Introduction: Fusimotor neurons innervate intrafusal muscle fibers within muscle spindles. They are of at least three different types: static and dynamic axons innervating static and dynamic bag fiber respectively. Different areas in central nervous system are known to influence their activity. In present study, cortical control of the gamma motoneurons of tenuissimus muscle spindle in eight anaesthetized cats was investigated using direct visual method. Materials and Methods: Cats of either sex, weighing 2-3.8 kg were anaesthetized with sodium pentobarbitone (45 mg/kg), tracheotomized and intubated, obturator and femoral nerves cut and all the hindlimb muscles except tenuissimus denervated (right sciatic nerve also eat). Muscle spindles uncovered microsurgically and placed in the bath overviewed by a phillips camcorder. Right sensorimolor cortex was then exposed and a paraffin pool was made using skull skin. 0.3 to 3 mA current were applied, both anodal and cathodal, within a five second period of a 12 second stimulation window. Spontaneous and evoked intrafusal movements were monitored and taped for furthur analysis. Results: The findings confirmed the evidence for independent cortical control of different types of static gamma motoneurons and revealed a topographical mapping of the sensorimotor cortex in relation to the type of gamma motoneurons recruited, either static or dynamic. Static effects were elicited following stimulation of a wide area across the sensorimotor cortex, the postcruciate dimple being almost at the center. Within that region, a "dynamic area" was identified from which dynamic effects were clearly elicited during stimulation. Conclusion: Different types of static gamma axons and dynamic gamma axon can be controlled independently on cerebral activation. The state of anaesthesia was crucial in obtaining reproducible results and its variation could alter the fusimotor effect from static to dynamic or even from excitation to inhibition.

Introduction: One of the methods of cancer treatment is use of chemotherapic drugs. Breast cancer is a common disease that chemotherapic drugs have not treated it yet.In this research, cell proliferation inhibition in MCF-7 cells, a human breast carcinoma cell line, after treatment with Cisplatin, an anticancer drug is studied.Material and Method: At first, after cell counting with trypan blue stain, equal cells were added to flasks and flasks were divided into two control and experimental groups.In experimental group, 1 micro mole cisplatin exposured in 1 hour, where control group with normal saline solution. After that, flasks were incubated for 48 hours.After passing this time, attached cells of two control and experimental groups, were stained with trypan blue for cell counting, and with toloiden blue for light microscopy individually. Obtained results were divided into two section, cell counting and light microscopy.In cell counting, obtained results were evaluated with Mann - Withney statistical test.Results: Results showed that number of attached cells in experimental group was reduced. In light microscopy, morphological features of attached MCF-7 cells in two groups were similar.Conclusion: Through that, attached MCF-7 cells are proliferating, so we can say that without altering in morphological features, Cisplatin causes inhibition in cell proliferation of MCF-7 cells.

The internal mammary artery (IMA) is currently the preferred conduit for myocardial revascularization. However, pre-operative vasospasm and a hypoperfusion state during maximal exercise may limit its use as a bypass graft. The mechanism of spasm has not been clearly defined. Since ß-adrenoceptor activation plays a major role in vasorelaxation, the present study was carried out to investigate the ß-adrenoceptor responsiveness of human IMA smooth muscle.For this purpose, IMA was obtained from patients with atherosclerosis of coronary artery whom have undergone coronary artery bypass. The endothelium denuded rings of IMA were placed on platinum wires (L-shaped) in a Krebs solution containing tissue bath, and were connected to an isometric transducer. It was found out that Isoproterenol produced a dose-dependent relaxation in endothelium-denuded MA segments, precontracted with phenylephrine (maximal relaxation was 46.33 ±5.45%). Isoproterenol-induced relaxation was inhibited by atenolol (10-6M) and propranolol (2 x 10-7M). While atenolol-induced inhibition was partial, propranolol-induced inhibition was complete in a majority of the segments. BRL 37344, a selective ß3-adrenoceptor agonist, produced a dose-dependent relaxation in phenylephrine precontracted rings of endothelium-denuded IMA (maximal relaxation was 40.35 ±4.07%). Cyanopindolol, a ß-adrenoceptor partial agonist, produced a marked relaxation in endothelium-denuded IMA rings, precontracted with phenylephrine (maximal relaxation was 58.65±6.2%). Cyanopindolol-induced relaxation was resistant to blockade by propranolol (2 x 10-7 M). In addition, spontaneous contractions of IMA rings were observed in some of the cases that were inhibited by isoproterenol and BRL 37344. This observation may indicate the important role of ß3-adrenoceptor activation in prevention of human IMA spasm.Therefore, it is concluded that human IMA smooth muscle possesses both ß1-and ß2-radrenoceptors. The existence of ß3-adrenoceptorip this tissue is also suggested.

Cell death is classically divided into two modes; Apoptosis and Necrosis. Characterization and determination of cell death types are essential in treatment management. The mode of cell death is controversial in Mcf-7 cell line following cisplatin treatment. In this study, electron microscopy as golden criteria was carried out for determination of cell death mode. McF-7 cell line was cultured in complete medium. At late exponential phase, the cultured cells were divided into two control and experimental groups. Experimental group was treated by 1µM cisplatin for one hour. Both groups were washed and then incubated for 48 hours. After completion of incubation time, the attached and detached cells were separately collected and prepared for electron and light microscopy. Results indicated, morphology of attached cells in experimental group were similar to attached cells of control group. Attached cells were seen with cell membrane microvillie, nuclear uochromatin and normal organelles. The detached cells of both control and experimental groups were characterized three types of cells; apoptotic, secondary necrotic and normal cells. Apoptotic cells; were observed with nuclear heterochromatin, disappearing of microvillie, appearing of cytoplasmic vacoules and condensation of cytoplasm. Finally some apoptotic cells were Fragmented into apoptotic bodies and some other cells were undergone to secondary necrosis. The number of detached cells was high following cisplatin treatment. In conclusion, the mode of cell death in Mcf-7 is apoptosis following cisplatin treatment.