Prevention of pleural adhesions using a membrane containing polyethylene glycol in rats

Background: Recurrent thoracotomies regardless of the cause are not a rare occurrence. However, each thoracotomy results in adhesion to some extent. This adhesions increase morbidity and mortality presents a significant inconvenience for surgeons and prolongs the length of operations.Objective: We investigated the efficacy of Prevadh®, an anti-adhesion agent to prevent intrapleural adesions following thoracotomy in a rat model.Methods: Twenty male adult Wistar Albino rats were divided into a sham group (Group A, n = 4), a control group (Group B, n = 8), and a study group (Group C, n = 8). Only left thoracotomy was performed in Group A. Group B underwent left thoracotomy, induction of adhesion, and 1 ml saline solution was administered to the thoracic cavity. However, in Group C underwent left thoracotomy, induction of adhesion, and Prevadh® was placed between the pleura and the lung. The rats were sacrificed on day 21, and adhesions were analyzed using both macroscopic and histopathological methods. The results were statistically analyzed. A value of P<0.05 was considered statistically significant.Results: Mean lengths of adhesion differed statistically significantly among all three groups, while mean intensity of adhesion differed between Group A and Group B, and between Group B and Group C (P>0.05). There was also a statistically significant difference between Group A and Group C in mesothelium proliferation score (P>0.05). No statistically significant differences were found among the groups in terms of pleural thickness, macrophage and mononuclear cell infiltration (P>0.05).Conclusions: Prevadh® was shown in a rat model to effectively prevent post-thoracotomy adhesions.     

Comparison of Intraperitoneal Honey and Sodium Hyaluronate-Carboxymethylcellulose (Seprafilm™) for the Prevention of Postoperative Intra-Abdominal Adhesions

BACKGROUND:

Abdominal surgery can lead to postoperative intra-abdominal adhesions (PIAAs) with significant morbidity and mortality. This study compares the use of honey with a standard bioresorbable membrane (Seprafilm™) to prevent the formation of PIAAs in rats.

METHODS:

Thirty rats underwent laparotomy, and PIAAs were induced by scraping the cecum. The animals were divided into three groups, each containing ten rats. Group 1 (control) represented the cecal abrasion group, with no intraperitoneal administration of any substance. Group 2 (honey group) underwent cecal abrasion and intraperitoneal administration of honey. Group 3 (Seprafilm™ group) underwent cecal abrasion and intraperitoneal Seprafilm™ application.

RESULTS:

Group 1 exhibited higher adhesion scores for adhesions between the abdominal wall and the organs. Groups 2 and 3 had decreased adhesive attachments to the intra-abdominal structures. Compared to group 1, the incidence of adhesion formation was lower in both group 2 (p=0.001) and group 3 (p=0.001). The incidence of fibrosis was also lower in group 2 (p=0.016) and group 3 (p=0.063) compared to group 1. There was no significant difference between the histopathological fibrosis scores for the rats in group 2 and those in group 3 (p= 0.688).

CONCLUSION:

This study suggests that both honey and Seprafilm™ decrease the incidence of PIAAs in the rat cecal abrasion model. Although the mechanism of action is not clear, intraperitoneal administration of honey reduced PIAAs. The outcome of this study demonstrates that honey is as effective as Seprafilm™ in preventing PIAAs.     

Dexamethasone and sodium carboxymethyl cellulose prevent postoperative intraperitoneal adhesions in rats

We aimed to evaluate the effects of the barrier agent sodium carboxymethyl cellulose (SCMC) with and without dexamethasone for the prevention of postoperative adhesion formation in a rat model of postoperative peritoneal adhesion. A total of 160 three-month old male and female Wistar rats underwent a laparotomy, and adhesions were induced by ileocecal abrasion. Rats were randomly assigned to 4 groups (n=40 each): group A, untreated; group B, treated with SCMC only; group C1, treated with SCMC + 3 mg dexamethasone, and group C2, treated with SCMC + 8 mg dexamethasone. After 12 days, adhesion formation and histopathological changes were compared. In groups A, B, C1, and C2, the mortality rates were 10, 5, 5, and 5%, respectively. In groups C1 and C2, the adhesions were filmy and easy to dissect and were milder compared with those in groups A and B. The total adhesion score in group C1 (3.38±0.49) was significantly lower than that of group B (6.01±0.57; P<0.01) or group A (8.01±0.67; P<0.05). There was no significant difference in adhesion formation between groups C1 and C2. Compared with groups A and B, groups C1 and C2 exhibited milder histopathological changes. SCMC in combination with dexamethasone can prevent adhesion formation and is a better barrier agent than SCMC alone. The safety and feasibility of SCMC in combination with dexamethasone to prevent adhesion formation after abdominal surgery warrants further clinical study.     

Effect of Hypericum perforatum on intraperitoneal adhesion formation in rats

Introduction

The aim of this study was to evaluate the efficacy of Hypericum perforatum for prevention of adhesion formation in rats.

Material and methods

Twenty-four female wistar rats underwent left uterine horn adhesion model. Rats were randomised into 4 groups. Group 1 (Control): Closure of abdominal incision without any agent administration. Group 2: Closure of incision after administration of intraperitoneal (i.p.) Ringer''s lactate solution. Group 3: Closure of incision after administration of i.p. olive oil (diluent of H. perforatum). Group 4: Hypericum perforatum extract (Ecodab^®) was administered i.p. before the closure of incision. Fourteen days later, relaparatomy was performed and surgical adhesion scores, inflammation and fibrosis scores were noted. Groups were compared according to these scores.

Results

There was statistical significant difference between ringer''s lactate group and olive oil group according to surgical adhesion score (p = 0.009). However, groups were not different according to inflammation and fibrosis scores (p > 0.05).

Conclusions

Despite antiinflammatory, antioxidants and antimicrobial properties of H. perforatum, our results revealed no positive effect of H. perforatum on the prevention of intraperitoneal adhesion formation.     

Comparison of hyaluronate/carboxymethylcellulose membrane and melatonin for prevention of adhesion formation in a rat model

BACKGROUND: To investigate the effectiveness of melatonin in preventing post-operative adhesion formation and to compare it with the efficacy of hyaluronate/carboxymethylcellulose membrane in a rat model. MATERIALS and METHODS: Following pilot studies, 35 rats were operated on in the full study. In 15 animals (group one), 10 standard lesions were inflicted in each uterine horn (total 30 horns) and melatonin was applied before closure of the abdomen. In the second group, 20 animals were operated on and one of the uterine horns (total 20 horns) with standard lesions was treated with hyaluronate/carboxymethylcellulose membrane and the other uterine horn served as a control. Second-look operations were performed 1 week later and adhesion scores were compared. RESULTS: The adhesion scores of uterine horns treated with melatonin and of uterine horns treated with hyaluronate/carboxymethylcellulose membrane were significantly lower than the scores of the controls (P < 0.001). There was no statistically significant difference between the adhesion scores of uterine horns treated with melatonin and of uterine horns treated with hyaluronate/carboxymethylcellulose membrane (P > 0.05). CONCLUSIONS: Both melatonin and hyaluronate/carboxymethylcellulose membrane were effective in prevention of adhesion formation in a rat uterine horn model.     

The effect of high dose melatonin on cardiac ischemia- reperfusion Injury

Purpose

Melatonin, the most potent scavenger of toxic free radicals, has been found to be effective in protecting against pathological states due to the release of reactive oxygen species. This study was performed to establish the effect of high dose melatonin on protection against ischemia-reperfusion (I/R) injury in rat hearts.

Materials and Methods

Forty male Sprague-Dawley rats were used in this study. They were separated into four groups of ten rats each. A left coronary artery occlusion was induced in the rats by ligating the artery for 20 minutes and then releasing the ligation (reperfusion) afterwards. The control group was Group A. Group B was subjected to myocardial ischemia-reperfusion without any treatment, while Group C underwent myocardial ischemia-reperfusion with a melatonin treatment before the ischemia. Group D was subjected to myocardial ischemia-reperfusion with a melatonin treatment before the reperfusion. After 20 minutes of reperfusion, blood samples were obtained from each group for biochemical studies, and the animals were sacrificed for histological and, immunohistochemical examinations of the myocardial tissue.

Results

We found that the cardiac troponin T(cTn-T) levels were significantly increased in Group B when all groups were compared. In the Group C rats treated with melatonin, the cTn-T values were significantly lower than those in Groups B and D. In addition, malondialdehyde (MDA) and antioxidant enzymes including, superoxide dismutase (SOD) and myeloperoxidase (MPO) were lower than those in Group B in the melatonin treated groups. The differences were statistically significant (p < 0.05). Histopathologic and immunohistopathologic studies also supported the effectiveness of melatonin.

Conclusion

Our study suggests that high dose melatonin, appears to offer protection against cardiac ischemia-reperfusion injuries in rats by scavenging the free radicals and could have a potential clinical use in the management of myocardial ischemia.     

Impairment of the Peritoneal Surface as a Decisive Factor for Intestinal Adhesions in Intraperitoneal Onlay Mesh Surgery - Introducing a New Rat Model

Background: Meshes implanted intraperitoneally are known to cause adhesions potentially resulting in complications such as chronic pain, enterocutaneous fistula, or mesh infection. This study introduces a model for investigation of intestine-to-mesh adhesions and evaluates as to whether missing of visceral peritoneum is causative.Methods: In 18 rats, rectangular 1.5 x 2 cm patches of an uncoated polypropylene mesh (Ultrapro^®) were sewn to the inner abdominal wall next to the cecum. Additionally, a meso-suture ensured contact between cecum and mesh. Rats were assigned to 2 groups: in 8 rats the peritoneum was left intact, in 10 the cecum was depleted from peritoneum with abrasion. Sacrifice was on day 7. Macroscopic evaluation used two adhesion scores. Specimens were evaluated microscopically, statistical analyses employed student''s t-test.Results: On day 7, rats with mesh implantation combined with locally de-peritonealization by cecal abrasion mostly showed severe cecum-to-mesh agglutination (mean Lauder score 92%, mean total Hoffmann score 90%), whereas meshes of most animals without cecal abrasion only had some coverage with intraabdominal fat (33%, 24%; p = 0.0002). Histological work-up showed adequate wall ingrowth of mesh in all rats. In animals with cecal abrasion, meshes were mostly adhesive with cecal wall. However, when the peritoneum of cecum was unimpaired, abdominal wall above the mesh as well as cecum usually revealed sub-peritoneal tissue and a mono-layer cell coverage as seen in normal peritoneum.Conclusion: This study introduces a model mimicking a clinical situation of e.g. hernia repair by intraperitoneally implanted meshes when mesh has contact with normal and with de-peritonealized intestine. The model might be useful for testing mesh types and coatings as well as other devices for their efficacy in adhesion prevention. The high adhesion scores of rats with local de-peritonealization compared with the low scores of animals with intact peritoneum indicate that the integrity of intestinal peritoneum is a decisive factor for adhesion formation.     

Effects of oral administration of Phyllanthus amarus leaf extract on the kidneys of adult wistar rats: a histological study

Histological studies of the effects of oral administration of aqueous extract of Phyllanthus amarus commonly used in ethno medical practice in Africa for the management of various ailments such as kidney stones, dysentery, jaundice, diarrhoea and urogenital diseases on the kidney of adult Wistar rats were carefully studied. Rats of both sexes (n=24), average weight of 260g were randomly assigned into three groups: A, B and C of (n=8) in each group. Group A and B served as treatment groups (n=16) while group C (n=8) served as the control. The rats in the treatment groups (A & B) received 500mg/kg and 1000mg/kg body weight respectively of aqueous extract of Phyllanthus amarus orally through orogastric tube for twenty-eight days, while the control rats received equal volume of distilled water without the extract of Phyllanthus amarus added for the same period. The rats were fed with growers' mash purchased from Edo feeds and Flour Mill Ltd, Ewu, Edo state and were given water liberally. The rats were sacrificed on day twenty-nine of the experiment. The kidneys were carefully dissected out and quickly fixed in 10% formal saline for routine histological study after H&E method. The histological findings indicated that the treated sections of the kidneys showed hypertrophy of blood vessels, mild-severe infiltrate of chronic inflammatory cells and varying degrees of tubular necrosis when compared to the control sections. The findings indicated that the administration of Phyllanthus amarus extract has some adverse effects on the kidneys of adult Wistar rats. It is recommended that further studies aimed at corroborating these observations be carried out.     

Oral tadalafil reduces intra-abdominal adhesion reformation in rats

BACKGOUND: Currently, there is no ideal agent to prevent adhesion formation. We have shown that sildenafil, a phosphodiesterase-5 (PDE-5) inhibitor, reduces post-operative adhesion formation by vasodilatation and increases fibrinolytic activity. Here, we evaluated whether tadalafil, a long-acting PDE-5 inhibitor, decreases post-operative adhesion reformation in rats. MATERIALS AND METHODS: Standardized lesions were created in Wistar albino rats by cauterization of uterine horns and abrasion of adjacent peritonium. The extent and severity of adhesions were scored on the 14th post-operative day and adhesiolysis was performed at the second laparotomy. Animals were then assigned randomly into two groups. The study group (n = 11) received 10 mg/kg oral tadalafil by gavage 60 min before the second laparotomy and daily for 14 days afterwards. Controls (n = 11) received the same volume of tap water for 14 days by gavage. Animals were killed 15 days after adhesiolysis and adhesions were scored blind during the third laparotomy. RESULTS Basal adhesion scores at the time of the second laparotomy were comparable in the study and control groups. Scores for the extent of adhesion reformation in the study and control groups did not differ [median 1 (range 0-3) versus median 2 (range 1-3); P: 0.81] but tadalafil reduced the respective severity scores [median 0.5 (range 0-1) versus median 1 (range 0.5-1); P: 0.02] and total scores [median 2 (range 0-4) versus median 2.5 (range 1.5-4); P: 0.042]. CONCLUSIONS: Oral administration of tadalafil during the perioperative period reduces intra-abdominal adhesion reformation in rats.     

微血栓大鼠循环内皮细胞,血浆内皮素和一氧化氮测定的结果分析

目的：对微血栓动物模型行普通肝素和低分子量肝素的治疗，通过内皮细胞计数（CEC）、内皮素（ET）、一氧化氮（NO）三项指标观察分析其血管内皮细胞损害及肝素的治疗效果。方法：对18只wistar大鼠行尾静脉注射高分子右旋糖苷（高右），制成微血栓动物模型。其中12只在高右基础上分别予普通肝素（普肝组，n＝6）和低分子量肝素（低肝组，n＝6）治疗。其余6只不治疗。另以5只wistar大鼠行尾静脉注射生理盐水为正常对照组（对照组，n＝5）。对上述各组作循环内皮细胞计数（CEC）、血浆内皮素（ET）及一氧化氮（NO）测定。结果：高右组CEC、ET高于对照组和治疗组（P＜0．05），NO则低于对照组和治疗组（P＜0．05）。治疗组的上述结果均有明显恢复至对照组的趋势。结论：微血栓大鼠有血管内皮损伤，普通肝素及低分子量肝素不仅能抗微血栓形成，且可促进血管内皮细胞功能恢复，其中以低分子量肝素为优。     

Effects of supplemental perioperative oxygen on post-operative abdominal wound adhesions in a mouse laparotomy model with controlled respiratory support

BACKGROUND: Post-operative adhesion formation is a major clinical problem. Tissue oxygenation is one of the most important determinants in adhesion formation. The objective of this study was to investigate whether supplemental perioperative oxygen could reduce post-operative adhesion formation through increasing the peritoneal tissue oxygen tension (PitO(2)) in a mouse model. METHODS: Adult C57BJ6 mice were randomly assigned to two groups: Group 1 (n = 20), Fraction of Inspired Oxygen (FiO(2)): 0.21; Group 2 (n = 20), FiO(2): 0.80. On day 0, over the course of the 90 min procedure including the 60 min of laparotomy, PitO(2) was continuously monitored. On day 7, a second laparotomy was performed to assess abdominal wound adhesions. Real-time RT-PCR was performed to measure expression levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) mRNA in peritoneal tissues. RESULTS: The PitO(2) levels in Group 2 were significantly higher compared to Group 1 (P < 0.001) and controls (P < 0.003). There was no significant difference in the incidence of abdominal wound adhesions; however, the severity of adhesions was significantly reduced in Group 2 compared to Group 1 (P < 0.03). A significantly higher tPA/PAI-1 mRNA ratio was detected in Group 2 and the controls compared to Group 1 (P < 0.02 and P < 0.002, respectively). CONCLUSIONS: Supplemental perioperative oxygen may help to reduce post-operative adhesion formation.     

功能性消化不良患者伴抑郁障碍的诊断和治疗

目的：探讨功能性不良（FD）患者的抑郁障碍及抗抑郁药对其疗效。方法：以CCMD－2－R为标准诊断抑郁障碍。将伴抑郁的FD随机分为3组：文拉法新组，多塞平组和对照组（常规内科治疗）。以治疗前，治疗2周和8周FD症状积分及Zung抑郁自评量表（SDS）积分变化评定疗效。结果：（1）FD中抑郁障碍的发生率为32．28％。（2）FD症状积分在文拉法新组和多塞平组于治疗2周时即明显减少（P＜0．05），于治疗8周时非常明显低于对照组（P＜0．05）；SDS只分在文拉法新组于治疗2周时即明显减少（P＜0．05），文拉法新组和多塞平组于治疗8周时均明显低于对照组（P＜0．05）；（3）文拉法新组不良反应明显低于多塞平组。结论：FD伴发的抑郁障碍发生率高，抗抑郁治疗能有效改善消化不良和抑郁症状，文拉法新作用迅速且优于多塞平。     

Mouse embryos generated from frozen-thawed oocytes can successfully survive a second cryopreservation

BACKGROUND: To determine whether mouse embryos generated from frozen-thawed oocytes can successfully survive a second cryopreservation. METHODS: Immature C57BL6*BALB/c female mice underwent superovulation and the collected oocytes were divided into three groups. Group A oocytes (n = 107) underwent IVF. Group B oocytes (n = 167) underwent IVF and embryos generated were then cryopreserved. Group C oocytes (n = 94) were cryopreserved, thawed and underwent IVF. Two-four-cell stage embryos were re-cryopreserved and thawed. Embryos from all groups were then cultured to the blastocyst stage. RESULTS: Cleavage rates to the 2-4-cell stage were 78, 71 and 46% for groups A, B and C respectively. Blastulation rates from 2-4 cell-stage embryos were 37/83 (45%), 27/118 (23%) and 8/35 (23%) for groups A, B and C respectively. Development to blastocysts was observed in 37/107 oocytes (35%), 27/167 oocytes (16%) and only 8/94 oocytes (9%) for groups A, B and C respectively. CONCLUSION: Oocyte cryopreservation results in reduced fertilization rates. Embryo cryopreservation reduces blastulation rates by half regardless of whether the oocytes were fertilized fresh or frozen-thawed. Nevertheless, embryos generated from cryopreserved oocytes can survive cryopreservation and develop to the blastocyst stage at rates comparable with embryos obtained from fresh oocytes.     

凝血和纤溶相关指标对判断AP病情和预后的意义

目的：探讨凝血、纤溶相关指标对判断急性胰腺炎（AP）病情和预后的意义。方法：将99例AP患者依病情分为A、B、C、D四组。回顾性分析四组患者血小板计数（PLT）、凝血酶原时间（PT）、活化部分凝血酶时间（APTT）、纤维蛋白原（FIB）、D二聚体（D-D）水平与临床表现及预后的关系。结果：A组、B组比较,PLT、PT、FIB、D-D四项指标差异明显（P〈0.05或P〈0.01）;B组、C组比较,APTT一项存在差异（P〈0.01）;C组、D组比较,PLT、PT、APTT、FIB、D-D五项指标均存在明显差异（P〈0.05或P〈0.01）。从A组到D组,各项检测指标逐渐恶化。结论：PLT、PT、APTT、FIB、D-D的含量变化,与AP严重程度及预后密切相关;临床可以通过检测PLT、PT、APTT、FIB、D-D的含量,作为判断AP严重程度和估计预后的重要指标。     

Protection of Chinese Herbs Against Adenine-Induced Chronic Renal Failure in Rats

The aim of the study is to evaluate the efficacy of Chinese herbs (Angelica sinensis, Ligusticum wallichii, Salvia miltiorrhiza, Rhizoma dioscoreae, Rhodiola crenilata, Astragalus membranaceus and Angelica sinensis) on adenine-induced chronic renal failure in rats. 30 age-matched male Wistar rats were divided into three groups. Rats in group A (n=10), B (n=10) and C (n=10) were fed a standard laboratory chow and allowed tap water ad libitum. In group B and C, renal failure was induced by the administration of a diet containing 0.75% adenine for 28 days which began at day 0. Rats in group C were given Chinese herbs (40ml/kg with drug concentration 1.75g/ml) beginning at day 0. Urine albumin, blood urea nitrogen (BUN) and creatinine were determined at days 0, 14 and 28. At day 28, the animals were killed and their kidneys removed for light microscope evaluation. Body weight in Group B decreased more significantly than that in Group C (p=0.032) at day 28. The rats in group B demonstrated more severe proteinuria and higher Serum creatinine and BUN levels than group C at day 14 and day 28 (P<0.05, 0.01). All rats given adenine developed marked structural renal damage involving the tubule and interstitium. The values were much less severe in group C than those in group B. In adenine-induced chronic renal failure rats, the protective effects of these Chinese herbs were of a significant nature. Our results do support the notion that these Chinese herbs are useful in deferring the advance of chronic renal failure. We recommend Chinese herbs as a beneficial treatment for pre-end stage chronic renal failure.Key words: Chinese herbs, Adenine, Renal failure, Histology     

The neuroprotective effects of caffeic acid phenethyl ester (CAPE) in the hippocampal formation of cigarette smoke exposed rabbits

BACKGROUND: In this study, the neuroprotective effects of caffeic acid phenethyl ester (CAPE) in the hippocampus of cigarette smoke exposed rabbits were investigated. MATERIALS AND METHODS: Eighteen rabbits were used as experimental subjects and divided into three equal groups. The control group (Group A) was exposed to clean air. Rabbits in the cigarette smoke (CS) group (Group B) were exposed to cigarette smoke 1 hour daily in a room within a glass chamber for 4 weeks. Animals in the CS+CAPE group (Group C) were exposed to cigarette smoke as in Group B and administered CAPE (10 micromol/kg/day) intraperitoneally for 4 weeks just before the exposure to cigarette smoke. Rabbits in all three groups were sacrificed with intraperitoneal administration of 100 mg/kg sodium pentothal and their brains were removed immediately. In the hippocampal formation samples of left hemispheres, the levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured and the number of apoptotic neurons was counted by 'terminal transferase dUTP nick end labelling' (TUNEL) assay in the right hippocampal formation. RESULTS: We found that MDA levels increased significantly in the Group B rabbits compared with the control group (Group A; p = 0.001). In contrast, SOD activities decreased significantly in Group B rabbits compared with the control group (p = 0.001). In the CAPE treated rabbits (Group C), MDA levels decreased and SOD activities increased significantly as compared with Group B rabbits (p = 0.002, p = 0.002, respectively). The number of apoptotic neurons (TUNEL+) in the CA1, CA2, CA3 and dentate gyrus areas of rabbits' hippocampal formation were significantly increased in Group B rabbits compared with the control group. On the other hand, the number of apoptotic neurons in the hippocampus areas was decreased significantly in Group C rabbits compared with Group B rabbits. CONCLUSION: These findings suggest that cigarette smoking induces apoptosis in the hippocampal formation of rabbits and CAPE has a protective role against this induction.     

The ameliorating effect of exogenous melatonin on urinary bladder function in hyperosmolar bladder overactivity and its influence on the autonomic nervous system activity

This study was designed to investigate the effects of melatonin on the bladder hyperactivity in hyperosmolar-induced overactive bladder (OAB) rats. Additionally, the influence of melatonin on the autonomic nervous system (ANS) using heart rate variability (HRV) analysis was assessed. 40 rats were divided into four groups: I--control (n = 12), II--rats with hyperosmolar OAB (n = 6), III--rats with melatonin pretreatment and hyperosmolar OAB (n = 6) and IV--control with melatonin pretreatment (n = 6). In group III and IV melatonin in dose of 100 mg/kg was given. HRV measurements in 10 rats, as follow: control (n = 2), control after melatonin treatment (n = 2), rats with hyperosmolar OAB without (n = 3), and after (n = 3) melatonin treatment were conducted. This study demonstrates marked influence of melatonin on urinary bladder activity in hyperosmolar-induced OAB rats. These rats showed significantly reduced the detrusor motor overactivity resulting in the improvement of cystometric parameters after melatonin treatment when compared to the control, as follow: a significant increase of intercontraction interval (70%) and functional bladder capacity (67%), as well as a decrease of the basal pressure, detrusor overactivity index and motility index of 96%, 439% and 40%, respectively. ANS activity analysis revealed sympathetic overactivity in OAB rats, and parasympathetic superiority in melatonin treated OAB rats. Melatonin treatment in rats with hyperosmolar OAB (group III) caused significant increase of nuHF parameter (from 51.00 +/- 25.29 to 76.97 +/- 17.43), as well as a decrease of nuLF parameter (from 49.01 +/- 25.26 to 23.03 +/- 17.43) and LF/HF ratio (from 1.280 +/- 0.980 to 0.350 +/- 0.330). In conclusion, melatonin suppresses hyperosmolar OAB, and modulates ANS activity by inhibition of the sympathetic drive. Therefore, melatonin may become a useful agent for OAB management.     

肌酸对帕金森病模型大鼠黑质多巴胺能神经元保护作用的研究

目的:观察肌酸对帕金森病模型大鼠黑质多巴胺能神经元的保护作用及其机制。方法:30只雄性SD大鼠随机分成3组:对照组(A组),6-羟多巴胺(6-OHDA)组(B组),肌酸+6-OHDA组(C组),每组各10只。A组不注射6-OHDA,B组进行6-OHDA造模,C组在造模前5天每天给予肌酸(100 mg/kg)灌胃,连续两周,B组给予生理盐水4 ml灌胃。分别观察各组动物行为学、黑质多巴胺能神经元数量及氧化应激指标谷胱甘肽(GSH)和丙二醛(MDA)水平变化。结果:6-OHDA立体定向注射后,实验大鼠出现阿朴吗啡诱导的旋转行为,黑质致密部多巴胺能神经元显著减少,GSH含量降低、MDA水平升高;肌酸能够减轻动物行为学异常(P0.01)、显著增加黑质致密部多巴胺神经元数量(P0.01),拮抗6-OHDA诱导的氧化应激水平升高(P0.01)。结论:肌酸对6-OHDA诱导的多巴胺神经元损伤具有明显保护作用,其机制与抑制氧化应激损伤有关。     

The effects of ghrelin on colonic anastomosis healing in rats

OBJECTIVES:

In addition to its roles in the stimulation of growth hormone secretion and the regulation of appetite and metabolism, ghrelin exerts immunomodulatory, anti-inflammatory and antioxidant actions in several organ systems. In this study, we investigated the effects of ghrelin on the healing of experimental colonic anastomoses.

METHODS:

Wistar rats were randomly divided into two groups (n = 10 in each). A segment of colon was excised, and an end-to-end anastomosis was performed in the distal colon. The Ghrelin Group received 10 ng/kg/day IP ghrelin for seven days postoperatively, whereas the Control Group received an identical volume of saline. On the seventh postoperative day, the anastomotic bursting pressures and hydroxyproline levels were measured, and adhesion formation around the anastomoses was examined. Histopathological analyses were performed to evaluate inflammatory cell infiltration, fibroblast infiltration, collagen density and neovascularization.

RESULTS:

In the Ghrelin Group, the bursting pressure and hydroxyproline levels were significantly higher than in the Control Group. The adhesion formation scores were lower in the Ghrelin Group than in the Control Group. Although the inflammatory cell infiltration was diminished in the Ghrelin Group, the degrees of fibroblast infiltration, collagen density and neovascularization were not significantly different between the groups.

CONCLUSION:

Our results indicate that ghrelin improves the healing of colonic anastomoses in rats.     

Effects of leptin on femoral fracture in rats

In this study, our objective was to evaluate effects of leptin on fracture healing in rats. Seventy two male SpragueDawley (SD) rats were randomized into 3 groups. Standardized femoral fractures were created in all the rats. Group A was treated with 1 mL normal saline (NS), group B with 0.3 μg/kg leptin in 1 mL NS, and group C with 0.5 μg/kg leptin in 1 mL NS for 2 weeks intraperitoneally. Each group was divided into three subgroups including 8 rats for evaluation at 2, 4 and 8 weeks. Radiological evaluation showed that callus formation of group B and C was all significantly higher than group A at 8 weeks (P = 0.04 and P = 0.013, respectively). There was no statistically significant difference in fracture healing between group B and group C at 8 weeks (P = 0.197). Histological evaluation revealed fracture healing of group B and C was better than group A at 4 weeks (P = 0.01 and P = 0.002, respectively) and 8 weeks (P = 0.008 and P = 0.003, respectively). Micro-computed tomography (Micro-CT) analysis demonstrated that greater amounts of bony callus and evidence of bone fusion were observed in group B and C at 4 weeks (P = 0.02 and P = 0.04, respectively) and 8 weeks (P = 0.005 and P = 0.001, respectively) compared to group A. Group C also had better fracture healing than group B at 8 weeks (P = 0.01). In conclusion, leptin has a positive effect on rat femoral fracture healing.