Differences in the NADPH-diaphorase positivity of the cholinergic brain stem neurons following damage of their thalamic termination field.

Following electrolesions of the anteroventral thalamic nucleus (the target structure for the NADPH-diaphorase positive axons of the cholinergic mesopontine cells, e.g. laterodorsal, pedunculopontine and lateral parabrachial nucleus) the intensity of NADPH-diaphorase staining changed drastically, but unlikely in each nucleus: it increased in the cells of the laterodorsal nucleus on the side of the lesion and decreased on the contralateral nucleus, whereas the staining intensity of the pedunculopontine and parabrachial cells remained unchanged bilaterally. In cases with small (partial) lesions of the anteroventral thalamic nucleus only lower number of heavily stained cells were observed in the laterodorsal nucleus ipsilateral to the thalamic lesion, whereas the number of slightly stained cells in the contralateral laterodorsal nucleus decreased. In contrast, not even large lesions of other thalamic nuclei, anterior or tuberal hypothalamus, zona incerta, pallidum internum, striatum or corpus callosum changed the symmetric intensity of the NADPH-diaphorase staining of the laterodorsal, pedunculopontine or lateral parabrachial nuclei. Increased intensity of the NADPH-diaphorase staining in the cells of the mamillary body was found two weeks after the electrolesions of the ipsilateral mamillo-thalamic tract or anteromedial thalamic nucleus. No degenerative changes or decrease of number of neurons in the laterodorsal tegmental nucleus in Nissl staining were detected after the electrolesions. Our data show that electrolytic lesions of target areas can lead to an upregulation of NOS expression in the parent cell bodies, provided that there is no wide collateralization as found for the pedunculopontine or parabrachial nuclei.

The effect of electrolytic thalamic lesions on the NADPH-diaphorase activity of neurons of the laterodorsal tegmental and pedunculopontine nuclei in rats.

Cholinergic neurons of the mesopontine complex have extensive ascending projections to the forebrain: the laterodorsal tegmental nucleus extensively innervates the anterior thalamus, the anteroventral nucleus in particular, whereas the pedunculopontine nucleus has widespread projections to both the thalamus and extrapyramidal structures. Most of their neurons express nitric oxide synthase (NOS) activity. Following electrolytic lesions of the anteroventral thalamic nucleus, nicotinamide adenine dinucleotide phosphate-diaphorase (NADPHd) activity in neurons of the laterodorsal tegmental nucleus changed drastically. The intensity of NADPH-diaphorase staining increased in laterodorsal tegmental neurons ipsilateral to the lesion side, but decreased contralaterally. The intensity of the NADPH-diaphorase staining of neurons of the pedunculopontine nucleus, however, remained unchanged bilaterally. After partial lesions of the anteroventral thalamic nucleus a similar effect was noted. In contrast, large electrolytic lesions involving other thalamic nuclei or extrapyramidal structures did not change the number of NADPH-diaphorase neurons or their intensity of staining in the laterodorsal tegmental nuclei. These data show that electrolytic lesions of target areas can lead to an upregulation of NOS expression in the parent cell bodies, provided that there is no wide collateralization as found for the pedunculopontine nucleus.

Experimental lesion of medial frontal cortex mediates inhibition of expression of carbohydrate-binding sites in the spleen macrophages in rat.

The fundamental concept of a neuroimmunological network is well appreciated although detailed description of the individual mechanisms has not yet been attained. In an effort to close this gap, the effect of electrolesion of the frontal medial cortex, a structure with the known "immunoreactivity", on selected phenotypic features of spleen macrophages was studied. Since sugar receptors (lectins) are pivotal for recognition, custom-made tools termed neoglycoproteins were employed to delineate any injury-induced changes of their expression. The total number of macrophages in the spleen red pulp was assessed using the ED-1 monoclonal antibody. The results showed that after lesion of the medial frontal cortex, the extent of expression of carbohydrate-binding sites in red pulp spleen macrophages significantly decreased without affecting the total number of these cells. These data intimate that distinct brain regions are involved in the control of the phenotype of macrophages in the central lymphoid organs by currently elusive biochemical mechanisms.

Brain lesion-induced alteration of selected phenotypic properties of spleen macrophages and their partial restoration in the course of foreign body reaction against intraperitoneally implanted polymers.

A lesion in the dorsoposterior part of the rat brain septum is known to exert an inhibitory effect on the delayed skin hypersensitivity and incorporation of radiolabeled thymidine into the lymphoid organs. To determine whether distinct properties of macrophages will also be modulated by this type of injury, we have focused upon the monitoring of expression of sugar receptors (lectins). In this study we show a reduction in the number of macrophages expressing carbohydrate-binding sites for asialoglycoproteins (beta-D-galactoside), alpha-D-mannoside and alpha-D-mannoside-6-phosphate in spleen macrophages after the lesion of the dorsoposterior septum of the brain in the rat. The number of ED-1+ macrophages was not influenced. The intraperitoneal injection of beads prepared from the copolymer of 2-hydroxyethyl methacrylate with dimethyl aminoethyl methacrylate (30 wt %) elevated significantly the number of ED-1+ spleen macrophages and number of macrophages with binding site(s) recognizing asialoglycoproteins and alpha-D-mannoside-6-phosphate, respectively. These results indicate that a foreign-body reaction appears to be able to mediate a phenotypic restoration of lectin expression by spleen macrophages altered by the brain lesion. It can be suggested that, for example, a probable production of cytokines by the inflammatory cells colonizing the implanted beads plays a role in this process.

The dorsal tegmentum of the pontomesencephalic junction of the rat--immunohistochemistry (choline acetyltransferase, tyrosine hydroxylase, substance P) and NADPH-diaphorase histochemistry in frontal and horizontal sections.

37 complete frontal and horizontal series of rat brain were studied to compare the distribution of choline acetyltransferase- (ChAT), tyrosine hydroxylase- (TH), substance P- (SP), calbindin D- (Calb) and NADPH-diaphorase (NADPH-d)-positive cells within the cytoarchitectonic borders of the latero-dorsal tegmental nucleus (L-D) and its neighbourhood. We found the same distribution, number and morphology of NADPH-d-positive cells and ChAT-positive cells. Rostrally, there are no borders between NADPH-d-positive cells of L-D and NADPH-d-positive cells of the lateral part of the dorsal raphe nucleus. Only a few TH-positive cells are intermingled with ChAT/NADPH-d-positive cells at the lateral border of L-D. TH-positive cells are larger or the same size as cholinergic neutrons. Locus coeruleus and its rostral part is full of TH-positive cells and their fibres run ventromedially towards L-D. Barrington's nucleus appears in double staining (ChAT and TH or NADPH-d and TH) as an empty area bordered by ChAT- or NADPH-d-positive cells of L-D and TH-positive fibres of the locus coeruleus. Some of these fibres run through the Barrington's nucleus. The shape and size of SP-positive neurons is the same as ChAT- and NADPH-d-positive neurons. SP-positive neurons are sparsely distributed in all parts of L-D, but there are only a few SP-positive cells in its medial part. About 50% of the ChAT- and NADPH-d-positive cells are also SP-positive. Results are expressed by figures in three representative frontal sections and one horizontal section through the dorsal mesopontine tegmentum.

Phospholipids and calcium alterations in platelets of schizophrenic patients.

Alterations in phospholipid metabolism in blood elements have been proposed as the possible biochemical marker of schizophrenia. In the present study, we investigated the composition and membrane distribution of phospholipids in platelets of drug-free schizophrenic patients and controls. We have demonstrated that platelets of drug-free schizophrenics have significantly higher cytosolic Ca2+ levels in comparison with healthy controls. Platelets of drug-free schizophrenic patients have a lower content of phosphatidylinositol (PI). After thrombin activation, PI is the target of phospholipase C instead of phosphatidylinositol 4,5-bisphosphate (PIP2), which is hydrolyzed in platelets of controls. Alterations in the distribution of phospholipids were found in the plasma membrane of platelets of schizophrenic patients. We suggest that alterations in phospholipid metabolism might be evoked by a disturbance of calcium homeostasis in schizophrenic patients.

[Phospholipase A2 in schizophrenia]. / Fosfolipáza A2 u schizofrenního onemocnení.

The objective of the present work was to evaluate on the basis of the authors' data and data in the literature the role of phospholipase A2 in the pathogenesis of schizophrenia. The authors submit available literature pertaining to the problem as well as their own experimental findings. Based on the submitted facts, it cannot be states that phospholipase A2 is a specific marker of schizophrenia.

Topographical organization of NADPH-diaphorase positive neurons and fibres in dorsal ponto-mesencephalic tegmentum in the rat brain.

20 complete series of the rat brain, stained with cresylviolet or with the NADPH-diaphorase positive neurons demonstration method were used to compare the topographical organization of the borders of the dorsal mesopontine tegmental nuclei (latero-dorsal tegmental nucleus, dorsal and ventral tegmental nuclei of Gudden, dorsal raphe nucleus and substantia grisea centralis pontis) and to describe in detail NADPH-d positive cells and fibres in this area. We have found that topography of the cells and the borders of the nuclei were similar by the both methods, but NADPH-d histochemistry has shown the extension of NADPH-d positive cells to neighbouring structures and we would divide some nuclei into independent parts (e.g., pars medialis, ventralis and rostralis of the laterodorsal tegmental nucleus). We discussed the possibility of the projection and configuration of NADPH-d positive fibres running from the mesopontine tegmentum to the diencephalon.

Effect of postmortem storage on the [3H]hemicholinium-3 binding site in the rat brain. Preliminary study for investigations of human patients with Alzheimer's disease.

The effect of postmortem storage at room temperature (24-26 degrees C, 0-4 h) and cold-room temperature (4 degrees C, (0-24 h) on the [(3)H]hemicholinium-3 binding sites in the brain hippocampus, cortex and cerebellum of 3-month-old Wistar rats was studied. A slow decrease in the density of the binding sites was observed at both temperatures, which was best fit by a linear model common for all three brain regions. No systematic alterations of the affinity of the binding sites for hemicholinium-3 were found. The values obtained from experiments with animals were compared with the values measured in the frontal cortex of old men. Approaches to the evaluation of data obtained from postmortem samples of human brain tissue of patients with Alzheimer's disease are proposed.

Changes in the configuration and the dimensions of the fossa hypophysealis in the rat (Rattus rattus norvegicus) dependent on the age, weight and individual size of the skull.

The aim of our work was to describe the fossa hypophysealis in the most common laboratory animal--in the rat, to measure its dimensions, to determine its stereotactic coordinates and to find the dependence of these coordinates on the age, weight and individual size of the skull in different rats. From this measurement we obtained data on the growth and possible shifts of the fossa hypophysealis but also found data facilitating the selection of animals to stereotactic operations so that the hit of the hypophysis be the most probable. There are suitable coordinates for bilaterally stereotactic intervention into the middle female rats hypophysis in conclusions of our work.