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.