OBJECTIVE:To investigate relationship between plasma endotbelin(ET)and serum angiotensin converting enzyme (ACE)levels and diabetic retinopathy (DR). METHODS: Plasma ET and serum ACE levels were measured in 62 patients with diabetes mellitus(DM) and in 30 normal control subjects with radioimmunoassay and ultraviolet-spectrophotometry. RESULTS:Plasma ET and serum ACE levels in patients with DR were significantly higher than in patients without DR (P＜0.01). Along with the progression of DR,plasma ET levels were significantly elevated and serum ACE levels were gradually elevated. CONCLUSIONS :These findings suggest that increased plasma ET and serum ACE levels may be related to the development and progression of DR. （Chin J Ocul Fundus Dis,1996,12: 177-179）
Objective To investigate the serumlevel of endothelin-1 ( ET-1) in patients with acute lung injury/acute respiratory distress syndrome ( ALI/ARDS) and its clinical significance. Methods Thirty-one ALI/ARDS patients received mechanical ventilation in ICUand 25 normal subjects were recruited in the study. The patients who died in two weeks fell in death group, and the patients who did not died in two weeks fell in survival group. The serum level of ET-1 measured by EIA method were compared between thepatients with different severity of lung injury [ evaluated by American-European Consensus Conference on ARDS ( AECC) criteria and lung injury score( LIS) ] , and between the patients with different prognosis ( death or survival ) . The correlation was analyzed between the level of ET-1 and clinical parameters.Results The ET-1 level was higher in the ALI/ARDS patients than that in the control subjects [ ( 6. 18 ±4. 48) ng/L vs. ( 2. 68 ±1. 34) ng/L, P lt;0. 05] . There was no significant difference in the patients with different severity [ ALI vs. ARDS, ( 5. 43 ±4. 39) ng/L vs. ( 7. 01 ±4. 51) ng/L, P gt; 0. 05; LIS≤2. 5 vs.LISgt;2. 5, ( 5. 93 ±5. 21) ng/L vs. ( 6. 68 ±2. 76) ng/L, P gt; 0. 05] . The ET-1 level in the death group continued to increase, and higher than that in the survival group on the 5th day [ ( 7. 96 ±3. 30) ng/L vs.( 4. 36 ±3. 29) ng/L, P lt; 0. 05] . The ET-1 level was positively correlated with SIRS, SAPSⅡ and APACHEⅡ ( r = 0. 359, 0. 369 and 0. 426, respectively, P lt; 0. 05 ) , and negatively correlated with PaO2 /FiO2 and AaDO2 ( r = - 0. 286 and - 0. 300, respectively, P lt;0. 05) . Conclusion The measurementof serum ET-1 can help to evaluate the severity and prognosis of ALI/ARDS patients.
Objective To study the effects of endothelin (ET) on acute pancreatitis in rats. Methods The acute edematous pancreatitis (AEP) and hemorrhagic necrotizing pancreatitis (AHNP) model of rats were induced by cerulein and dextran-110 and endothelin-1 was administered on AEP rats via intravenous injection. Serum amylase, plasma ET and 6-Keto-PGF1α, pancreas hostologic observation were determined. Results The serum concentration of amylase increased markedly in AHNP rats, and there was a significant difference between AHNP and AEP (Ｐ＜0.01). A dose of extrinsic ET-1 may induce the conversion of AEP to AHNP in rats. The degree of pancreatic damage correlates positively with the level of the plasma ET. Conclusion Endothelin might take part in the development of acute pancreatitis, and play a key role in the conversion of AEP to AHNP.
This prospective animal study was designed to investigate the changes of plasma endothelin (ET) levels in acute necrotizing pancreatitis (ANP). Sprague-Dawley rats were randomly devided into 3 groups: acute necrotizing pancreatitis (ANP) group in which ANP was induced by infusion of 5% sodium taurocholate (STC) into biliopancreatic duct, sham operation (SO) group and platelet activating factor antagonist BN50739 (BN) group. Blood levels of ET and platelet activating factor (PAF) were detected. Pancreatic microcirculatory blood flow was measured and pancreatic histological scores were evaluated. Results showed that the pancreatic microcirculatory blood flow in ANP group was decreased to a great extent immediatly after induction of ANP and soon began to rise slowly for 3 hours and again decreased steadily after that. The blood levels of ET, PAF and histological scores in ANP group were significantly higher than those in SO group. In BN group, the blood flow was significantly improved and the levels of blood ET, PAF and histological scores were all significantly lower as compared to those in ANP group. It is concluded that ischemia/ reperfusion is present in the initiation of acute necrotizing pancreatitis induced by STC in the rat. This leads to injuries of endothelial cells and increase in the production of ET and PAF. I/R lesions,and interaction of ET and PAF lead to a vicious circle, thus augmenting the pathological changes in the pancreas.
Objective To investigate the role of endothelin（ET） in lung injury during cardiopulmonary bypass （CPB） and study the possible mechanism of ET-mediated lung injury and the protective effect of ferulic acid（FA） during the procedure. Methods Twelve dogs were randomly divided into 2 groups and models of CPB with pulmonary perfusion were established by perfusion of 4 C FA solution through proximal pulmonary artery in the experiment group while control group only received 4 C crystal cardiac arrest solution without pulmonary perfusion. Changes in the content of ET, NO, malonaldehyde （MDA）, dry to wet （D/W） in lung tissue and lung function- related indices PaO2/FiO2, airway pressure （AWP）, pulmonary vascular resistance （PVR）, lung compliance before and after CPB in both groups were measured respectively. Results ET content increased after CPB in control group （P〈0. 05） ,while experiment group had a lower level of ET than that of control group （P〈0.05）; D/W, MDA levels in experiment group decreased （P〈0. 05）, but NO content increased （P〈0. 05） as compared with control group. After pulmonary perfusion with FA, PaO2/FiO2 and lung compliance values in experiment group were higher than those of control group （P〈0.05）,AWP, PVR values lowered accordingly（P〈0. 05）. Lung injury was less severe in the experiment group. Conclusion ET is involved in pathogenesis of lung injury during CPB, FA can effectively reduce lung injury and improve lung function thus having a good protective effect on the lung.
ObjectiveTo observe the concentration of plasma endothelin (ET-1) in patients with nonarteritic anterior ischemic optic neuropathy(NAION) and investigate the relationship between ET-1 and NAION.MethodsThe plasma levels of ET-1 in 41 patients with NAION and 15 age-matched normal control subjects were measured by radioimmuoassay (RIA). The patients with NAION were divided into high papilloedema group, light papilloedema group, and recovery group according to the degree of papilloedema; and were divided into group1 (within 14 days), 2 (within 15-30 days), 3 (within 31-60 days), and 4 (within 61-180 days) according to the disease course. The plasma levels of ET-1 in different groups were detected and compared.ResultsThe plasma level of ET-1 in patients with NAION was significantly higher than that in the normal subjects (t=5.02，P＜0.05）and there was no obvious difference in NAION patients with different genders.There were significant differences of the plasma level among the groups with different degree of papilloedema（F=4.65，P＜0.05）. ET-1 plasma level gradually decreased as the disease course increased, and there were significant differences among the groups with different disease course（F=4.29，P＜0.05）. The difference of plasma level of ET-1 between Group 13 with corresponding disease courses and the control group was significant respectively(t1=5.92，t2=3.47，t3=2.18， P1lt;0.01, P2lt;0.05, P3lt;0.05)ConclusionThe plasma level of ET-1 in patients with NAION may be related to the degree of papilloedema lesion and disease courses. (Chin J Ocul Fundus Dis, 2005,21:156-158)
Objective To investigate the alteration of protein kinase C (PKC) and endothelin system in early diabetic rats, and the effect of specific PKC inhibitor on the expression of retinal endothelin-1 (ET-1). Methods The rats model with streptozotocin(STZ)-induced diabetes were set up. The expression of retinal PKC was detected by enzyme-linked immunoabsorbent assay (ELISA). The expression of retinal ET-1, ET-3, ET-A and ET-B receptor mRNA was determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The alteration of retinal ET-1 mRNA after intravitreal injection of PKC inhibitor GF109203X in diabetic rats was also observed. Results The activities of membranous PKC were significantly increased in 2-week diabetic rats compared with that in normal rats（t=3.296 , P=0.008）, while activities of cytosolic PKC were unchangeable（t=0.138, P=0.894）. The expression of retinal ET-1 mRNA was significantly increased（P=0.008）, while no change was found in expression of ET-3, ET-A and ET-B mRNA（P=0.918，P=0.889，P=0.500）. After intravitreal in jection of 10-5、10-6、10-7 mol/L PKC inhibitor GF109203X in diabetic rats, the expression of retinal ET-1 mRNA was decreased in a dose-dependent manner compared with the control rats. Conclusion Activation of PKC and increased expression of ET-1 could be found in the retina of early diabetic rats, and PKC inhibitor could inhibit the expression of retinal ET-1. (Chin J Ocul Fundus Dis，2004，20：168-171)
Objective To study the changes of endothelin (ET) and nitric oxide (NO) in the local site of vein transfer with delayed breaking pedicle and the relation with vasospasm and vein transfer in rabbits. MethodsThe ET concentration of blood was determined with the radioimmunoassay method. The plasma NO-2,NO-3 levels in the local site of vein transfer with delayed breaking pedicle, which reflected NO levels indirectly, were detected with Ultravioletvisible (UvVIS ) spectrophotometer. ResultsThe endothelin concentration of blood was increased significantly at 2, 4 hour after the operation (P＜0.01), and at 8 hour after the operation (P＜0.05). The plasma NO level was significantly decreased at 2, 4 hour after the operation (P＜0.01). But at 24 hour after the operation, the plasma NO level was increased significantly (P＜0.05). Conclusion The recovery of ET concentration of blood and the increase of plasma NO at 24 hour after the operation are the cause of the reduced incidence of vascular crisis of vein transfer with delayed breaking pedicle, and the very time point is the optimum moment for pedicle breaking.
ObjectiveTo investigate the change of renal endothelin (ET) excretion and its relation to renal dysfunctions in obstructive jaundice.MethodsSixty male Wistar rats were randomized into two groups, the common bile ducts were ligated to establish the model of obstructive jaundice in experimental group, and only sham operation was done in control group. Ten rats were taken from each group at 5, 10 and 15 days respectively after operation, renal functions were evaluated by paminohippuric acid clearance (CPAH), inulin clearance (CIN) and fractional sodium excretion (FENa+); furthermore, plasma endotoxin (EX) level was determined, and ET1 contents in renal arterial plasma, renal venous plasma and renal tissue were detected. ResultsOnly FENa+ was significantly increased at the 5th day in experimental group; since the 10th day, all the three renal functional parameters gradually decreased, and FENa+ was significantly lower than that in control group at 15th day (P＜0.01 vs control). ②The plasma EX sustained at significantly higher levels after operation in experimental group (P＜0.01 vs control). ③The renal arterial plasma ET1 was significantly decreased, while the contents in renal venous plasma and renal tissue were significantly increased after operation in experimental group (P＜0.01 vs control). ④There were positive correlation between plasma EX and renal ET1 content, negative correlation between renal ET1 content and CPAH/CIN, and positive correlation between renal ET1 content and FENa+ (P＜0.01).ConclusionThe increased excretion of renal ET stimulated by endotoxemia may play an important role in the renal dysfunctions in obstructive jaundice.
Objective To investigate the correlation between the plasma endothelin (ET) and gastric mucosal pathology.MethodsIn this experiment,seven dogs who experienced common bileduct ligation were in experiment group, the other three dogs who underwent shamoperation were control group. By using specific radio immunological method, the plasma ET levels were determined in dogs before and after 1,4,7 d. The total bilirubin levels were determined before and after 1,4,7 d after operation by using carbazotic acid method.The gastric mucosa,7 d after operation, was cut into slices and was examined under the electron microscope and the light microscope.Results In the experiment group,the levels of ET and total bilirubin rose continually and were higher than those in control group. Vascular congestion and oedema were seen in gastric mucosa of common bileduct ligated dogs. Under the electron microscope, we could see the dilated blood capillary and sludging of blood,the intenstitial mucusa cells oedema. Conclusion The increase of plasma ET might lead to impairment of mucosal microcirculation,which might be one of the pathogens that could induce the gastric mucosal damages in common bileduct ligated dogs.