higher than the medial one (20.7%). The eminences contain cytoarchitectonically different structures. The lateral eminence is formed mainly by the subiculum and CA1 area, the medial by the presubicular region. The shape of the parahippocampal surface of LTF may be of importance in assessment of the Alzheimer's disease pathology.

Investigation of the dog's insular claustrum was performed using morphometric methods. The brains of 14 dogs (7-14 year-old) were studied. The size, shape and density of neurons are different in various parts of the insular claustrum. The posterior part, related to the visual system, is heterogenous and possesses medium-sized and small densely packed neurons, the average cross-sectional area of cell body being 175.8 +/- 45.5 micron2. The similar average cross-sectional area of cell body (174.1 +/- 55.3 micron2) was found in the central part of the insular claustrum. However, neuronal architecture is here less heterogenous and neurons are less densely arranged. The anterior part, connected mainly with the frontal and motor cortex, is more homogenous and contains loosely arranged neurons of a rather large size (average size--198.7 +/- 53.46 micron2).

The morphometric analysis of some hypothalamic nuclei was performed on 20 brains of subjects of both sexes aged from 29 to 79 years. They were divided into two groups: below and above the age of 60. Supraoptic (SON), lateral tuberal (LTN) and lateral mammillary (LMN) nuclei were investigated. In the group of aged subjects a decrease in cross-section area of neuron nuclei was observed in all investigated structures, expressed most in the LTN. A considerable increase in the neuron density with age was found in the LTN. The size of neuron cell bodies and the number of neurons did not change significantly with age in any of the investigated nuclei.

A dark type degeneration of axon terminals was observed in the dorsocaudal part of the claustrum following lesions of the visual cortex. Most of the degenerating axon terminals had synapses mainly with dendritic spines (64.1%) and small dendrites (25.1%). Only 5.8% of degenerating axon terminals formed synaptic contacts with medium-sized dendrites, 1.0% with large dendrites and 0.5%--with other parts of the claustral neurons. 3.5% of degenerating axon terminals were observed to form a contact with more than one postsynaptic structure. Degenerating axon terminals displayed synaptic contacts exclusively of asymmetrical type with clearly identifiable postsynaptic densities which suggest corticoclaustral afferents to be excitatory. Our data strongly support the notion that there are direct synaptic contacts between the ascending arm of the corticoclaustral neuronal loop.

The morphology of the claustrum in Galloway syndrome was investigated. Galloway syndrome is a rare autosomal recessive disease that causes microcephaly and is associated with kidney pathology. The brain examined was small, and the external surface of the hemispheres was lissencephalic, with an abnormal gyrification pattern. The whole cerebral cortex showed severe pathological changes, but the most affected area was the cortex lying on the medial aspect of the temporal lobe, especially the entorhinal cortex. In addition, the paraamygdalar and temporal parts of the claustrum were intensively changed. These results may confirm the opinion that the claustrum is a cortico-dependent structure and that the limbic cortex receives large projection from its ventral parts.

The cytoarchitectonics of the nucleus of the lateral olfactory tract (NLOT) was studied on Nissl stained sections in 6 brains of adult Wistar rats by using morphometric methods. The neuronal density of layer III (11,866 +/- 547 mm-3) is on average about three times smaller than that of layer II (30,947 +/- 1110 mm-3). The average cross-section area of neurons in layer III (254.3 +/- 3.8 microns2) is about twice as large as that of neurons in layer II (115.8 +/- 0.8 microns2). The layer II is rather homogenous in contrast to layer III which possesses neurons of various size. Other morphometric parameters of layer II and III are also different.