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We investigated the contribution of the duration of overdistention (DOD) to rat bladder function and morphology and explored its possible molecular mechanisms. Bladder overdistention was induced in male Sprague-Dawley rats (200-250 g) by an infusion of saline. Forty rats were divided into 5 groups submitted to different DOD, i.e., 1, 2, 4, and 8 h, and control. Bladder function was evaluated by cystometry. Morphological changes were observed by light and transmission electron microscopy. Compared to control (44.567 ± 3.472 cmH2O), the maximum detrusor pressure of groups with 2-, 4- and 8-h DOD decreased significantly (means ± SEM): 32.774 ± 3.726, 31.321 ± 2.847, and 29.238 ± 3.724 cmH2O. With the increase of DOD, inflammatory infiltration and impairment of ultrastructure were more obvious in bladder tissue. Compared to control (1.90 ± 0.77), the apoptotic indexes of groups with 1-, 2-, 4-, and 8-h DOD increased significantly (6.47 ± 2.10, 10.66 ± 1.97, 13.91 ± 2.69, and 18.33 ± 3.28%). Compared to control (0.147 ± 0.031/0.234 ± 0.038 caspase 3/β-actin and Bax/Bcl-2 ratios), both caspase 3/β-actin and Bax/Bcl-2 ratios of 1-, 2-, 4-, and 8-h DOD increased significantly (0.292 ± 0.037/0.508 ± 0.174, 0.723 ± 0.173/1.745 ± 0.471, 1.104 ± 0.245/4.000 ± 1.048, and 1.345 ± 0.409/8.398 ± 3.332). DOD plays an important role in impairment of vesical function and structure. With DOD, pro-apoptotic factors increase and anti-apoptotic factors decrease, possibly contributing to the functional deterioration and morphological changes of the bladder.

Objectives To investigate the roles of steroid hormones, including estrogen, progesterone, and testosterone, in the morphology and vascularization of the female bladder. Methods A total of 70 adult, female Sprague-Dawley rats were divided into 7 groups: group 1, sham; group 2, ovariectomized rats without treatment; group 3, low-dose estradiol; group 4, high-dose estradiol; group 5, progesterone; group 6, estradiol combined with progesterone; and group 7, testosterone. All were given for 4 weeks. The serum steroid hormone levels were determined by radioimmunoassay. The total weight and thickness of the bladder were measured. Morphologic changes were observed under light and electron microscopy. The expression of vascular endothelial growth factor (VEGF) in the bladder was evaluated by immmohistochemistry and Western blotting. Results The ovariectomized rats had a thinner bladder wall compared with the sham group (0.97 ± 0.11 mm vs 1.10 ± 0.10 mm, P < .05) and widened spaces between the detrusor muscle fascicles with collagen deposit. Estrogen reversed these changes, and testosterone increased the thickness of the bladder wall to 1.26 ± 0.12 mm (P < .05). VEGF staining was mainly located in the urothelium and endothelial cells, with weak staining in the smooth muscles. VEGF was almost absent in the urothelium after ovariectomy. In the estrogen- and androgen-treated groups, although the expression of VEGF was significantly greater than that in the nontreated ovariectomized group, it was still lower than normal. Conclusions Our findings suggest the importance of steroid hormones in maintaining the integrity of the bladder structure and regulating the expression of VEGF in the female urinary tract. Both estrogen and androgen can reverse the bladder muscle atrophy induced by ovariectomy. However, the decline in VEGF expression in the bladder cannot be fully recovered with either estrogen or androgen replacement.

To determine the feasibility of transfecting penile corpora cavernosa with pcDNA3/vasoactive intestinal polypeptide (VIP) cDNA, which encodes for VIP in streptozotocin (STZ)-diabetic rats, to clarify whether transfection of VIP cDNA into the cavernosum affects the physiological response to cavernosal nerve stimulation, and whether this process would affect other organs in the diabetic rat model in vivo.pcDNA3/VIP cDNA was injected into the corpus cavernosum of STZ-induced diabetic Sprague-Dawley rats. The intracavernosal pressure (ICP) and response to electrical stimulation of the cavernosal nerve (15 Hz, 1.5 ms, 20 V, 1 min) were measured in subsamples of rats at 1, 3, 7 and 14 days after injection; after measuring the ICP the animals were killed, and penile, hepatic, renal artery and abdominal aorta tissue samples were frozen in liquid nitrogen and stored at -80 degrees C. The gene expression of VIP in all samples, assessed as the expression of VIP mRNA, was estimated using a semiquantitative reverse-transcription polymerase chain reaction.The mean amplitude of ICP and expression of VIP mRNA in the cavernosa of the VIP-treated rats was greater at 1, 3, 7 and 14 days after injection (P0.05) than in the control animals. There were no changes in the expression of VIP mRNA in hepatic, renal and abdominal aorta samples after injection (P0.05).VIP cDNA is easily incorporated into corpus cavernosum, and the expression is sustained foror = 2 weeks in the penis in vivo. The transfer of VIP is capable of altering the physiologically relevant erectile response, as measured by an increase in the ICP after stimulating the cavernosal nerve. The intracorporal micro-injection of pcDNA3/VIP cDNA had little effect on the expression of VIP mRNA in other important organs.

To study the androgen dependence of the neurotransmitter, calcitonin gene-related peptide (CGRP) in rat penis.Forty-four Sprague-Dawley rats were randomly divided into Group A (intact controls), Group B (castrated) and Group C (gavaged with finasteride 4.5 mg.kg(-1).day(-1)). Four and ten weeks later respectively, half of rats in each group were anaesthetized. Blood samples were taken for the measurement of serum testosterone and dihydrotestosterone (DHT) by means of radioimmunoassay. Penile samples were harvested for the investigation of calcitonin gene related peptide (CGRP)-immunoreactive nerve fibers with immunohistochemistry. The computer-assisted imaging analysis system was applied to calculate the area proportion of the CGRP-positive nerve fibers (CGRP-PNF) in each group.1) Both 4 and 10 weeks later, testosterone and DHT levels in Group B decreased significantly compared with those in Group A, (P0.05, P0.01, respectively); DHT level in Group C was also significantly decreased in comparison with that in Group A for both 4- and 10- week animals (P0.05); 2) There was no significant differences in area proportion of CGRP-PNF among Groups A, B and C 4 weeks after treatments (P0.05); However, 10 weeks later, the proportion of CGRP-PNF in Groups B and C was significantly less than that in Group A (P0.01); 3) The proportion of CGRP-PNF of 4-week animals in Groups B and C was significantly higher than that of 10-week animals (P0.05).The expression of neurotransmitter, CGRP may depend on androgens, including testosterone and DHT in rat penis.

Lead is an important environmental pollutant that exerts potent toxic effects on many organs. The toxic effects of lead are less well known for adult brain than for children. We investigated the morphological changes and amyloid precursor protein (APP) accumulation in the adult rat hippocampus following exposure to lead. Forty rats were divided into two groups of 20. One group was exposed to 580 parts per million (ppm) lead acetate and other group to an identical concentration of sodium acetate as a control group. After exposure to lead for 3 months, the hippocampus was examined by electron microscopy and APP levels in the hippocampus were detected using immunohistochemistry. Lead levels in the blood of rats exposed to lead were significantly higher than in the controls. The morphological changes in the hippocampus included mitochondrial degeneration, apoptosis and abnormal synapses in the rats exposed to lead. APP in hippocampus was increased significantly in the group exposed to lead compared to controls. We determined that lead exposure causes accumulation of APP and morphological changes in the adult rat hippocampus.

To investigate the effects of tumor cell-derived Sema3A on the immunological functions of murine dendritic cells (DCs).Lung adenocarcinoma A549 cells were transfected with small interference RNA, Si-Sema and Si-mut, and the interference efficiency was determined by real-time PCR and Western-blot. The concentrated supernatants from cultured tumor cells, Si-Sema and Si-mut-infected tumor cells were subjected to DCs respectively. The immunophenotypes of DCs were analyzed by flow cytometry, the production of IL-12P70 and the ability of DCs to stimulate DO11. 10 T cells secreting IFN-gamma and IL-2 were detected by enzyme linked immunosorbent assay (ELISA).Knockdown with Si-Sema3A significantly decreased the secretion of Sema3A by A549 cells in comparison with the Si-mut cells. DCs exposed to supernatants from Si-Sema cells showed elevated levels of MHC, CD40 and CD80, more production of IL-12P70, and enhanced capability of activating antigen-specific T cells, as evidenced by the remarkably increased levels of IFN-gamma and IL-2.A549 cells secrete Sema3A to inhibit the maturation and functions of DCs, which might be associated with the unidentified mechanism of immune evasion by tumor cells.

Thymic stromal lymphopoietin (TSLP) emerges as a central mediator of T helper cell (Th)2-dominant allergic diseases. However, the role of TSLP receptor (TSLPR) in allergen-induced Th2 priming, and the effects of TSLP signaling blocking on the development of asthma remain unclear. Here we showed that allergen challenge caused a rapid accumulation of TSLP in the airways of asthmatic mice, correlating well with eosinophils counts and interleukin (IL)-5 productions. When TSLP signaling was blocked by intratracheal administration of anti-TSLPR antibody before sensitization, eosinophilic airway inflammation, goblet cell hyperplasia and Th2 cytokines productions were significantly reduced. The alleviating effects of TSLPR blocking were achieved by inhibition of maturation and migration of airway dendritic cells (DCs), as well as their abilities of initiating CD4+T cell responses. Thus, local application of anti-TSLPR prevented Th2-mediated airway inflammation, at least partly, by regulating DCs function, which might be exploited to develop novel treatments for asthma.

AIM To comparatively study the preventive effect of gelatinizedly-modified chitosan film on peritoneal adhesions induced by four different factors in rats. METHODS Chitosan was chemically modified by gelatinization, and made into films of 60 microm in thickness, and sterilized. Two hundred Sprague-Dawley rats were randomly divided into five groups, Sham-operation group (group A), wound-induced adhesion group (group B), purified talc-induced adhesion group (group C), vascular ligation-induced adhesion group (group D), and infection-induced adhesion group (group E), respectively. In each group, the rats were treated with different adhesion-inducing methods at the cecum of vermiform processes and then were divided into control and experimental subgroups. Serous membrane surface of vermiform processes were covered with the films in the experimental subgroups, and no films were used in the control subgroups. After 2 and 4 wk of treatments, the abdominal cavities were reopened and the adhesive severity was graded blindly according to Bhatia's method. The cecum of vermiform processes were resected for hydroxyproline (OHP) measurement and pathological examination. RESULTS Adhesion severity and OHP level: After 2 and 4 wk of the treatments, in the experimental subgroups, the adhesions were significantly lighter and the OHP levels were significantly lower than those of the control subgroups in group B (2 wk: 0.199 +/- 0.026 vs 0.285 +/- 0.041 microg/mg pr, P < 0.001; 4 wk: 0.183 +/- 0.034 vs 0.276 +/- 0.03 microg/mg pr, P < 0.001), D (2 wk: 0.216 +/- 0.036 vs 0.274 +/- 0.040 microg/mg pr, P = 0.004; 4 wk: 0.211 +/- 0.044 vs 0.281 +/- 0.047 microg/mg pr, P = 0.003) and E (2 wk: 0.259 +/- 0.039 vs 0.371 +/- 0.040 microg/mg pr, P < 0.001; 4 wk: 0.242 +/- 0.045 vs 0.355 +/- 0.029 microg/mg pr, P < 0.001), but there were no significant differences in groups A (2 wk: 0.141 +/- 0.028 vs 0.137 +/- 0.026 microg/mg pr, P = 0.737; 4 wk: 0.132 +/- 0.031 vs 0.150 +/- 0.035 microg/mg pr, P = 0.225) and C (2 wk: 0.395 +/- 0.044 vs 0.378 +/- 0.043 microg/mg pr, P = 0.387; 4 wk: 0.370 +/- 0.032 vs 0.367 +/- 0.041 microg/mg pr, P = 0.853); Pathological changes: In group B, the main pathological changes were fibroplasias in the treated serous membrane surface and in group D, the fibroplasia was shown in the whole layer of the vermiform processes. In group E, the main pathological changes were acute and chronic suppurative inflammatory reactions. These changes were lighter in the experimental subgroups than those in the control subgroups in the three groups. In group C, the main changes were foreign body giant cell and granuloma reactions and fibroplasias in different degrees, with no apparent differences between the experimental and control subgroups. CONCLUSION The gelatinizedly-modified chitosan film is effective on preventing peritoneal adhesions induced by wound, ischemia and infection, but the effect is not apparent in foreign body-induced adhesion.

To investigate the characteristics of genesis and development of peritoneal adhesion by different causes.236 rats underwent laparotomy with their vermiform processes lifted up and were randomly divided into 5 groups: Group A (control group), with the vermiform process exposed to air for 5 min, Group B, with the vermiform process smeared with talcum powder; Group C, with the vermiform process scraped by scalpel; Group D, with the tip of vermiform process stabbed by needle so as to squeeze the contents of intestine to cause infection; and Group E, with the artery of vermiform process ligated. Then the abdominal incision was sutured. 1, 2, 4, and 6 weeks after the treatment 11-12 rats from each group were randomly to undergo laparotomy. The degree of adhesion was graded blindly by Bhatia's method. The vermiform process was resected to undergo pathological examination and examination of the level of organ hydroxyproline (OHP) was detected.(1) At different time points the adhesive grades of Groups B-E were all significantly higher than that of Group A (all P0.05) and the adhesive grades of Groups B and D were both significantly higher than those of Groups C and E (both P0.05). There were no significant differences in the adhesive degree 1, 2, and 4 weeks after the treatment between Groups C and E, however, the adhesive degree of Group E was significantly lower than that of Group C (P0.05). (2) There were not significant differences in the OHP levels at any time points in Group A (all P0.05). There were not significant differences in the OHP levels 1, 2, and 4 weeks after the treatment (all P0.05), and the levels 8 weeks after the treatment were all significantly lower than those 1, 2, and 4 weeks after the treatment (all P0.05) in Groups B, D, and E. In Group C the OHP level 2 weeks after the treatment was 0.275 +/- 0.031 microg/mg protein, significantly lower than that 1 week after (0.221 +/- 0.036 microg/mg protein, P0.05), and the OHP level 8 weeks after the treatment was 0.254 +/- 0.039 microg/mg protein, significantly lower than those 1, 2, and 4 weeks after (all P0.05). The OH levels 1, 2, and 4 weeks after the treatment of the 4 experimental groups were all significantly higher than that of the control group (all P0.05). 8 weeks after the treatment the level of OHP of Groups B was significantly higher than that of Group A (P0.05), however, the OHP levels of Group C, D, and E had all decreased to almost similar to that of Group A (all P0.05). (3) The adhesive degrees of Groups C and E were significantly positively correlated with the OHP level (both P0.05), however, the adhesive degrees of Groups B and D were not significantly correlated with the OHP level (both P0.05). The adhesive degrees 1, 2, and 4 weeks after the treatment of the 5 groups were all significantly positively correlated with the OHP levels (all P0.05, however, the adhesive degrees 8 weeks after the treatment of the 5 groups were all not significantly correlated with the OHP levels (all P0.05). (4) The main pathological changes of Group B were foreign body granuloma reaction and fibroplasia in Group B and unspecific inflammatory reaction and fibroplasia in Groups C, D, and E.Abdominal adhesions resulting from different causes show different characteristics. The abdominal adhesion caused by foreign bodies and that caused by infection are relatively severe and more difficult to recover than those caused by injury and ischemia. It is more reliable to use OHP level as a marker of abdominal adhesion in the early stage.

Chronic lead (Pb) exposure during development is known to produce learning deficits. Nitric oxide participates in the synaptic mechanisms involved in certain forms of learning and memory. This study was designed to clarify whether Pb-induced impairment in learning and memory was associated with the changes of nitric oxide levels in mice brains.Sixty Balb/c mice aged 10 days were chosen. A model of lead exposure was established by drinking 0.025%, 0.05%, 0.075% lead acetate, respectively for 8 weeks. The controls were orally given distilled water. The ability to learn and memorize was examined by open field test, T-water maze test. In parallel with the behavioral data, NO level of hippocampus tissue was detected by biochemical assay.Compared with control groups, (1) the weight of 0.075% group was significantly reduced (P0.05); (2) The number of times in mice attaining the required standards in T-water maze test was lower in 0.075% group (P0.01). No significant difference was found between experimental and control groups in open field test (P0.05); (3) NO level of mouse hippocampus tissue was decreased in 0.075% group (P0.01).The findings suggest that decreased hippocampus NO level may contribute to the Pb-induced deficits in learning and memory processes.

To clarify the ultrastructural changes of penile tunica albuginea (TA) in streptozotocin (STZ)-induced diabetic rats.Intraperitoneal injection of STZ was used to induce diabetes mellitus (DM) in 12 Sprague Dawley rats. Ten rats (age and weight-matched) were used as control. Blood samples from the tail snips of the rats were used for the determination of serum glucose levels with SureStep Plus Blood Meter. At week 4 and 10 after the injection, half of the rats in each group were sacrificed and penile samples were obtained from the middle third of the penile shaft for the examination of TA under scanning electron microscopy.In the diabetic group, the serum glucose levels were higher (P0.01 at both time points) and the TA were thinner (P0.05) than those of the controls. In the control group, the fibers of TA were rich and arranged regularly and undulated, while in the diabetic group, the fibers were diminished, lost the undulations and were arranged irregularly.In rats, DM appeared to impair the penile TA ultrastructures and this impairment could contribute to diabetic erectile dysfunction in part by impairing the veno-occlusive function.

To investigate the ultrastructural changes of penile corpus cavernosum and tunica albuginea in rats treated with castration or finasteride.Eighteen male Sprague-Dawley rats of nine weeks old were randomly divided into three groups with 6 rats each. Group A served as the control, Group B was castrated and Group C, treated with finasteride. Four weeks later, rats were anesthetized and blood samples obtained for the determination of serum testosterone (T) and dihydrotestosterone (DHT) levels; penile tissues were taken for scanning electron microscopy.The T, free T and DHT levels in Group B and the DHT level in Group C were significantly lower than those in Group A (P0.05). The tunica albuginea was significantly thinner in Group B than that in Group A (P0.05), but there was no significant difference between Group C and Group A (P0.05). Elastic fibers in the tunica albuginea of Group A were very rich and arranged regularly and undulatedly, but in Group B, most of the elastic fibers were replaced by collagenous fibers. In Group C, the tunica albuginea was mainly composed of thick and irregular-arranged collagenous fibers. In Group A, there were abundant smooth muscle fibers in the trabeculae of corpus cavernosum, but they were much less in Group C and scarce or even disappeared in Group B. In Groups B and C, the diminished/disappeared smooth muscle fibers were replaced by irregularly arranged collagenous fibers.In rats, androgen is essential for maintaining the normal structure of penile tunica albuginea and corpus cavernosum.

To study the effects of chitosan gel and blending chiston/gelatin film on preventing peritoneal adhesion in rats.SD rats were randomly divided into 2 groups, group A treated with chitosan gel and group B with blending chiston/gelatin film. In group A, rats were randomly subdivided into 3 subgroups as groups A1, A2 and A3, and different methods were used to induce peritoneal adhesions at the dead end of vermiform process in each group as follows: Group A1 with trauma, A2 with talc powder and A3 with ligation of blood vessel. In each subgroup, rats were redivided into control group and experimental group whose treated vermiform processes were respectively coated with chitosan gel and normal saline immediately after the adhesion-induced treatments. In group B, all the rats received traumatic adhesion-induced treatments and then were randomly divided into 4 groups (groups B1, B2, B3, B4). Group B1 served as control group and were coated with normal saline in the vermiform processes immediately after the treatments, and groups B2, B3 and B4 with 100% chitosan film, chitosan film containing 10% gelatin and chiston film containing 50% gelatin, respectively. At 2 and 4 wk after the above treatments, half of the rats in each terminal group were belly opened, and the peritoneal adhesive situation was graded and histopathological changes were examined.(1) In group A, regarding peritoneal adhesion situation: At both 2 and 4 wk after the treatments, for groups A1 and A3, the adhesive grades of experimental groups were significantly lower than those of the control group (2 wk: H = 4.305, P0.05 for A1, H = 6.743, P0.01 for A3; 4 wk: H = 4.459, P0.05 for A1, H = 4.493, P0.05 for A3). However, of group A2, there was no significant difference between the experimental and control groups (2 wk: H = 0.147, P0.05; 4 wk: H = 1.240, P0.05). Regarding pathological changes: In groups A1 and A3, the main pathological change was fibroplasia. In group A2, the main changes were massive foreign-body giant cell reaction and granuloma formation with fibroplasia of different degrees. (2) In group B, regarding degradation of film: With increase of the blended gelatin concentration, degrading speed of the film accelerated significantly. Regarding peritoneal adhesion situation: At both 2 and 4 wk after the treatments, the adhesive grades of B1 were the lowest among the four subgroups of B (2 wk: H = 29.679, P0.05; 4 wk: H = 18.791, P0.05). At 2 wk after the treatments, the grades of group B2 were significantly lower than that of groups B3 and B4 (H = 4.025, P0.05 for B2 vs B3; H = 4.361, P0.05 for B2 vs B4). At 4 wk, there were no significant differences of the grades between groups B2, B3 and B4. Regarding pathological changes: Inflammatory cell infiltration and fibroplastic proliferation were observed in the local treated serous membranes, which was the mildest in group B1. Slight foreign-body giant cell reactions were also found in groups B2, B3, and B4.(1) Chitosan gel has preventive effect on traumatic or ischemic peritoneal adhesion, but no obvious effect on foreign body-induced peritoneal adhesion. (2) Chitosan film may exacerbate the peritoneal adhesion. Blending with gelatin to chitosan film can accelerate the degradation of the film, but can simultaneously facilitate the formation of peritoneal adhesion.