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Objectives: The aim of this study was to investigate the effects of pinealectomy and melatonin treatment on the rat thymus gland characteristics, taking into consideration possible gender differences., Materials and Methods: Thirty adult Wistar rats of both sexes were divided into three groups. Group C and group PX served as control groups and included sham-pinealectomized and pinealectomized animals that were treated with 10% ethanol solution (0,1ml/daily, subcutaneous). Animals from third group (group PXM) underwent pinealectomy and seven days after surgery started receiving melatonin dissolved in 10% ethanol solution (3mg/kg/daily, subcutaneous). All animals were treated for 4 weeks., Results: Volume density of the thymus cortex showed statistically significant (p<0,05) decrease while the volume density of the thymus medulla was increased in the pinealectomized compared to the sham-pinealectomized female rats. Numerical density of macrophages as well as the distribution of blood vessels showed no gender differences. The numerical density of lymphocytes was statistically significantly decreased in female in comparison to the male pinealectomized rats. Melatonin treatment was proved to cause reverse effects in the sense that the results from the melatonin treated group corresponded to the results obtained from the control group of animals., Conclusion: The results of this study suggest that the pinealectomy causes gender-related changes in the rat thymus. Short-term melatonin treatment showed reverse effect, equally in both sexes.

Seven days after the application of 2% lidocaine (4 ml doze, the speed of application 3 ml/min, mean application pressure 15 +/- 2.47 kPa) into mesoneurium of adult rabbit sciatic nerve, a nerve segment was intravitally excided from the injection site with a length of 1 cm and qualitatively and quantitatively analyzed. Histological changes at the level of total nerve structures were found, especially of its sheaths. Epi- and interfascicular epineurium were thickened with a hipercellularity of a mononuclear inflammatory process type. On the side of application, occasional delamination of perineurium was registered. Myelinated fibers were sporadically demyelinated, followed by axon degeneration which, in thick fibers, reached a full disintegration. In general, the damages were more severe at the side of application although some zonal differences in the degree of damage (above, below and at the site of application) within individual fasciculi were expressed. A significantly higher volume density of epifascicular and interfascicular connective tissue in comparison to the control, untreted nerves, observed by the stereological analysis, may be considered as an inflammatory-repairing reaction which we identified microscopically. At the same time, we found a significantly higher volume density of endoneurium in lidocaine treated nerves.

Pineal gland has and antistressogenic role. Its main hormone, melatonin, has radio protective effect on endocrine and other dynamic tissues. In our previous study, we have shown that pinealectomy changes the behavior of suprarenal gland in totally irradiated rats. The aim of this study is to evaluate the effect of exogenous melatonin on suprarenal gland of rats with or without pineal gland. Four months after pinealectomy (experimental group) or shampinealectomy (control group), adult Wistar male rats were daily treated with 0,2 mg of melatonin intraperitoneally, during two weeks. Thereafter, all animals were totally irradiated with 8 Gy of Gamma rays produced from Cobalt 60. Animals who survived were sacrificed on the 17(th) post irradiation day. Qualitative and quantitative characteristics of the suprarenal gland were studied using histological methods. The results show that exogenous melatonin had protective role on suprarenal gland in totally irradiated rats and that those effects were more pronounced in the presence of pineal gland.

Objectives: Pineal gland acts as a reley where an anabolic activity be replaced to catabolic and conversely, to adapt a biological rhythm according to the organisme requirement. It is established that pineal extracts stimulate lymphopoiesis in the lymph node and had a radioprotective effects in lymph tissues. Lymph nodes reaction was investigated four weeks after pinealectomy, using qualitative and stereological., Methods: One group of animals ( Wistar rats of both sex) was shame-pinealectomized (chirurgic treatment without pineal extirpation/control) and the other was submitted to surgical ablation of pineal gland.(experimental group). The animals were kept under the same ecologic conditions and they had free access to water supplies. Animals of the same group sacrificed at the same day between 10/14 hour to equal the effects of hormonal rhythm. The paraffin section died with HE (haematoxillin-eosin), PAS/alcian blue and impregnated by Bielschowsky method. For stereological analysis multipurpose M/42 test system was applied. Volume density of nodal structure and relative cellular distribution was evaluated., Results: Cortical tissue of lymph nodes of pinealectomized rats was reduced, particularly the paracotical regions. Only in the female rats, decreased number of lymphocytes was observed in the cortex and modularly cords. Stereological analysis confirmed that increased volume density of the medulla is the result of medullar sinus dilatation. Under regressive changes of the cortical structures can be considered the involutary processes in germinal centers and reduction of the younger lymphocyte forms. Macrophage was activated and increased PAS + an inclusion was observed on the cortico/medullary junction and in the modularly cords. Reticular stroma was intensively impregnated and fibrils more coarsed and fragmented., Discussion: Established changes in the lymph nodes of pinealectomized a rat was analogous with that observed after treatment with the pineal extracts but in the reverse means. It was evident that the structural dissociation of the reactivity had been established. Really, at one side we have involutive changes in lymphoid population and plasma cells but progressive in phagocytes and reticular cells. It is probably that increased concentration of corticosteroides and gonadal hormones after pinealectomy is responsible for these changes., Conclusion: Pineal gland-lymph nodes correlations established possibly via hypophyso-adreno-genital axis.

Haloperidol (4'-fluoro-4-[4-Hydroxy-4-p-chlorophenylpiperidino]-Butyrophenone), a neuroleptic, drug is the first choice in the treatment of schizophrenia. Experimental studies on rats show that haloperidol, at female, causes: decreasing of the ovarian weight, inhibition of the ovulation, producing a state of distrust and stimulation of lobuloalveolar development of the mammary glands and increasing of serum prolactin levels in both male and female rats. At male rats haloperidol causes damage of Leydig cells and cells depletion of seminal lineage with sequels on the excretory ducts level and accessory genital glands. Our pilot researches confirm these observations. The aim of this paper is to suggest an attention of the side effects of haloperidol, that's its stricter controlled use.

Ultrastructural characteristics of ductular parenchyma epithelial and myoepithelial cells were analysed in 18 cases of normal female breast tissue. Different physiological states have been compared and that pre- and postmenopausal. Nuclei and cytoplasm of epithelial and myoepithelial cells have been examined and compared. There were obvious signs of secretion and that apical protein granules, "dense-core" granules and light vesicles and lipid vacuoles and glycogen granules were accumulated in the deeper parts of premenopausal breast epithelial cells cytoplasm. Morphologic equivalents of secretion and accumulated glycogen were presented in the postmenopausal breast epithelial cells. Ultrastructural morphologic characteristics of postmenopausal myoepithelial cells were not different from those in premenopausal breasts.

In this paper it is been described method of electronic microscopy applied for discovering characteristic morphology of rotaviruses in samples of stools of infected and hospitalized patients. To have electronic microscopy as standard method it is necessary to know morphology or structure of the researched microorganism. In the second part of the paper we have made clinical epidemiological analysis of the rotavirus infection on the examined samples, and made comparison with result of other researches. Out of 78 patients with diarrhea, in 15 or 19.2% have been proofed presents of rotaviruses in the stool samples. All hospitalized patients had diarrhea (100%), vomiting was present in 90.9%, high temperature to 39C in 63.6% and over 39C in 36.4% patients. Stomachache was registered in 36.3% and blood in stool has not been found. Majority of the hospitalized had some respiratory syndromes. Time of hospitalization was between 6 to 13 days with average of 9.5 days. Death of hospitalized was not registered.

Melatonin, the major product of the pincal gland, is also synthesized in the retina of several vertebrate species. Retinal melatonin levels show a marked daily variation, with high levels at night and low levels during the light period. Melatonin rhythm generating system includes photodetector, circadian clock and melatonin synthesis machinery and they are located in pincal organ and retina. In both, light regulates daily variations in melatonin secretion by controlling the activity of arylalkylamine N-acetyltransferase (AANAT). In mammals, circadian system is comprised of three major components: the eyes, the hypothalamic suprachiasmatic nucleus (SCN) and the pincal gland. The SCN harbours the endogenous oscillator that is entrained every day to the ambient lighting conditions via retinal input. Among the many circadian rhythms in the body that are driven by SCN output, the synthesis of melatonin in the pincal gland functions as a hormonal message encoding for the duration of darkness. Dissemination of this circadian information relies on the activation of melatonin receptors, which are most prominently expressed in the SCN, and the hypophysical pars tuberalis (PT), but also in many other tissues. Melatonin is essential for rhythmic signaling in the PT. Here, melatonin acts in concert with adenosine to elicit rhythms in clock gene expression. By sensitizing adenylyl cyclase, melatonin opens a temporally-restricted gate and thus lowers the threshold for adenosine to induce cAMP-sensitive genes. This interaction, which regulates gene expression and pituitary output (by endocrine-endocrine interaction) represents general mechanism by which the master clock in the brain synchronizes clock cells in peripheral tissues that require unique phasing of output signals.

The qualitative and quantitative study of renal cortical structures was performed seven days after unilateral nephrectomy. Adult Wistar rats (10 male and 10 female) were ether-anaesthetized and the kidneys were removed by dorsolateral approach. Renal hypertrophy was determined by measurement of kidney dry mass. The samples of renal tissue were embedded in paraffin, sectioned at 6 microns and stained by azan and haematoxylineosin methods. The volume densities of renal corpuscles, the epithelium of tubules, luminal space of tubules and cortical interstitial structures were calculated using Weibel's multipurpose test system M 42. The qualitative analysis was performed to determine possible structural sex differences of cortical parenchyma during compensatory hypertrophy. There was no significant difference in volume densities of renal corpuscles and distal tubules between control and hypertrophic kidney. The volume density of the epithelium of proximal tubules and interstitial blood vessels were statistically significant increased in hypertrophic kidney compared to the values determined in control kidney. The volume density of luminal space of proximal tubules and interstitial tissues were statistically significant decreased in hypertrophy compared to control kidney. The data from present studies shows that the increase in epithelial volume of proximal tubules and interstitial blood vessels volume have the primary role in compensatory kidney enlargement after unilateral nephrectomy, while renal corpuscles do not participate significantly.

There some evidences that endocrine glands have marked influences on mast cells count The study was conducted to determine whether or not difference in mast cell count occurs in thymus gland of pincalectomized rats and to examine also sex difference in mast cell count under these condition adult Wistar rats were used. Pinealectomy was performed under light ether anesthesia. All animals were sacrificed by decapitation at 4 weeks after treatment. Samples were stained in Alcian-blue-PAS and, using Weibls multipurpose test system, the volume density (Vv), numerical density (Nv) and average volume of mastocytes were calculated. Analysis of morphometry has confirmed statistically significant increase in numerical density of mastocytes of pinealectomized female rats. The average volume of mastocytes has been also increased in both sex of animals after pinealectomy. The data from present studies show that there is marked sexual difference in reaction of mast cells after pinealectomy.

We have investigated the intramural blood vessels of the A-V segment in the conductive system of 20 human hearts using the method of light microscopy. The results of our study have shown that the A-V segment of the conductive heart muscles in human hearts has an abundant vascularisation. We have found the greatest density of the intramural net in the dorsal part of the A-V node; this density of blood vessels decreased toward the Hiss' bundle. After comparing these results with the earlier findings in the study of the intramural net in the S-A system we have found that A-V segment of the conductive heart system has a poorer blood supply in regard to S-A system. We have also found that the intramural net of blood vessels is weaker in the adjacent ventricular parts and in the interventricular septum. It cannot be said that there exists any surface vascular zone subepicardial, middle and deep sub-endocardiac--in the A-V segment of the conductive system of human heart.

The late effect of surgical ablation of the pineal gland on the morphometric changes of epithelial cells of rat thymus were investigated. The aim of this study was to determine a possible existence of sex related changes in the thymus epithelial cell after pinealectomy and to possibly clarify the correlation between the pineal gland and the thymus. Stereological ultrastructural parameters of the thymus cortical and medullar epithelial cells of male and female rats two months after pinealectomy are reported. A group of animals was submitted to surgery for ablation of pineal gland. The control group (shame-pinealectomized animals) underwent to the same surgical procedure but without removal of pineal gland. Animals were sacrificed 60th days after surgery. Para-sagittal thymus specimens were fixed by immersion in glutaraldehyde and processed for transmission electron microscopy. The volume and surface density (Vv, Sv) of nucleus and cytoplasm of cortical and medullar thymus epithelial cells were calculated using the Weibel's multipurpose test system and multilevel sampling technique on electron micrographs. Volume and surface density of mitochondria (Vvm, Svm), endoplasmic reticulum (Vvr, Svr), vacuole (Vvv) as well as numerical density of mitochondria (Nvm) were evaluated at different magnification levels. Our analysis confirmed a statistically significant increase in Vv of endoplasmic reticulum and vacuoles in both sex of pinealectomized rats. Sv of plasmalema, endoplasmic reticulum and mitochondrial membrane were markedly increased in thymus medullar epithelial cells of pinealectomized rats. Vv of mitochondria was significantly increased in cortical epithelial cells of pinealectomized animals. These results confirm that a correlation between pineal gland and thymus exists. However the present findings seem to support the concept of sex independent inhibitory action of pineal gland on thymus cortical and medullar epithelial cells.

Stereological characteristics of ductular parenchyma epithelial cells are analysed ultrastructurally on 8 cases of normal breast tissue. Different physiological states have been compared and tahat pre- and postovulatory. Volume density (VV), surface density (SV) and specific surface density (SV/VV) of nuclei and epithelial cells cytoplasm have been stereologically examined and compared. Postovulatory, the volume density (VV) and surface density (SV) of nuclei as well as specific surface density (SV/VV) of epithelial cells cytoplasm are much less, while a volume density (VV) of epithelial cells cytoplasm is greater.

The late effect of surgical ablation of pineal gland on the morphometric changes in epithelial cells of rat thymus were investigated. The aim of this study is to determine a possible existence of sex-different changes in composition of the epithelial cell component unit long after pinealecotmy what could be important for the subtle understanding of mutual correlation between pincal body and thymus. This article presents results of stereological ultrastructure parameters of thymuscortical and medullar epithelial cells of male and female rats two month after pinealectomy. The experimental animals were divide into two groups: an experimental one (pinealectomized) and the control group (shampinealectomized). Pinealectomized animals were submitted to surgical ablation of pineal gland while the control were undertaken the same surgical treatment but without removal of the pineal gland. Animals were sacrificed 60 th days following the surgery treatment. Parasagital pieces of thymus tissue were fixed by means of immersion in glutaraldehyde and prepared for transmission electron microscopy. Using Weibls multipurpose test system and multilevel sampling technique on electron micrographs the volume and surface density of nucleus (Vu, Sv) and cytoplasm of cortical and medullar thymus epithelial cells were calculated. At the different magnification level were established the volume and surface density of mitochondria (Vvm, Svm) endoplasmic reticulum (Vvr, Svr), vacoule(Vuv) as well as numerical density of mitochondria (Nvm). Our analysis has conformed statistically significant increase in Vv of reticulum and vacuole in both sex of pinealectomized rats. Sv of plasmalema, reticulum and mitochondrial membrane are markedly increased in thymus medullar epithelial cells of pienalectomized rats. Vv of mitochondria is significantly increased in cortical epithelial cells of pienalectomized animals. Results allow us to confirm that mutual correlation between pineal gland and thymus exists but present findings seem to support the concept of sex independent inhibitory action of pineal gland on thymus cortical and medullar epithelial cells.

The mammary glands of primigravid Wistar rats were investigated by stereological analysis in conditions of lead acetate administration via drinking water. The experiment was made in early summer period when absorbing ability of rat intestinum for lead is highest. Morphological state of glands was observed on 7th, 14th and 21st day of pregnancy. Groups of control animals were drinking deionized water but groups of experimental animals were drinking deionized water with added lead acetate. On paraffin sections coloured by HE method, volume density (VV) of glands structural elements were determined by multipurpose test system M42. Stereological analysis shows that lead diminishes the proliferative capacity of the mammary parenchyma and changes the morphofunctional differentiation of the overall structure in mammary gland during pregnancy. At the same time lead modifies quantitative trait of the mammary gland, i.e. the composition of the volume units in organ, without changing intramammary syncornization between the epithelium and lipocytes.

The effects of pinealectomy on the dynamics of morphometric changes in interdigitating cells(IDC) of rat thymus were investigated. The experimental animals were divided into two groups: an experimental one and the control group. Animals from the first group were subjected to pinealectomy while the second group were treated in the same manner, but without the removal of the pineal gland. All the animals were sacrificed 60. days following the surgery. The thymus tissue were fixed by means of immersion and prepared for transmission electron microscopy. Using Weibl's multipurpose test system and multilavel sampling technique on electron micrographs, the nuclear volume density(Vvn) and cytoplasmic volume density(Vvc) were calculated. At the different magnification level established the surface density(Sv) of nucleoid and cell membranes as wel as surface density of rough endoplasmic reticulum and mitochondrial membranes (Svm) and their volume density. Our analysis has confirmed statistically significant increase in Vv of the nucleus of pinealectomized rats. The average volumen of IDC has been also increased after pinealectomy as well as Vv, Nv and Sv of the mitochondria. The present findings seem to support the concept of inhibitory action of pineal gland on thymus IDC.

The aim of the study was to determine the effects of exogenous melatonin on Leydig cells in irradiation stress. Nuclear and cytoplasm surface of Leydig cells in sham pinealectomized and pinealectomized adult Wistar rats was determined after their total irradiation with 8 Gy of gama rays produced by 60 Co and with previously performed 14 days treatment by injecting of melatonin solution in a daily dose of 0.2 mg. Rats testes were histologically prepared 17 days after irradiation. Total melatonin administration significantly decreased surface of Leydig cells including both decrease of their nuclear and cytoplasm surface in irradiated sham pinealectomized and pinealectomized rats. The results suggested about direct effects of exogenous melatonin on Leydig cells in irradiation stress.