pituitrin and Cystic-Fibrosis

Topics: Acute Disease; Adult; Cholestasis; Cystic Fibrosis; Esophageal and Gastric Varices; Gastrointestinal Hemorrhage; Humans; Hypertension, Portal; Infant; Sclerosing Solutions; Splenomegaly; Vasopressins

To understand potential mechanisms explaining interindividual variability observed in human sweat sodium concentration ([Na(+)]), we investigated the relationship among [Na(+)] of thermoregulatory sweat, plasma membrane expression of Na(+) and Cl(-) transport proteins in biopsied human eccrine sweat ducts, and basal levels of vasopressin (AVP) and aldosterone. Lower ductal luminal membrane expression of the Cl(-) channel cystic fibrosis transmembrane conductance regulator (CFTR) was observed in immunofluorescent staining of sweat glands from healthy young adults identified as exceptionally "salty sweaters" (SS) (n = 6, P < 0.05) and from patients with cystic fibrosis (CF) (n = 6, P < 0.005) compared with ducts from healthy young adults with "typical" sweat [Na(+)] (control, n = 6). Genetic testing of healthy subjects did not reveal any heterozygotes ("carriers") for any of the 39 most common disease-causing CFTR mutations in the United States. SS had higher baseline plasma [AVP] compared with control (P = 0.029). Immunostaining to investigate a potential relationship between higher plasma [AVP] (and sweat [Na(+)]) and ductal membrane aquaporin-5 revealed for all groups a relatively sparse and location-dependent ductal expression of the water channel with localization primarily to the secretory coil. Availability of CFTR for NaCl transport across the ductal membrane appears related to the significant physiological variability observed in sweat salt concentration in apparently healthy humans. At present, a heritable link between healthy salty sweaters and the most prevalent disease-causing CFTR mutations cannot be established.

Topics: Adult; Aldosterone; Aquaporin 5; Bicycling; Biopsy; Case-Control Studies; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; DNA Mutational Analysis; Epithelial Sodium Channels; Exercise; Fluorescent Antibody Technique; Genetic Predisposition to Disease; Hot Temperature; Humans; Kinetics; Mutation; Neurophysins; Phenotype; Protein Precursors; Sodium Chloride; Sweat; Sweat Glands; Sweating; Vasopressins; Young Adult

Sweat Na(+) concentration ([Na(+)]) varies greatly among individuals and is particularly high in cystic fibrosis (CF). The purpose of this study was to determine whether excess sweat [Na(+)] differentially impacts thirst drive and other physiological responses during progressive dehydration via exercise in the heat. Healthy subjects with high-sweat [Na(+)] (SS) (91.0 ± 17.3 mmol/l), Controls with average sweat [Na(+)] (43.7 ± 9.9 mmol/l), and physically active CF patients with very high sweat [Na(+)] (132.6 ± 6.4 mmol/l) cycled in the heat without drinking until 3% dehydration. Serum osmolality increased less (P < 0.05) in CF (6.1 ± 4.3 mosmol/kgH(2)O) and SS (8.4 ± 3.0 mosmol/kgH(2)O) compared with Control (14.8 ± 3.5 mosmol/kgH(2)O). Relative change in plasma volume was greater (P < 0.05) in CF (-19.3 ± 4.5%) and SS (-18.8 ± 3.1%) compared with Control (-14.3 ± 2.3%). Thirst during exercise and changes in plasma levels of vasopressin, angiotensin II, and aldosterone relative to percent dehydration were not different among groups. However, ad libitum fluid replacement was 40% less, and serum NaCl concentration was lower for CF compared with SS and Control during recovery. Despite large variability in sweat electrolyte loss, thirst appears to be appropriately maintained during exercise in the heat as a linear function of dehydration, with relative contributions from hyperosmotic and hypovolemic stimuli dependent upon the magnitude of salt lost in sweat. CF exhibit lower ad libitum fluid restoration following dehydration, which may reflect physiological cues directed at preservation of salt balance over volume restoration.

Topics: Adult; Aldosterone; Angiotensin II; Body Weight; Case-Control Studies; Cystic Fibrosis; Dehydration; Exercise; Female; Hot Temperature; Humans; Male; Osmolar Concentration; Plasma Volume; Sodium; Sweat; Thirst; Vasopressins

Topics: Cystic Fibrosis; Hemoptysis; Humans; Vasopressins

Desmopressin and vasopressin were used to control massive haemoptysis in a patient with cystic fibrosis. After bolus doses a continuous infusion of vasopressin was maintained for 36 hours and haemoptysis stopped.

Topics: Adult; Cystic Fibrosis; Deamino Arginine Vasopressin; Drug Therapy, Combination; Hemoptysis; Humans; Male; Vasopressins

The syndrome of inappropriate secretion of antidiuretic hormone was observed in two patients with cystic fibrosis during acute exacerbation of chronic pulmonary disease. It was diagnosed by the accepted clinical and laboratory criteria and confirmed in one case by values for immunoreactive vasopressin that were inappropriately high for plasma osmolality. The severe hyponatremia was corrected by fluid restriction, alone or combined with intravenous treatment with diuretic and hypertonic saline solution. In addition, there was simultaneous therapy of the pulmonary disease. SIADH thus must be added to salt loss as a cause of hyponatremia in CF, and may be more common than realized in patients with CF and severe pulmonary disease.

Topics: Adult; Cystic Fibrosis; Female; Humans; Hyponatremia; Male; Vasopressins

Topics: Blood Volume; Body Weight; Cystic Fibrosis; Humans; Hyponatremia; Vasopressins

Renal function studies were done in five children with infantile polycystic disease (IPCD)of kidneys and liver and in four with congenital hepatic fibrosis (CHF). Glomerular filtration rate was reduced in all IPCD patients and in two of four CHF patients. Urinary concentrating ability following water deprivation and vasopressin administration was impaired in all IPCD patients and in three of four CHF patients. During control period, all patients had asymptomatic metabolic acidosis with total carbon dioxide content less than or equal to 20.5 millimols/liter, and net acid excretion (NAE) was reduced in all but one. Ammonium chloride was administered to seven patients; NAE increased in all, but the increments were subnormal in four. The inability to excrete maximally concentrated urine and an adequate amount of net acid may best be explained by abnormal tubular structure or alterations in medullary architecture secondary to progressive scarring, or both.

Topics: Acidosis, Renal Tubular; Adolescent; Ammonium Chloride; Child; Child, Preschool; Cystic Fibrosis; Female; Glomerular Filtration Rate; Humans; Infant; Kidney Concentrating Ability; Kidney Diseases; Kidney Function Tests; Liver Cirrhosis; Male; Vasopressins; Water Deprivation

Topics: Adolescent; Adult; Child; Chlorides; Cystic Fibrosis; Diabetes Insipidus; Female; Humans; Iontophoresis; Male; Potassium; Sodium; Sweat; Sweat Glands; Sweating; Vasopressins

Topics: Adolescent; Child; Cystic Fibrosis; Diuresis; Female; Glomerular Filtration Rate; Humans; Kidney; Kidney Concentrating Ability; Kidney Function Tests; Male; Mannitol; Natriuresis; Sodium; Sodium Chloride; Vasopressins; Water; Water-Electrolyte Balance