Objective To study the advances in microcirculation after islets of Langerhans transplantation (ILT). Methods The literature in the recent years on the study of the relationship between ILT and microcirculation was reviewed. Results The process of angiogenesis and revascularization of the islet grafts was in progress within 1 week after transplantation, and was completed within 10-14 days after transplantation, exhibiting a microangioarchitecture similar to pancreatic islets in situ. The sequence of vascular intraislet cellular perfusion was from β cells outward to α-and δ-cell cortex, with the majority of α cells perfused before the majority of δ cells. Freely transplanted islet grafts were revascularized from the hostderived microvascular bed. The interstitial pressure in the islet transplants was markedly lower than the capillary pressure. There were clearly differences in microcirculation between syngeneic and xenogeneic islet grafts. The phenomena of microcirculation failure were observed in xenografts. The influential factors of microcirculation after ILT were ①culture temperature of isolated islets, ②cultured time and cryopreserved method of islets, ③blood glucose, ④immunosuppressive agents, ⑤angiogenesis factors. Conclusion Microvascularization of freely islet grafts is one of the essential requirements for successful engraftment, guaranteeing sufficient nutritional blood supply to the tissue and establishing blood drainage for adequate liberation of the endocrine hormones. Through the studies of the microcirculation after ILT, it is helpful to recognize the mechanism of the survival of islet grafts.
【Abstract】Objective To study the change of pancreatic microcirculation in the early phase of acute pancreatitis. MethodsLiteratures on acute pancreatitis and microcirculation were collected and reviewed.ResultsPancreatic microcirculation has changed in the early phase of acute pancreatitis, including contraction of interlobular arteriole, slowing of blood fluid, increasing of pancreatic vascular permeability, leukocyte adherence in postcapillary venules, and decreasing of pancreatic perfusion.Conclusion Impairment of pancreatic microcirculation in the early phase of acute pancreatitis may play a key role in the progression of this disease.
In order to investigate the survival mechanism and the role of venous drainage in arterialized venous skin flap, 60 rabbits’ ears were used for research and clinical application of the flap was performed subsequently in two cases. The rabbits were divided into 4 groups. Experimental group was standard arterialized venous skin flap, control 1 group was venous skin flap, control 2 group was arterialized venous skin flap with only one drainage vein and control 3 group was normal skin flap. The process of survival of the flaps was observed by hemodynamic and histological method. The results showed that there was no significant difference between standard arterialized venous skin flap and normal skin flap (P gt; 0.01). Two cases of arterialized venous skin flap survived completely. The conclusion were as follow: 1. the opening of collateral circulation between the veinlets was the main change of the microcirculation; 2. the blood flow of the graft was changed from unphysiological circulation to physiological circulation as the time elapsed and 3. amelioration of venous drainage was important in inproving the survival rate of arterialized vein graft.
【Abstract】 Objective To investigate the angiogenesis in hypertropic scar tissue of rabbit ears at different periods and to explore a new method to prevent hyperplastic scar. Methods Nineteen Japanese white rabbits(weigthing 2.0-2.5 kg) were made animal models of hypertropic scar of ear. At 10th, 30th, 60th and 90 days, after epithel ization, the microvessel and microcirculation in hyperplastic scar of 8 rabbits were studied by microcirculation microscope and laser Doppler flowmetry. The other 11 rabbits’ right or left ears were randomly chosen into experimental group and control group. At 10 days after epithel ization,40 μL of adenovirus extracellular protein with metalloprotease and thrombospondin 1 domains (Ad-METH1) was injected into tissue of scar along the perimeter of the scar in experimental group. The same volume of empty adenovirus was injected in control group. After 30 days of injection, the gross appearance of 10 rabbits’ ears scar was recorded, the number of microvessel in scarwas counted and HE stainning of scar tissue was performed in experimental and control groups. One additional rabbit was used to evaluate the mRNA and protein expression of METH1 by RT-PCR and Western blot after 3 days of injection. R e sults The average number of microvessel at 10, 30, 60 and 90 days after epithel ization was 42.37 ± 3.89, 49.46 ± 4.13, 33.12± 4.34 and 13.24 ±2.31, respectively; the average value of microcirculatory perfusion at 10, 30, 60 and 90 days after epithetl ization was (37.75 ±2.11), (59.87 ± 6.46), (44.53 ± 6.14) and (29.21 ± 1.84)PU; the density of microvessels and perfusion of microcirculation in scar tissues during prol iferative stage (from 10 to 60 days after epithel ization) were markedly higher than that during mature period (90 days after epithel ization, P lt; 0.05).At 10 to 30 days after epithel ization, the histol igical features of scar showed early stage of prol iferation and prol iferative stage appearance; at 60 days after epithel ization, it is still in prol iferative stage, while some of scars were in mature phase; at 90 days after epithel ization, the histol igical features of scar were mature period appearance. At 3 days after Ad-METH1 injection, METH1 gene was successfully expressed at both mRNA and protein levels in experimental group, but not in control group. At 30 days after injection, the gross appearanceobservation showed that scars in experimental group were flat and soft with the color close to normal, but scars incontrol group were obvious and hard. The number of microvessel of scar tissue was 12.38±2.56 in experimental group and 48.12±6.46 in control group, showing statistically significant difference between two groups(P lt; 0.01). In experimental group, HE staining shows that the density of microvessel and the number of fibroblasts were greatly decreased and collagen fibers arranged regularly. In control group, plenty of fibroblasts and abundant microvessels were observed. Thick and tight collagen fibers were seen in the outer layer of dermis with a irregular arrangement. Conclusion Theanti-angiogenesis by Ad-METH1 may have a promising appl ication in the prevention of human hyperthropic scar.
Objective To assess the efficacy and safety of Hirudoid for microcirculation disorder. Methods We searched The Cochrane Library (Issue 4, 2009), PubMed, EMbase, CNKI, CBM, and VIP databases up to December 2009. Randomized controlled trials (RCTs) or quasi-RCTs concerning Hirudoid for microcirculation disorder were included. The methodological quality of the included studies was assessed according to the Cochrane Reviewer’s Handbook 5.0.1, and meta-analyses were conducted using RevMan software 5.0. Results Twenty-five RCTs were included, of which only one was graded as high quality and others were of low quality. The results of meta-analyses showed: Hirudoid could be effective in preventing the occurrence of phlebitis (OR=0.18, 95%CI 0.13 to 0.25). Hirudoid for treating phlebitis was also significantly better than magnesium sulfate or placebo (OR=7.18, 95%CI 4.59 to 11.22) and the time to symptom relief of Hirudoid was significantly shorter than placebo (MD= – 29, 95%CI – 37.30 to – 20.70). Hirudoid for internal fistula in hemodialysis patients was better than the simple hot compress (OR=8.89, 95%CI 4.25 to 18.58), and also better than the magnesium sulfate plus hot compress (OR=7.62, 95%CI 2.84 to 20.44). Hirudoid could also prevent the formation of hematoma and eliminate hematoma quickly. Hirudoid for tissue injury caused by irritating fluid extravasation was significantly better than magnesium sulfate (OR=4.25, 95%CI 2.06 to 8.78). Conclusion Hirudoid can significantly improve the microcirculation disorder, especially to the phlebitis. Due to the low quality of the included studies, further, more high quality trials are required.
The model of acut hemorrhagic necrotizing pancreatitis(AHNP)was produced by retrograde injection of 3% sodium taurocholate into the biliopancreatic duct.48rats with AHNP were treated with Tanshin by subcutaneous injection(100mg/100g body weight,q12h,tanshin group),48 rats with AHNP without any treatment as control(control group).The resule showed that in the control group,there were severe hemorrhage,necroses and the lesions of microvascular,the activity of pancreatic enzyme in serum increased significantly(Plt;0.01)at 6h,after 12h the activities of those pancreatic enzymes decreased gradually, the lesions of microvascular and histology were becoming severer.In the Tanshin group,at 24h the lesions of microvascular and histology of the pancreas were modified significantly (Plt;0.05).These results suggest that the lesion of microcirculation play an important role in the later AHNP,and Tanshin has some effects on the AHNP by modifying the microcirculation of the pancreas.
ObjectiveTo explore the effects of urinastatin(UTI) on microcirculation of extrapancreatic organs in rats with acute necrotizing pancreatitis(ANP). Methods A total of 48 rats were randomized into control group, ANP group and UTI group. The model of ANP was established by uniform injection of 5% sodium taurocholate solution under pancreatic capsule, only injection of normal saline in control group. Then the rats of UTI group were injected with UTI through the femoral vein, the rats of ANP group and control group were injected with normal saline. The blood flow of lung, kidney and distal small intestine was measured by radioactive biomicrosphere technique at 2 h and 6 h after ANP.ResultsCompared with the control group, the blood flow of lung, kidney and intestine was decreased significantly in the ANP group at the 2 h and 6 h after ANP （P＜0.05）, compared with the ANP group, the blood flow was increased significantly in UTI group （P＜0.05）. ConclusionMicrocirculation disorder is an important factor of the extrapancreatic organ damage in ANP, and UTI plays a protective role against microcirculation disorder of the extrapancreatic organ in ANP.
Objective To investigate the relationship between gene expression of endothelin-3 (ET-3） and inflammation of acute pancreatitis （AP） in rats. Methods Fifty-four rats were divided randomly into 4 groups: sham operation group, AP group, arterial injection group and vein injection group. AP was induced by reverse intra-bile duct infusion 4.5% sodium taurocholate, treated with low dose dopamine 〔5 μg/（kg·min）〕 by injecting arterial or tail vein. Rats were sacrificed at 1， 6 and 24 h after the induction of AP. The mRNA expression of ET-3 was evaluated by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and pathological changes was observed in rats. Results Expression of ET-3 mRNA could be detected from 1 up to 24 h after the induction of pancreatitis. Expression of ET-3 mRNA of sham operation group was decreased significantly compared with other three groups. Expression of ET-3 mRNA showed a significant decrease by arterial injection dopamine than that by tail vein (P＜0.05， P＜0.01). The pathologic score in AP group was the highest, vein injection group was the next one, and score in sham operation group was the lowest. Conclusion There are significant relationship between inflammation of AP and expression of ET-3 mRNA. Dopamine administration by arterial injection is more effective than that by tail vein injection.
Objective To explore the effect of renal microcirculation following severity acute pancreatitis （SAP） on renal injury and to explore the protection effect of urokinase on them. Methods A total of 192 Wistar rats were randomized divided into normal control group， SAP group， and urokinase group， then rats of 3 groups were sub-divided into 2， 6， 12， and 24 hours group， each group enrolled 16 rats. Of the 16 rats in each subgroup， 8 rats underwent blood flow of renal test， other 8 rats were sacrificed to get blood samples and to perform histopathological examination. The rat models of SAP were established by retrograde injecting with 5% sodium taurocholate into the cholangiopancreatic duct. Radioactive biomicrosphere technique was used to measure the blood flow of renal， levels of plasma thromboxane B2（TXB2） and 6-keto-prostaglandin F1α （6-Keto-PGF1α） were tested by the TXB2 kit and 6-Keto-PGF1α kit， and histopa-thological changes of renal tissues were observed by using HE staining. Results Compared with normal control group at the same time point， the blood flow of renal were lower （P＜0.05）， activity ratio of TXB2 to 6-Keto-PGF1α were higher（P＜0.01）， and the histopathological injury were worse （P＜0.01） in rats of SAP group and urokinase group. Compared with SAP group， the blood flow of renal at 2， 6， and 12 hours in urokinase group were higher （P＜0.01）， the activity ratios of TXB2 to 6-Keto-PGF1α were lower （P＜0.01）， and the histopathological injury were lighter （P＜0.05） in all the 4 time points of urokinase group. Conclusions The renal microcirculation dysfunction and increase of activity ratio of TXB2 to 6-Keto-PGF1α may play an important role in renal injury following SAP in early stage. Urokinase can protect the renal from such injuries.
OBJECTIVE: To study the forms of microcirculation of arterialized venous flap. METHODS: Twenty New Zealand rabbits were equally divided into two groups, arterialized venous flap group (group A) and control group (group B). The microcirculatory haemodynamic of arterialized venous flap was studied through observation of transparent chamber in rabbit’s ears with aspecial TV set with manification of 1000. RESULTS: The blood of arterilized venous flap flowed through venule anastomosis and drained to another venule. CONCLUSION: It is the main form of microcirculation in early stage that blood flows from venule to draining venule by way of communicating networks between venules.