Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The dive was carried out in the open sea to a depth of 850 fsw (26.7 ATA) for 6 days (DD 1--6) in the saturated mode, with personnel transfer capsule (PTC) excursions between 0 and 150 fsw and diver excursions between 0 and 50 fsw from the saturation base. Each diver had two excursion dives on alternate days. Although each PTC excursion lasted approximately 7 h, the actual time spent in the water averaged 10.5 min per diver. For 12 divers, daily excretion of water, electrolytes, aldosterone, and antidiuretic hormone (ADH) was studied, along with plasma composition (including prolactin), before, during, and after hyperbaric exposure. A significant increase in urine flow was observed on DD2--4 (1604 ml/day predive vs. 2300 ml/day on DD 4; P less than 0.05), after which the degree of diuresis decreased to about 1800 ml/day. Urine osmolality changed inversely with urine flow, with the lowest value of 532 mOsm/kg on DD 4. During the postdive period, both urine flow and urine osmolality returned to the predive level. The endogenous creatinine clearance was maintained at about 200 liters/day throughout the dive. The fractional excretion of Na+ remained unchanged while that of K+ increased significantly during hyperbaric exposure, thus decreasing the urinary Na+/K+ ratio. The fractional excretion of total osmotic substances showed a small hyperbaric exposure. Body weight decreased progressively during the initial 4 days of pressure exposure, equalling 2.6 kg on DD 4. These findings suggest that the observed diuresis may be accompanied by a net loss of body water. Neither the plasma prolactin level nor urinary excretion of aldosterone and ADHshowed any consistent change throughout the dive. It thus appears that, although there is a small osmotic component, the observed diuresis is primarily due to the ADH-independent inhibition of fre water reabsorption from the collecting duct by means of a mechanism yet to be identified.
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PMID:Urinary excretion of water and electrolytes during open-sea saturation diving to 850 fsw. 52 29

Cardiorespiratory, thermal, and renal responses to a 30-min head-out immersion in 15 degree C water were studied at 1-ATA air and 11-ATA helium-oxygne environments in four male subjects wearing dry suits. Cardiorespiratory responses to immersion (reductions in heart rate, expiratory reserve volume, vital capacity, and thoracic impedance; and increases in stroke volume, cardiac output, and inspiratory capacity) were comparable at both pressures. However, thermal responses to immersion (a reduction in mean skin temperature and increases in skin heat flux and suit conductance) were significantly greater at 11 ATA compared to those at 1 ATA. The rate of urinary excretion of norepinephrine increased significantly during and after immersion at 11 ATA but not at 1 ATA. In contrast, the urinary excretion of epinephrine was not altered by pressure or immersion. The immersion diuresis was greater and lasted longer at 11 ATA than at 1 ATA although there was no difference in the endogenous creatinine excretion . This diuresis was accompanied by a significant natriuresis which was more marked at 1 ATA than at 11 ATA. At 1 ATA, the urinary excretion of both aldosterone and antidiuretic hormone (ADH) decreased during immersion. At 11 ATA, the rate of excretion of these hormones before immersion was lower compared to that at 1 ATA and did not change significantly during immersion. These results indicate that immersion in a hyperbaric helium-oxygen environment presents a greater cold stress than at 1-ATA air, and also that immersion diuresis and natriuresis at high pressure may be induced by a factor other than inhibition of aldosterone and ADH.
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PMID:Physiological responses to head-out immersion in water at 11 ATA. 63 73

Comprehensive studies on body fluid balance on 5 divers were conducted during the Hana Kai II dive (17 days at 18.6 ATA and 7 days of decompression). Daily urine flow increased from about 2000 ml at 1 ATA to 2600 ml at 18.6 ATA, at 31 degrees C. This diuresis was accompanied by a reduction in urine osmolality (from 650 to 500 mOsm) and a slight increase in osmolal clearance. Endogenous creatinine clearance remained at about 173 ml/min throughout the dive. Despite such a sustained diuresis, neither daily water intake nor total body water volume changed significantly. The plasma renin activity changed little, while both plasma aldosterone concentration and urinary aldosterone excretion increased significantly during the first week at 18.6 ATA. The plasma prolactin concentration showed a significant decrease during the first 3 days at 18.6 ATA. The daily excretion of antidiuretic hormone (ADH) decreased significantly (by 40%) 4 days after compression and remained low throughout the rest of the dive. Insensible waterloss at 18.6 ATA was 35% lower than that at 1 ATA. It is suggested that the observed hyperbaric diuresis is due primarily to suppression of ADH as a result of suppression of insensible water loss.
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PMID:Hana kai ii: a 17-day dry saturation dive at 18.6 ATA. III. Body fluid balance. 91 Mar 16

When men are exposed to a hyperbaric environment, urine flow increases. In order to elucidate the mechanism of this hyperbaric diuresis, a dry saturation dive experiment was carried out. Five male subjects were exposed to a 16-21 ATA (atmospheric pressure absolute) helium-oxygen (He-O2) environment for 4 days. Five blood samples were obtained in the early morning (0600-0630 h): once at predive 1 ATA air, 3 times at 16-21 ATA He-O2, and once at postdive 1 ATA air. Eight-hour timed urine samples, 0600-1400 h, 1400-2200 h, and 2200-0600 h (night urine), were collected throughout the experimental period. Urine flow markedly increased by the exposure to hyperbaria in the presence of constant creatinine clearance. The increase was mostly attributable to the urine flow during 2200-0600 h. The secretion of antidiuretic hormone (ADH) was suppressed at daytime and night during the exposure. On the other hand, the secretion of atrial natriuretic polypeptide (ANP) increased solely at night during hyperbaria and correlated with the increases of both the nocturnal urine flow and the nocturnal urinary excretion of sodium. These results suggest that both suppressed ADH secretion and stimulated ANP secretion cause hyperbaric diuresis.
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PMID:Hyperbaric diuresis is associated with decreased antidiuretic hormone and increased atrial natriuretic polypeptide in humans. 183 Mar 48

Three male divers were studied for 2 days during each of the predive and postdive 1 ATA air control periods and for 7 days at 2.5 ATA (2.3 ATA N2 and 0.2 ATA O2). The chamber temperature was always maintained at a comfort level. Average urine flow remained at 1500 ml.day-1 during both predive and 2.5 ATA periods; urine osmolality also remained constant at around 700 mOSM/kg. On the other hand, daily excretion of Na increased significantly from 139 mEq during the predive period to 178 mEq at 2.5 ATA (P less than 0.05) but returned to the predive level during the postdive period. In contrast, daily K excretion decreased progressively with a significant decrease during the postdive period (P less than 0.05). Plasma osmolality, Na, and K remained unchanged, whereas a 6% reduction of total protein concentration at 2.5 ATA (P less than 0.05) was observed. A quantitatively similar decrease (8%) was observed for hematocrit during the 2.5 ATA period, which did not recover at postdive. These changes were accompanied by a significant increase in urinary excretion of antidiuretic hormone (P less than 0.05) and by decreases in both plasma renin and aldosterone (P less than 0.05) level and urinary excretion of aldosterone (P less than 0.05). Plasma atrial natriuretic factor remained unchanged throughout the entire dive period.
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PMID:Absence of diuresis during a 7-day saturation dive at 2.5 ATA N2-O2. 235 89

Four male divers were exposed to an environment of 1 ATA air for 7 d, followed by 7 d of 31 ATA He-O2, and following decompression to a postdive 1 ATA air environment for 3 d. Urine and blood were collected for hormonal measurements. Divided 24-h urine collections were obtained during 3 consecutive d at predive 1 ATA conditions, and at 31 ATA conditions. Two consecutive day collections were obtained at early decompression (31-25 ATA), at late decompression (14-8 ATA), and at postdive 1 ATA. Two blood samples were obtained, at predive 1 ATA, at 31 ATA, and at postdive 1 ATA. Plasma antidiuretic hormone (ADH) concentration decreased about 45% (P less than 0.005), while plasma aldosterone concentration and urinary aldosterone excretion were doubled (P less than 0.005) after the subjects were at 31 ATA. Plasma cortisol concentration and plasma parathyroid hormone concentration were not significantly affected by hyperbaria. Urinary excretion of aldosterone was not significantly different between day (0700-1900) and night (1900-0700) at any time, and both day and night excretion rates were increased at 31 ATA through late decompression (P less than 0.005). Urinary ADH excretion was greater during daytime at predive 1 ATA (P less than 0.005), but not thereafter. Both daytime and nighttime ADH excretion rates were decreased from 31 ATA through late decompression (P less than 0.005). It is concluded that hyperbaria eliminates the circadian release pattern of ADH and that the overall reduction of ADH may contribute to the increased free water clearance observed at hyperbaria. Also, increased parathyroid hormone was not associated with the phosphaturia observed at hyperbaria, but increased aldosterone coexisted with the increased kaliuresis observed.
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PMID:Seadragon VI: a 7-day dry saturation dive at 31 ATA. III. Alterations in basal and circadian endocrinology. 331 55

Three male subjects were passively tilted from a supine to a 90 degree head-up standing position on 2 d each at 1 and 31 ATA, then on 1 d of the postdive period. On each day the subjects were tilted once in the morning (0800-1000) and once in the evening (2000-2200). Before each tilt experiment, the subjects were first intravenously cannulated for blood sampling, then assumed the supine position. A blood sample was taken after 10 min in the supine position, and another sample was taken after 15 min of motionless, supported standing. The plasma was analyzed for antidiuretic hormone (ADH), plasma renin activity (PRA), plasma cortisol, and aldosterone. ADH, PRA, and cortisol were significantly increased by tilt, but the responses varied with time of day or atmospheric pressure. Cortisol increased only in the morning tilt (P less than 0.005) and was not affected by pressure. At 1 ATA, PRA was elevated in the morning tilt experiment (P less than 0.005) and not the evening tilt, but the overall response to tilt was greater at 31 ATA than at 1 ATA (P less than 0.005). The ADH response to tilt (P less than 0.025) was unaffected by time of day, but was eliminated at 31 ATA. The basal levels of ADH were also lower at 31 ATA (P less than 0.005). The mechanism of these responses remains unclear, but the eliminated postural stimulation of ADH may account for the eliminated circadian excretory pattern of the hormones. The altered responses to body fluid shifts possibly contribute to the increased aldosterone and decreased ADH frequently observed at hyperbaria.
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PMID:Seadragon VI: a 7-day dry saturation dive at 31 ATA. VI. Hyperbaria enhances renin but eliminates ADH responses to head-up tilt. 331 56

Four Japanese male subjects were studied during 3 days at 1 ATA, 3 days of compression to 31 ATA (1000 fsw), 14 days at 31 ATA, 12 days of decompression, and 3 days of postdive control at 1 ATA. The chamber was maintained at thermoneutral temperatures. During the 31-ATA exposure, urine flow increased about 500 ml/day (P less than 0.05) accompanied by an approximate 500-ml/day increase in osmotic clearance (Cosm) (P less than 0.05). Both urine flow and Cosm increases were primarily attributable to an increase in the overnight flow rates (P less than 0.01). The negative free water (-CH2O)/Cosm decreased during exposure to 31 ATA, indicating that a reduction in tubular water reabsorption may also contribute to the diuresis. Urine flow, Cosm, and -CH2O/Cosm all returned to predive values during decompression to 1 ATA. The urinary excretion rate of aldosterone increased from 2.7 +/- 0.3 micrograms/day at 1 ATA to 4.3 +/- 0.0 micrograms/day (P less than 0.01) at 31 ATA, remaining at about 3.8 micrograms/day until decompression. Urinary antidiuretic hormone (ADH) decreased from 50 +/- 7 to 33 +/- 3 mU/day (P less than 0.01) upon compression to 31 ATA and continued to decrease throughout the decompression phase. Plasma renin activity was increased by twofold (P less than 0.01) and plasma aldosterone by about 37% (NS) during exposure to 31 ATA. It is concluded that the reduction in ADH does not contribute significantly to the hyperbaric diuresis, and that the increased activity of the renin-angiotensin-aldosterone is a result of other postulated mechanisms resulting in an increased Cosm.
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PMID:Responses of salt- and water-regulating hormones during a saturation dive to 31 ATA (SEADRAGON IV). 637 32

To examine the weight loss of hyperbaric helium-oxygen habitation, we measured the exchange of liquids and calories in six men who lived in this atmosphere for 32 d. The maximum pressure was 49.5 ATA. The men lost 3.7-10.1 kg, in spite of warm ambient (31-32 degrees C) temperatures and adequate calories (2,737 kcal/d) provided for the sedentary ways of chamber living. Weight loss and a calculated fluid deficit were accompanied by significant hemoconcentration, shown by increases in serum proteins. These changes were followed by a rise in urinary aldosterone and vasopressin, but not thirst. Weight loss in hyperbaric atmospheres is probably multifactorial, but our data suggests an uncoupling of normal osmoregulation may have occurred in the present set of subjects. This may have been due to altered lung mechanics, increased catecholamines, or effects of high pressure on cellular responses to vasopressin.
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PMID:Is the weight loss of hyperbaric habitation a disorder of osmoregulation? 676 54

During mixed gas saturation diving (to 3-49.5 ATA) daily urine flow increases by about 500 ml/day, with no changes in fluid intake and glomerular filtration rate. The diuresis is accompanied by a significant decrease in urine osmolality and increase in excretion of such solutes as urea, K+, Na+, Ca2+ and inorganic phosphate (Pi). The fall in urine osmolality is mainly due to a reduction of free water reabsorption which is associated with a suppression of insensible water loss and the attendant inhibition of antidiuretic hormone (ADH) system. The increase in urea excretion may be associated with a reduction of urea reabsorption at the collecting duct as a consequence of ADH suppression. The rise in K+ excretion is due to a facilitated K+ secretion at the distal tubule as a result of increased aldosterone, urine flow and excretion of impermeable anions such as Pi. The activation of aldosterone system is partly attributed to a transient dehydration induced by early hyperbaric diuresis. The increase in Na+ excretion in the face of enhanced aldosterone secretion indicates that the Na+ transport in the proximal tubule is markedly inhibited (by unknown mechanism). The Pi excretion increases with no changes in plasma level of parathyroid hormone (PTH), thus it may be due to an inhibition of Na(+)-Pi cotransport in the proximal tubule. The increase in Ca2+ excretion may be secondary to the inhibition of Na+ transport at the proximal tubule. Precise information on the proximal tubular Na+ transport is important to understand the mechanisms of impaired solute transport under hyperbaric conditions.
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PMID:Renal function in hyperbaric environment. 957 38


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