ABSTRACT
We cultured canine kidney (MDCK) cells stably expressing aquaporin-2 (AQP2) on collagen-coated permeable membrane filters and examined the effect of extracellular ATP on arginine vasopressin (AVP)-stimulated fluid transport and cAMP production. Exposure of cell monolayers to basolateral AVP resulted in stimulation of apical to basolateral net fluid transport driven by osmotic gradient which was formed by addition of 500 mM mannitol to basolateral bathing solution. Pre-exposure of the basolateral surface of cell monolayers to ATP (100 ?M) for 30 min significantly inhibited the AVP-stimulated net fluid transport. In these cells, AVP-stimulated cAMP production was suppressed as well. Profile of the effects of different nucleotides suggested that the P2Y2 receptor is involved in the action of ATP. ATP inhibited the effect of isoproterenol as well, but not that of forskolin to stimulate cAMP production. The inhibitory effect of ATP on AVP-stimulated fluid movement was attenuated by a protein kinase C inhibitor, calphostin C or pertussis toxin. These results suggest that prolonged activation of the P2 receptors inhibits AVP-stimulated fluid transport and cAMP responses in AQP2 transfected MDCK cells. Depressed responsiveness of the adenylyl cyclase by PKC-mediated modification of the pertussis-toxin sensitive Gi protein seems to be the underlyihng mechanism.
Subject(s)
Adenosine Triphosphate , Adenylyl Cyclases , Aquaporin 2 , Arginine Vasopressin , Baths , Cyclic AMP , Colforsin , Isoproterenol , Kidney , Madin Darby Canine Kidney Cells , Mannitol , Membranes , Naphthalenes , Nucleotides , Pertussis Toxin , Protein Kinase C , VasopressinsABSTRACT
A spontaneous rupture of the kidney due to a metastatic choriocarcinoma, which is associated with a normal pregnancy, is very rare. A 33-year-old female patient presented with sudden colicky right flank pain on the 5th day after a Cesarian Section. An abdominal CT scan showed evidence of a right renal rupture with a perirenal hematoma. Under the impression of a spontaneous rupture of right kidney, an exploratory laparotomy with a radical nephrectomy was performed. The pathologic findings revealed a renal parenchymal rupture due to a metastatic choriocarcinoma.
Subject(s)
Adult , Female , Humans , Pregnancy , Pregnancy , Choriocarcinoma , Flank Pain , Hematoma , Kidney , Laparotomy , Nephrectomy , Rupture , Rupture, Spontaneous , Tomography, X-Ray ComputedABSTRACT
PURPOSE: The purpose of this study was to find if any clinical or laboratory factors have significant correlations with blood loss caused by a transurethral resection of the prostate (TURP). MATERIALS AND METHODS: The medical records of 218 patients who had undergone a TURP were retrospectively reviewed. For each patient, the preoperative factors evaluated included age, type of presentation (patients who had been treated due to acute urinary retention; retention group, patients who had been treated due to lower urinary tract symptoms; symptomatic group), blood pressure, complete blood count, coagulation screening, prostate size on transrectal ultrasonography (TRUS), urine analysis, urine culture, ECG and drugs. Intraoperative and postoperative factors were also evaluated, including type of anesthesia, operator, operating time, weight of resected prostate tissue, blood transfusion and prostate histology. These factors were analyzed with respect to blood loss during the TURP using student's t, ANOVA and chi-square tests. RESULTS: The mean intraoperative blood loss and resected prostate weight were 415 ml and 15g, respectively. The factors which were found to significantly correlate with blood loss during a TURP were: resected prostate weight (r=0.44, p=0.0001), prostate size on TRUS (r=0.32, p=0.001), operating time (r=0.31, p=0.001), preoperative urine culture (p= 0.020), preoperative antimicrobials taken (p=0.020), and prostate histology (p=0.048). CONCLUSIONS: Of the factors found to correlate with blood loss during the TURP, the only reversible factor was a preoperative urinary tract infection. So, we expect that the prevention of preoperative urinary tract infection and its effective treatment in patients might be helpful in decreasing blood loss during a TURP.