Sex differences of parvalbumin-immunoreactive neurons in the rat brain

During the last two decades numerous studies have proven the existence of sexual dimorphism in the brain of lower vertebrates, birds, and mammals. Differences between males and females have been found in various components of central nervous system (CNS), including volumes of certain nuclei, numbers of neurons and synaptic contacts, size of somata and outgrowths, as well as differences in neurotransmitter systems. The mechanisms by which these dimorphic features appear remain an open question for further elucidation. It is not clear yet how the morphological variations observed between sexes during development could be related to functional consequences in the adult organism.Biomedical Reviews 1997; 7: 91-96

Morphological changes in the wall of great saphenous vein after radiofrequency ablation

Radiofrequency ablation (RFA) is a relatively new method for endoluminal thermal occlusion of the incompetent saphenous veins. The aim of the present study was to investigate microscopically the changes in the venous wall after routine RFA procedures. Short pieces (n=7) from the knee segment of the great saphenous vein were taken during RFA procedures. The removed vein segments were immersion fixed in 10% formalin and proceed to routine histology examination. Microscopically, the venous wall after RFA showed circular disintegration of the intimal layer. In addition, cylindrical medial lesions with disintegration and intercellular splits and gaps were observed. No transmural thermal lesions were seen. The present results highlight the mechanism of predetermined tissue damage after RFA procedures of the great saphenous vein

Morphological changes in the rat aorta endothelium at the clamping sites

This study aimed to investigate on en face preparations the morphological changes in the rat aorta endothelium at the clamping sites while performing surgical anastomosis.Adult male Wistar rats (14-18-month-old, 390-420g) were used for the experiments. Under surgical anesthesia, the postrenal part of the abdominal aorta was dissected, clamped proximally and distally, cut and restored microsurgically using 10-0 suture. The clamping time was 30-40 min. At different days after surgery the animals were sacrificed, their aortas fixed and removed from the body and preparations for en face observation were made.En face preparations, obtained at the first postoperative day, showed complete denudation of the clamping sites. The most interesting endothelial cell population was noted at the borders of the clamping sites on the 3rd day after surgery - a large number of small endothelial cells and also few endothelial cells having very large size. At the later stages, the endothelial cell layer advanced rapidly to the denuded areas, as the complete restoration was observed after day 14

Neuromelanin-containing, catecholaminergic neurons in the human brain: ontogenetic aspects, development and aging

The present review compiles data on the development and aging ofneuromelanin (NM)-containing neurons in the central nervous system. Neuromelanin is brownish-to-black pigment that accumulates in the catecholaminergic (noradrenergic and dopaminergic) neurons and is a reliable natural marker that delineates the A1-A14 catecholaminergic groups of Dahlstrom and Fuxe in the human brain. The pigmentation of noradrenergic locus ceruleus neurons starts earlier than that of dopaminergic substantia nigra, but also a considerable individual variability is present. The pigmentation is well advanced in adolescence. The data at what age the maximal pigmentation is reached are controversial, as are the data on the cell loss in the NM-containing neuronal populations by normal aging. Thus, the participation ofNM in the pathogenesis of Parkinson`s disease remains enigmatic.Biomedical Reviews 2002; 13: 39-47

Age-related changes in the catecholaminergic neurons of the mesopontine tegmentum in the rat

Immunohistochemistry and computer assisted image analysis were used to examine the age-related changes in tyrosine hydroxylase- (TH-) immunoreactivity in substantia nigra (SN), ventral tegmental area (VTA), locus ceruleus (LC) and dopamine-betahyroxylase- (DBH-) immunoreactivity in LC and subceruleus nuclei of the rat. The findings in 3-month-old rats were compared with 28-month-old rats. In SN TH-positive neurons were concentrated in pars compacta and to a lesser extent - in pars lateralis. In VTA the TH-positive neurons were present over the entire area. In LC the immunoreactive perikarya were densely arranged and superimposed, but in subceruleus nuclei they were less numerous and individual cells were clearly discernible. The DBHimmunoreaction distinctly demonstrated the noradrenergic LC and subceruleus neurons. The results indicate of only subtle signs of cell loss in the dopaminergic neuronal population of SN and VTA, whilst the cell loss of the noradrenergic neurons in LC and subceruleus nuclei is evident. On the other hand, considerable age-related dendritic alterations were observed in all catecholaminergic nuclei. Cross-sectional area and optical density (OD) of the TH-immunoreactive neurons in SN, VTA and LC, and of the DBH-immunoreactive neurons in LC and subceruleus nuclei were investigated. In aging the cross-sectional area decreased statistically and OD of the neurons in SN decreased with 13%. In VTA the cross-sectional area did not change its dimensions, while the OD increased with 19%. In LC and subceruleus nuclei the cross-sectional area decreased with 36% and the OD of the neurons decreased with 16%. In conclusion, the most resistant to age-related changes catecholaminergic region in the rat is the VTA, followed by the pars compacta of SN. Rodent LC is a very vulnerable region.Biomedical Reviews 2007; 18: 45-58

Tarsal tunnel syndrome caused by anomalous muscle: case report

Accessory muscles within the tarsal tunnel have been reported as a rare cause of tarsal tunnel syndrome. The most common variation provoking this pathologic condition is the flexor digitorum accessorius longus muscle. Herein, we present a rare case of a patient with tarsal tunnel syndrome due to this muscular variation. The discussion of this case report can prompt foot and ankle surgeons to be more aware of this infrequent finding

Immunohistochemistry of synaptic proteins for synaptic exocytosis

The synaptic proteins synaptobrevin/VAMP, SNAP-25, Syntaxin1, NSF and α-SNAP were revealed by means of immunocytochemistry. Materials from the cerebral cortex of adult, newborn and postnatal rats (P6 and P11) were used. Immunostaining for synaptobrevin/VAMP was mainly around the synaptic vesicles, whereas the immunolabeling for SNAP-25 and syntaxin1 was revealed in most cases on the cytoplasmic surface of the presynaptic membrane and to a lesser extend - on synaptic vesicles. Immunostaning for NSF and α-SNAP was found out not only on the axoplasm of axonal endings and varicosities, but also in perikarya and dendrites. In the cerebral cortex of newborn rats, a small number of immunopositive presynaptic parts could be observed. The number of these immunolabeled structures increases evidently with increasing age of rats.Scripta Scientifica Medica 2013; 45(1): 29-34

Comparative electron microscopic and immunohistochemical study of stromal cells in giant cell tumor of bone

Giant cell tumor of bone is an osseous neoplasm that is histologically benign but clinically shows local aggression and high rate of recurrence. The histogenesis of this lesion remains unclear. The histological appearance does not predict the clinical outcome and there are still many unanswered questions with regard to both its treatment and prognosis. In order to further clarify this lesion, we examined ultrastructurally and immunohistochemically the tumor mononuclear cells in ten patients operated on in our hospital for matrix metalloproteinase-9. Positive reaction was detected in the spindle-like stromal cells of giant cell tumor of bone and these cells had the ultrastructural characteristics of fibroblastic cells. The other mononuclear cells did not express matrix metalloproteinase-9 and showed ultrastuctural characteristics of macrophage-like cells. The positive reaction for matrix metalloproteinase-9 in all patients clearly shows that this protease may play a key role in the pathophysiology of giant cell tumor of bone

CB1 receptors in the thalamic reticular nucleus during acute immobilization stress of the rat : an immunohistochemical study

Cannabinoids and opioids interact in a number of ways that could be therapeutically beneficial. The CB1 receptors are implicated with the endocannabinoid-mediated modulation of stress, pain, visceral sensation, synaptic plasticity in the thalamus via GABAergic signaling. Thalamic reticular nucleus (TRN) is a thin sheet of GABAergic neurons surrounding anterolateral surface of the thalamus. In our immunohistochemical study we demonstrated expression of CB1 immunoreactive neurons in a light microscope during a normal condition and after the acute stress in the rats. We found higher expression of CB 1 immunoreactivity in stressed animals compared with control group.Opioids and cannabinoids have been shown to have analgesic properties and they are considered as drug targets for the treatment of numerous neurological disorders, pain and stress

Immunohistochemical study on distribution of cannabinoid cb1 receptors in the rat`s prefrontal cortex after cold stress procedure

The prefrontal cortex (PFC), which mediates the emotional coping response to different stressful paradigms, is composed of distinct parts depends on stimulus involved physical or psychological stress. It also plays a role in a number of neurological conditions. It`s known that neuroendocrine control of homeostatic and reproductive functions including stress response and energy metabolism is fulfils by important signaling molecules as endogenous cannabinoids. The aim of the present study was to examine the effects of cold stress on distribution of CB1- receptors in PFC of rats. Immunohistochemical procedure for CB1-receptors was performed in adult male Wistar rats. The data were entered in the computer program, recorded automatically, calculated and compared by Student`s t-test. We found CB1-immunoreaction in axons and dendrites as well as in cell bodies where they presented as puncta on somata. The cells bodies were comprised of several distinct shapes: pyramidal, oval, fusiform and multipolar. Numerous fine-beaded fibers and puncta were seen on a handful of pyramidal large-sized neurons and many puncta were observed around the oval-shaped small- and medium-sized neurons.The PFC in cold stress rats demonstrated around 18% higher density of CB1-receptors compared with controls. In conclusion our results showed that cold stress exposure increased distribution of CB1-receptors in PFC of rats. These experimental data suggest that endocannabinoid system in this brain area may play an important role in the continuity of homeostasis in cold stress