AIM: To investigate the effects of a 10-weeks treatment with angiotensin Ⅱ (Ang Ⅱ) subtype I receptor antagonist losartan on vascular remodeling of thoracic aorta in male spontaneously hypertensive rats (SHR). METHODS: SHR were treated from 16 to 26 weeks of age with losartan at 15 mg/kg?d -1 or 0.75 mg/kg?d -1. RESULTS: Losartan (15 mg/kg?d -1) treatment significantly decreased systolic blood pressure compared with the control group, while losartan (0.75 mg/kg?d -1) had no the effect, losartan(15 mg) prevents the development of aortic hypertrophy by preventing hypertrophy of vascular smooth muscle cells (VSMC). In the losartan 0.75 group, these parameters were not changed. But in the losartan 15 and losartan 0.75 groups, the collagen content of the aortic media decreased significantly. CONCLUSION: It is inferred that the effect of Ang Ⅱ on stimulating VSMC growth of the aorta in SHR is dependent on arterial pressure, while the effect on collagen fibers is through pressure independent mechanism.

AIM: To investigate the effects of angiotensin II receptor antagonist on remodeling of renal arterioles in hypertension. METHODS: Eighteen 4 weeks old male rats were divided into three groups: Wistar-Kyoto rats (WKY) for normotensive group, and spontaneously hypertensive rats (SHR) for hypertensive group, and SHR treated with losartan orally (15 mg?kg -1 ?d -1 ). The rats were raised to 16 weeks old. The morphometric parameters of the renal arterioles, and the widths of vascular smooth muscle cells (VSMC) and intercellular space were studied on kidney slices by light microscope and electromicroscope respectively, combined with computer-assistant image analysis system. The minimal renal vascular resistance (RVR min ) was studied by isolated kidney perfusion system. RESULTS: The systolic blood pressure of the tail artery, wall thickness, wall area, ratio of wall thickness to inner diameter, width of VSMC of renal arterioles and RVR min were all smaller or lower in losartan group than those of SHR. CONCLUSION: Ang II receptor antagonist losartan can prevent the remodeling of renal arterioles in SHR.

A teaching method called cross-disciplinary joint teaching,which integrated the neural system-based physiology,anatomy and histology from gross morphology to micmstructure,then to physiological function,was carried out on 2010 clinical eight-year program medical students.Jointteaching method was carried out throughout the whole courses.That means in three subjects related to the discipline,teachers compile the textbook,discuss teaching scheme,compile cases,collectively prepare lessons,and attend lectures and discussion together.Flexible teaching forms such as casebased teaching,problem-based teaching and bilingual teaching were also run through the whole processes of the teaching.Compared with the traditional teaching model,cross-disciplinary joint teaching not only achieves the integration of morphology,microstructure and functions of nervous system,but also has a priority of helping the students to develop a more efficient learning ability such as initiative study and thinking extension.

The cross-disciplinary form-function joint teaching of nervous system centered on organ was carried out in the Second Military Medical University for medical students of the eight-year system according to its actual situation.The nervous system was selected as the teaching content and problem-based learning was used,with the fusion of three aspects of knowledge of histology and embryology,physiology and human anatomy and the integration of teachers from different disciplinarians.The effect was good.

Objective To observe the differentiation of bone marrow multipotent adult progenitor cells(MAPCs)into skin tissue cells of rats in vivo. Methods Magnetic activated cell sorting (MACS)was used to remove MAPCs from bone marrow of male rats through negative screening.Tail vein injection with combined with MAPCs Was done in C57BL/6 mice with skin wound and nude mice with immunodeficieney.Immunohistochemical staining was used to examine the expression of MHCI antigen in the healed skin of donor SD rats. Results Positive MHCI cells were found in the epidermal fundus and Some hair follicle-like structures of the healed skin of C57BL/6 mice.Hair follicle-like structure appeared in the healed skin of nude mice group,in which positive MHCI cells were found in the basal epidermal and some hair follicle-like structures. Conclusions During skin damage,MAPCs can migrate to the injured skin area and skin adnexa hair foilicle area,transform into epidermal cells and hence participate in the healing of the wound skin.

Objective: To observe morphological changes of epithelial-mesenchymal transition in the early stage of mice renal interstitial fibrosis. Methods: Renal interstitial fibrosis was induced by unilateral ureteral obstruction(UUO) in mice. Histological and immunohistochemical methods were used to analyze pathological changes and α-SMA expression in renal tissue.Argentum hexamethylenamine staining and transmission electron microscopy were used to observe changes of the renal tubule basement membrane. Gelatin zymographic analysis was used to observe the expression of MMP2 and MMP9 in renal tissue.Results:The mice suffered from renal interstitial fibrosis were identified by histological analysis and α-SMA positive cells in renal tissue. Argentum hexamethylenamine staining and transmission electron-microscopy showed that the renal tubule basement membrane disrupted locally and renal tubule epithelial cells invaded into the renal interstitium in the early stage of renal interstitial fibrosis. Gelatin zymographic analysis showed that the expression of MMP2 and MMP9 was increased transitorily in the early stage of renal interstitial fibrosis. Conclusion: Renal tubule basement membrane disruption, renal tubule epithelial cells invasion into the renal interstitium, and the expression of MMP2 and MMP9 are involved in the development of renal interstitial fibrosis.