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.

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.