OBJECTIVETo evaluate the changes in the expressions of endothelial nitric oxide synthase (eNOS) and plasminogen activator inhibitor-1 (PAI-1) and the alterations of nitric oxide (NO) concentration in atrial endocardium in atrial fibrillation (AF) in order to investigate the mechanisms that contribute to thrombosis.

METHODSIn canine AF was produced with rapid atrial pacing at 400 bpm for 6 weeks, whereas the controls had no atrial pacing. NO production was measured by NO-specific microelectrode. The expression of endocardial eNOS and PAI-1 protein were determined by Western blot analysis and immunohistochemical Staining. Plasma levels of PAI-1 were analysed by Enzyme-linked immunoadsorbent assay.

RESULTSLeft atrial NO concentration was decreased in AF than that in controls [(23.4 +/- 5.8)nmol/L vs (63.8 +/- 16.1)nmol/L, P < 0.01]. Endocardial eNOS expression was also significantly decreased (855 +/- 217 vs 2320 +/- 694, P < 0.05), whereas the expression of the PAI-1 was increased (3164 +/- 827 vs 1371 +/- 352, P < 0.01). Neither NO concentration, nor PAI-1, eNOS expression were altered in the right atria at the same time. A significant increase for plasma levels of PAI-1 was also detected in AF group. No correlation was found between eNOS and PAI-1 protein expression (r = 0.217, P > 0.05).

CONCLUSIONIn the canine model AF was associated with a marked decrease in endocardial NOS expression and NO concentration and with an increase in PAI-1 expression in the left atrium, which may contribute to the thrombosis in AF.

Animals ; Atrial Fibrillation ; complications ; metabolism ; pathology ; Disease Models, Animal ; Dogs ; Female ; Male ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Plasminogen Activator Inhibitor 1 ; metabolism ; Thrombosis ; etiology ; metabolism ; pathology

Objective:To summarize our experience of retroperitoneal laparoscopic living donor nephrectomy,our continuous technical improvements and refinement of this skill and standardization of each procedure of this operation.Methods:Having approved by hospital ethical committee and local government administration,a total of 193 living donors underwent retroperitoneal laparoscopic living donor nephrectomy from Dec.2003 to Feb.2016 in our department.Under general anaesthesia,the operation was performed through 3 lumbar ports.After the kidney was liberated fully and the ureter was severed 7-8 cm under the lower pole of the kidney,the renal artery and vein were blocked with endo-cut or hem-o-lok separately and then severed.Then the kidney was taken out quickly and flushed with 4 ℃ kidney preserving fluid immediately,the donor kidneys were then preserved in iced saline until kidney transplantation.Clinical data about operation time,volume of blood loss,perioperative complications,renal function of both donors and recipients before and after operation were collected.Results:The 193 retroperitoneal laparoscopic living donor nephrectomy operations were successful with only one operation was converted to open living donor nephrectomy because of hemorrhage and unclear operation field during the operation.The average operation time was 85 min (55-135 min),the average blood loss was 60 mL (20-200 mL),and no donor needed blood transfusion during or after operation.Three donors were found to have hematoma of renal fossa after operation and none of them required further treatment.The average hospital stay after operation was 5.7 days (4-9 days).In the study,162 donors were followed up for an average of 42 months (1-58 months) and they were all healthy.Two kidney recipients had urinary bladder anastomosis leakage after operation and both needed surgical repair,a new anastomosis of ureter and bladder were made.Three kidney recipients had kidney subcapsular hematoma but required no further treatment.One kidney recipient had delayed graft function and recovered finally and the renal function of other recipients were all normal.Renal function of both donors and recipients during the follow up period were normal.Conclusion:Retroperitoneal laparoscopic living donor nephrectomy is a safe and reliable technique,it may become a standardized operation for living kidney transplantation after continuous technical improvement.Precautions must be taken to avoid complications and a skilled hand is necessary for success.