pituitrin and Hydronephrosis

Topics: Glomerulonephritis; Humans; Hydronephrosis; Indicator Dilution Techniques; Kidney Concentrating Ability; Kidney Function Tests; Pyelonephritis; Vasopressins; Water Deprivation

Ageing of the kidneys has long been associated with a fall in the number of functioning nephrons resulting in a reduction of renal blood flow and glomerular filtration. This narrow concept of age-related changes in renal function has been developed chiefly during the last few years by Brenner et al. on the basis of experimental studies conducted on rodents. According to these authors, the size and frequency of segmental and focal lesions of glomerulosclerosis increase regularly with age, and in its final phase this pathology results in occlusion of glomerular capillaries. Renal ageing, therefore, can be assimilated to the nephron reduction models obtained by surgical ablation. The hypothesis that hypofiltration in certain nephrons is compensated by hyperfiltration in healthy glomerulis, leading to a vicious circle of self-destruction, was then applied to both ageing and experimental renal impairment: the smaller the number of nephrons, the greater the filtration achieved by the remaining nephrons, a process that accelerates the probability of their destruction. Conversely, any attempt to reduce intracapillary pressure or glomerular filtration slows down the progression of renal failure. This hypothesis is supported by experiments showing that reduction of protein intake or chronic inhibition of angiotensin I-converting enzyme activity are truly capable of limiting the progression of glomerulosclerosis induced in rats by partial renal mass ablation. Similarly, prolonged food restriction increases the life expectancy of rodents and almost totally prevents the occurrence of glomerulosclerosis. The experimental finding that degenerative renal lesions do not necessarily develop with age raises the problem of normal and pathological ageing. With an adequate choice of rats' food, strain and sanitary surroundings it is possible to obtain very old animals devoid of occluded glomerular capillaries and loss of nephron. What about the functional and structural changes due to ageing and not to pathology? This question has given rise to numerous studies which concluded, on the whole, that there exists a normal ageing of the kidneys without loss of nephron and that ageing is expressed by the fact that the kidneys have difficulties in adjusting themselves to disturbances in the inner environment. As regards renal functional reserve, response to the antidiuretic hormone in case of water restriction, or stimulation of the renin-angiotensin system in response to decrease of

Topics: Aging; Angiotensin-Converting Enzyme Inhibitors; Animals; Glomerular Filtration Rate; Glomerulosclerosis, Focal Segmental; Hydronephrosis; Hyperparathyroidism; Kidney; Kidney Concentrating Ability; Kidney Failure, Chronic; Nephrons; Rats; Vasopressins

Topics: Adolescent; Adult; Child; Child, Preschool; Diabetes Insipidus; Follow-Up Studies; Humans; Hydronephrosis; Hypothalamo-Hypophyseal System; Infant; Kidney Concentrating Ability; Pituitary Gland, Posterior; Vasopressins

Mammalian class IX myosin Myo9a is a single-headed, actin-dependent motor protein with Rho GTPase-activating protein activity that negatively regulates Rho GTPase signaling. Myo9a is abundantly expressed in ciliated epithelial cells of several organs. In mice, genetic deletion of Myo9a leads to the formation of hydrocephalus. Whether Myo9a also has essential functions in the epithelia of other organs of the body has not been explored. In the present study, we report that Myo9a-deficient mice develop bilateral renal disease, characterized by dilation of proximal tubules, calyceal dilation, and thinning of the parenchyma and fibrosis. These structural changes are accompanied by polyuria (with normal vasopressin levels) and low-molecular-weight proteinuria. Immunohistochemistry revealed that Myo9a is localized to the circumferential F-actin belt of proximal tubule cells. In kidneys lacking Myo9a, the multiligand binding receptor megalin and its ligand albumin accumulated at the luminal surface of Myo9a-deficient proximal tubular cells, suggesting that endocytosis is dysregulated. In addition, we found, surprisingly, that levels of murine diaphanous-related formin-1, a Rho effector, were decreased in Myo9a-deficient kidneys as well as in Myo9a knockdown LLC-PK1 cells. In summary, deletion of the Rho GTPase-activating protein Myo9a in mice causes proximal tubular dilation and fibrosis, and we speculate that downregulation of murine diaphanous-related formin-1 and impaired protein reabsorption contribute to the pathophysiology.

Topics: Albumins; Animals; Carrier Proteins; Cells, Cultured; Endocytosis; Formins; GTPase-Activating Proteins; Hydronephrosis; Kidney Tubules; LLC-PK1 Cells; Mice; Mice, Inbred C57BL; Mice, Knockout; Myosins; Nephrons; Polyuria; rho-Associated Kinases; Swine; Vasopressins

Polydypsia and polyuria are frequent symptoms in patients with sellar masses caused by neurohypophyseal diabetes insipidus. Autosomal dominant familial neurohypophyseal diabetes insipidus (adFNDI), a disorder caused by mutations in the arginine vasopressin (AVP) -neurophysin II (NPII) gene, should be considered as a rare differential diagnosis. A delayed diagnosis bears the risk of life-threatening electrolyte imbalances and permanent urinary tract damage, leading to impaired quality of life.We present a Caucasian kindred of at least 4 generations with FNDI.Clinical histories, endocrine para-meters, and results of molecular analyses of the AVP gene are presented with a review of the literature on diabetes insipidus (DI) related urinary tract dilatation.Polyuria and polydipsia were only reported based on explicit and thorough interrogation after more than 4 years of clinical follow-up. A novel heterozygous mutation in the AVP gene was found in all examined symptomatic subjects (c.1-33_c.4del37nt). A literature review revealed that non-obstructive hydronephrosis (NOH) is a rare but known complication of DI.Since increased fluid intake is often a typical familial pattern in adFNDI, it is frequently missed as being pathologic in affected patients, therefore a detailed clinical history of drinking volumes is of critical importance. AVP gene testing is an important component in the confirmation of the diagnosis. Otherwise unexplainable NOH should lead to further investigations and evaluation of rare diseases like FNDI.

Topics: Arginine Vasopressin; Child; Delayed Diagnosis; Diabetes Insipidus; Dilatation, Pathologic; DNA Mutational Analysis; Follow-Up Studies; Humans; Hydronephrosis; Kidney Function Tests; Kidney Pelvis; Magnetic Resonance Imaging; Male; Neurophysins; Pedigree; Protein Precursors; Sequence Analysis, DNA; Ureter; Urinary Bladder; Urinary Retention; Vasopressins

Topics: Child, Preschool; Diabetes Insipidus, Nephrogenic; Humans; Hydronephrosis; Male; Mutation; Neurophysins; Polyuria; Protein Precursors; Vasopressins

The release of prostaglandins E2, F2 alpha, I2 and thromboxane A2 from isolated perfused normal and hydronephrotic rabbit kidneys was investigated by extraction and radioimmunoassay. In both types of kidneys, basal PG efflux increased with time and was not altered by co-perfusion with dexamethasone or hydrocortisone. Several vasoactive substances at 1 to 4 micrograms (e.g., bradykinin, angiotensin II, substance P, noradrenaline and vasopressin) caused release of additional amounts of prostaglandins. PGE2 and 6-keto PGF1 alpha were the major prostanoids detected, but substantial amounts of PGF2 alpha were also found. Thromboxane A2 was not released from normal kidneys. In hydronephrotic kidneys there was greatly augmented release of prostaglandins E2 and I2, some increases in PGF2 alpha, and the appearance of substantial amounts of thromboxane A2 (measured as immunoreactive TXB2) when the kidneys were challenged with angiotensin, bradykinin and vasopressin, and smaller augmentation of the response to noradrenaline and substance P. There was no evidence that these evoked increases in renal PG output could be inhibited by dexamethasone or hydrocortisone. Some explanations for the failure of steroids to alter prostanoid metabolism from arachidonate in rabbit kidney are discussed, and it is proposed that there are clear exceptions to the concept that steroids inhibit prostaglandin generation in intact tissues.

Topics: Angiotensin II; Animals; Anti-Inflammatory Agents; Bradykinin; Depression, Chemical; Hydronephrosis; Kidney; Male; Norepinephrine; Prostaglandins; Rats; Thromboxane B2; Vasopressins

Topics: Animals; Diabetes Insipidus; Diuresis; Female; Glomerular Filtration Rate; Hydronephrosis; Kidney; Male; Osmolar Concentration; Rats; Rats, Brattleboro; Rats, Mutant Strains; Sex Factors; Vasopressins; Water-Electrolyte Imbalance

Topics: Adult; Diabetes Insipidus; Drug Resistance; Gout; Humans; Hydronephrosis; Kidney Diseases; Male; Vasopressins

Three cases of compulsive polydipsia previously diagnosed as diabetes insipidus are presented. Abnormally dilated bladder and pyelocalyceal systems were accompanying features, as previously described for diabetes insipidus, particularly of renal orign. Results of the hypertonic saline (Hickey-Hare) test were positive in only one case. Results of restriction of liquids followed by intravenous injection of vasopressin (Miller test) favoured a diagnosis of complete diabetes insipidus. These two tests cannot, therefore, exclude compulsive polydipsia. The features suggesting a diagnosis of compulsive water drinking are low plasma osmolality, a decrease in 24-hour urine output following water restriction, and abnormal behaviour. The diagnosis is confirmed by an 18-hour dehydration test done after gradual fluid restriction, which favours partial restoration of the papillary osmotic gradient.

Topics: Adolescent; Compulsive Behavior; Dehydration; Diabetes Insipidus; Diagnosis, Differential; Drinking; Female; Humans; Hydronephrosis; Hypertonic Solutions; Infusions, Parenteral; Middle Aged; Osmolar Concentration; Urinary Bladder Diseases; Vasopressins

A few rare syndromes have been delineated in which diabetes mellitus is inherited in association with other conditions. This paper describes five patients, including four siblings in one family, who have diabetes insipidus, diabetes mellitus, optic atrophy and deafness (the DIDMOAD syndrome). The parents of both families are normal but are first cousins. All the patients have insulin-dependent diabetes mellitus with a typical juvenile-onset. The onset of diabetes insipidus was insidious and the symptoms could easily have been ascribed to poor control of diabetes mellitus. The importance of diagnosing diabetes insipidus is that all these patients had dilatation of the urinary tract varying from mild hydroureter to severe hydronephrosis and this improved with treatment of the diabetes insipidus. It is suggested that patients with diabetes mellitus and optic atrophy should have regular screening tests for diabetes insipidus since it is likely that they represent cases of the full syndrome with incomplete clinical expression. The occurrence of this rare syndrome in four siblings of unaffected parents indicates that the syndrome is due to a recessive gene, but the pathogenesis is unknown.

Topics: Adolescent; Adult; Deafness; Diabetes Insipidus; Diabetes Mellitus; Female; Genes, Recessive; Humans; Hydronephrosis; Male; Optic Atrophy; Osmolar Concentration; Pedigree; Syndrome; Urinary Bladder; Urine; Vasopressins; Water Deprivation

Differential renal function studies performed on ten patients after release of unilateral hydronephrosis revealed that the previously obstructed kidney exhibits abnormalities in a number of physiological indexes. Many of the obstructed kidneys had an impairment of glomerular filtration rate, concentrating ability, acidification, sodium reabsorption and tubular maximal secretion of para-aminohippurate with normal urinary dilution. Despite impairment of sodium and water reabsorption, none of these patients, nor 20 additional patients, had a significant postobstructive diuresis from the previously obstructed kidney. All of the patients had normal total renal function. Thus, the changes observed were a result of the obstructive injury and were not related to azotemia or aberrations in water or sodium metabolism.

Topics: Adolescent; Adult; Aminohippuric Acids; Child; Chronic Disease; Desoxycorticosterone; Diuresis; Glomerular Filtration Rate; Humans; Hydronephrosis; Inulin; Kidney; Kidney Concentrating Ability; Mannitol; Ureteral Obstruction; Vasopressins

Topics: Blood Urea Nitrogen; Diabetes Insipidus; Diet Therapy; Humans; Hydronephrosis; Infant; Kidney Diseases; Male; Osmolar Concentration; Urethra; Urethral Diseases; Urethral Stricture; Urinary Tract Infections; Urography; Vasopressins; Water-Electrolyte Balance

Topics: Adult; Diabetes Insipidus; Humans; Hydronephrosis; Kidney Concentrating Ability; Male; Urinary Bladder; Urinary Bladder Neck Obstruction; Vasopressins

Topics: Adolescent; Diabetes Insipidus; Diuretics; Female; Humans; Hydrochlorothiazide; Hydronephrosis; Hypertrophy; Infant; Kidney Diseases; Male; Postoperative Complications; Sodium; Ureteral Obstruction; Ureterocele; Urinary Bladder Diseases; Urography; Vasopressins; Water

Topics: Adult; Humans; Hydronephrosis; Kidney Concentrating Ability; Kidney Function Tests; Kidney Tubules; Methods; Osmolar Concentration; Preoperative Care; Vasopressins

Topics: Adolescent; Child; Child, Preschool; Cystinosis; Diabetes Insipidus; Diuresis; Glomerulonephritis; Humans; Hydronephrosis; Infant; Infant, Newborn; Kidney Diseases; Kidney Diseases, Cystic; Polyuria; Pyelonephritis; Uremia; Vasopressins

Topics: Blood Chemical Analysis; Carbon Dioxide; Chlorides; Diabetes Insipidus; Diabetes Mellitus; Glucose Tolerance Test; Glycosuria; Hematuria; Humans; Hydronephrosis; Hyperglycemia; Nitrogen; Polyuria; Potassium; Pseudomonas Infections; Sodium; Urea; Urinary Tract Infections; Urine; Urography; Vasopressins

Topics: Child; Diabetes Insipidus; Diabetes Insipidus, Neurogenic; Dilatation; Enuresis; Humans; Hydronephrosis; Polyuria; Surgical Procedures, Operative; Urinary Bladder Neck Obstruction; Urography; Vasopressins

Topics: Diabetes Insipidus; Diabetes Insipidus, Neurogenic; Dwarfism; Humans; Hydronephrosis; Vasopressins

Topics: Bendroflumethiazide; Child; Diabetes Insipidus; Diabetes Insipidus, Nephrogenic; Diabetes Insipidus, Neurogenic; Diet, Sodium-Restricted; Electrolytes; Humans; Hydronephrosis; Infant; Intellectual Disability; Spironolactone; Vasopressins; Water-Electrolyte Balance