Effect of acute manipulation of blood volume and osmolality on plasma [AVT] in seawater flounder

1995 ◽  
Vol 269 (5) ◽  
pp. R1107-R1112 ◽  
Author(s):  
J. M. Warne ◽  
R. J. Balment
Keyword(s):  
Linear Relationship ◽  
Blood Volume ◽  
Intraperitoneal Injection ◽  
Natural Variation ◽  
Plasma Osmolality ◽  
Arginine Vasotocin ◽  
Plasma Composition ◽  
Separate Study ◽  
Positive Linear Relationship ◽  
Plasma Arginine

Chronically cannulated seawater (SW)-adapted flounder (Platichthys flesus) were used unanesthetized and unrestrained in an experimental series that acutely manipulated blood volume and plasma osmolality to determine their influence on plasma arginine vasotocin (AVT) concentrations. Immunoreactive AVT was measured using a radioimmunoassay validated for flounder and other teleosts. After hemorrhage-induced hypovolemia or hypervolemia produced by saline infusion, no major changes in plasma AVT concentrations were detected. Raising plasma osmolality by intraperitoneal injection of 1 M NaCl compared with control 150 mM NaCl-injected fish (329.4 +/- 3.4 vs. 320.4 +/- 3.0 mosmol/kgH2O, P < 0.05) produced an increase in plasma AVT concentration (6.7 +/- 1.2 vs. 4.2 +/- 0.2 fmol/ml, P < 0.05). In a separate study, plasma composition in a large number of uncannulated SW-adapted flounder was determined. This demonstrated a positive linear relationship between the natural variation in plasma AVT concentrations and plasma osmolality and Na+ and Cl- concentrations observed between fish. These data indicate that AVT secretion in SW-adapted flounder is closely related and perhaps directly sensitive to changes in plasma tonicity.

Prompt recovery of plasma arginine vasopressin in diabetic coma after intravenous infusion of a small dose of insulin and a large amount of fluid

1990 ◽  
Vol 122 (4) ◽  
pp. 455-461 ◽  
Author(s):  
San-e Ishikawa ◽  
Toshikazu Saito ◽  
Koji Okada ◽  
Shoichiro Nagasaka ◽  
Takeshi Kuzuya
Keyword(s):  
Blood Volume ◽  
Serum Protein ◽  
Arginine Vasopressin ◽  
Small Dose ◽  
Plasma Osmolality ◽  
Diabetic Coma ◽  
Diabetic Patients ◽  
Volume Depletion ◽  
Circulating Blood Volume ◽  
Plasma Arginine

Abstract. We studied the changes in plasma arginine vasopressin in 5 patients with diabetic ketoacidosis and one patient with non-ketotic hyperosmolar coma who had marked hyperglycemia (36.6 ± 4.6 mmol/l, mean ± sem) and dehydration. Plasma osmolality (Posm) was 342.2 ± 11.4 mOsm/kg H2O, and hematocrit, serum protein, and blood urea nitrogen were also elevated at hospitalization. Circulating blood volume was decreased by approximately 21% as compared with that on day 7. Plasma AVP level was increased to 8.5 ± 1.6 pmol/l at hospitalization. When hyperglycemia was improved by iv infusion of a small dose of insulin plus fluid administration, plasma AVP level promptly decreased to 2.4 ± 0.4 pmol/l within six hours. When plasma AVP level had normalized, Posm was still as high as 305 mOsm/kg H2O, but the loss of circulating blood volume was only 4.2% of the control state. Plasma AVP level was positively correlated with change in hematocrit (plasma AVP = 3.58 + 0.45 · hematocrit, r = 0.468, p < 0.01), serum protein (r = 0.487, p < 0.01), Posm (r = 0.388, p < 0.01), and blood glucose (r = 0.582, p < 0.01). Plasma AVP level was negatively correlated with the change in circulating blood volume (plasma AVP = 3.6 – 0.14 · change in circulating blood volume, r = −0.469, p <0.01). These results indicate that both non-osmotic and osmotic stimuli are involved in the mechanism for AVP release in patients with diabetic coma, and that the non-osmotic control of AVP may contribute to circulating homeostasis, protecting against severe blood volume depletion in diabetic patients suffering from hyperglycemia and dehydration.

Osmotic and volemic regulation of plasma arginine vasotocin in conscious domestic fowl

1986 ◽  
Vol 250 (4) ◽  
pp. R644-R657
Author(s):  
J. N. Stallone ◽  
E. J. Braun
Keyword(s):  
Antidiuretic Hormone ◽  
Domestic Fowl ◽  
Hormone Secretion ◽  
Plasma Osmolality ◽  
Arginine Vasotocin ◽  
Antidiuretic Hormone Secretion ◽  
Primary Determinant ◽  
Plasma Arginine ◽  
Highly Correlated ◽  
Secretory System

Recently developed radioimmunoassay methods were utilized to quantitatively characterize secretion of the avian antidiuretic hormone [arginine vasotocin (AVT)] by the hypothalamo-neurohypophyseal system (HNS) of the conscious domestic fowl. The functional characteristics of the osmoreceptor-HNS were evaluated during independent experimental manipulations of extracellular osmolality or volume. Simultaneous measurements of plasma AVT (PAVT) and either plasma osmolality (Posm) or blood volume (BV) in these experiments permitted determination of osmoreceptor sensitivity to independent osmotic or volemic stimuli and set point of the AVT secretory system under conditions of normal hydration. In normally hydrated birds, PAVT and Posm averaged 2.7 +/- 0.2 microU/ml (12.9 +/- 1.0 pg/ml) and 308.1 +/- 0.6 mosmol/kg H2O, respectively (means +/- SE). Characterization of AVT secretion revealed that Posm is a primary determinant of AVT secretion by the HNS of the domestic fowl. Highly correlated and significant relationships between Posm and PAVT exist both above and below the observed basal Posm of normally hydrated birds, with an apparent osmotic threshold for AVT secretion at a Posm of 288.8 mosmol/kg H2O. Analysis of the data also suggested that the HNS is insensitive to changes in BV less than or equal to 10%, because neither isotonic expansion nor reduction of BV altered PAVT. Comparison of past and present avian data with that of the mammalian HNS indicates that 1) the osmotic regulation of antidiuretic hormone secretion is qualitatively and quantitatively similar in birds and mammals, and 2) the volemic regulation of antidiuretic hormone secretion is substantially more important in mammals than in birds.

Log linear relationship between plasma arginine vasopressin and plasma osmolality.

1977 ◽  
Vol 233 (1) ◽  
pp. E37
Author(s):  
R E Weitzman ◽  
D A Fisher
Keyword(s):  
Steady State ◽  
Linear Relationship ◽  
Exponential Function ◽  
Arginine Vasopressin ◽  
Bolus Injection ◽  
Regression Line ◽  
Plasma Osmolality ◽  
Threshold Phenomenon ◽  
Plasma Arginine ◽  
Log Linear

The integrated plasma arginine vasopressin concentration (IpAVP) was determined by pooling the results of single samples collected every 3 min for 0.5 h in dehydrated, randomly hydrated, and water-loaded sheep. A linear relationship was observed between the log of the integrated AVP concentration and plasma osmolality. This relationship was tested by the bolus injection of 20 g/100 ml NaCl to both water-loaded and randomly hydrated sheep. The rise in the log of IpAVP divided by the rise in plasma osmolality was similar in both groups (P greater than 0.5) and was superimposable upon the regression line derived from steady-state observations. The data would suggest that AVP is released as an exponential function of plasma osmolality rather than as a threshold phenomenon.

Regulation of plasma arginine vasotocin in conscious water-deprived domestic fowl

1986 ◽  
Vol 250 (4) ◽  
pp. R658-R664 ◽  
Author(s):  
J. N. Stallone ◽  
E. J. Braun
Keyword(s):  
Antidiuretic Hormone ◽  
Fluid Balance ◽  
Intravenous Infusion ◽  
Domestic Fowl ◽  
Water Deprivation ◽  
Extracellular Volume ◽  
Plasma Osmolality ◽  
Arginine Vasotocin ◽  
Plasma Arginine

Radioimmunoassay methods were employed to quantitatively characterize secretion of the avian antidiuretic hormone [arginine vasotocin (AVT)] by the hypothalamo-neurohypophyseal system (HNS) of the conscious domestic fowl in response to chronic dehydration. Water deprivation permitted characterization of AVT secretion in response to the combined stimuli of extracellular hyperosmolality and hypovolemia; the subsequent repletion of extracellular volume permitted separation of potential osmotic and volemic factors involved in the regulation of AVT secretion. In normally hydrated birds, plasma AVT (PAVT) and plasma osmolality (Posm) averaged 2.2 +/- 0.3 microU/ml (10.5 +/- 1.4 pg/ml) and 309.3 +/- 0.7 mosmol/kg H2O, respectively (means +/- SE). With water deprivation, PAVT and Posm of the birds increased in parallel in a curvilinear manner to maxima of 13.1 +/- 0.6 microU/ml (62.4 +/- 2.9 pg/ml) and 346.6 +/- 2.0 mosmol/kg H2O, respectively, at 96 h of dehydration. The isosmotic repletion of extracellular volume at 96 h by acute intravenous infusion failed to alter 96-h PAVT values. The results indicate that AVT secretion is closely linked to the state of hydration during negative fluid balance in the domestic fowl. Analysis of the data indicated that increases in PAVT that occur with dehydration are mediated primarily by extracellular hyperosmolality and that the HNS of the domestic fowl is relatively insensitive to the simultaneous hypovolemia incurred with fluid deprivation.

Brain-derived adrenomedullin controls blood volume through the regulation of arginine vasopressin production and release

2005 ◽  
Vol 288 (5) ◽  
pp. R1203-R1210 ◽  
Author(s):  
Meghan M. Taylor ◽  
Jennifer R. Baker ◽  
Willis K. Samson
Keyword(s):  
Blood Volume ◽  
Water Intake ◽  
Arginine Vasopressin ◽  
Plasma Osmolality ◽  
Plasma Potassium ◽  
Fluid Homeostasis ◽  
Protein Levels ◽  
Plasma Electrolyte ◽  
Physiological Regulator ◽  
Plasma Arginine

Central nervous system-derived adrenomedullin (AM) has been shown to be a physiological regulator of thirst. Administration of AM into the lateral ventricle of the brain attenuated water intake, whereas a decrease in endogenous AM, induced by an AM-specific ribozyme, led to exaggerated water intake. We hypothesized that central AM may control fluid homeostasis, in part by regulating plasma arginine vasopressin (AVP) levels. To test this hypothesis, AM or a ribozyme specific to AM was administered intracerebroventricularly, and alterations in plasma AVP concentrations were examined under basal and stimulated (hypovolemic) conditions. Additionally, we examined changes in blood volume, kidney function, and plasma electrolyte and protein levels, as well as changes in plasma aldosterone concentrations. Intracerebroventricular administration of AM increased plasma AVP levels, whereas AM ribozyme treatment led to decreased plasma AVP levels under stimulated conditions. During hypovolemic challenges, AM ribozyme treatment led to an increased loss of plasma volume compared with control animals. Although overall plasma osmolality did not differ between treatment groups during hypovolemia, aldosterone levels were significantly higher and, consequently, plasma potassium concentrations were lower in AM ribozyme-treated rats than in controls. These data suggest that brain-derived AM is a physiological regulator of vasopressin secretion and, thereby, fluid homeostasis.

scholarly journals Increases in Plasma ACTH and Cortisol after Hypertonic Saline Infusion in Patients with Central Diabetes Insipidus

2001 ◽  
Vol 86 (12) ◽  
pp. 5749-5754 ◽  
Author(s):  
Eiji Itagaki ◽  
Sachihiko Ozawa ◽  
Shinya Yamaguchi ◽  
Kenji Ushikawa ◽  
Teruaki Tashiro ◽  
...  
Keyword(s):  
Diabetes Insipidus ◽  
Hypertonic Saline ◽  
Plasma Osmolality ◽  
Central Diabetes Insipidus ◽  
Portal System ◽  
Plasma Acth ◽  
Acth Secretion ◽  
Acth Concentration ◽  
Plasma Arginine ◽  
Hypertonic Saline Infusion

To clarify the mechanism for the potentiation of CRH-induced ACTH response by the infusion of hypertonic saline, we investigated changes in plasma ACTH concentration after infusion of 5% hypertonic saline in five patients with untreated central diabetes insipidus (DI). Basal levels of plasma ACTH and cortisol in the DI group were not significantly different from those in normal control subjects. The infusion of hypertonic saline produced an increase in plasma arginine vasopressin (AVP) in controls, but did not elevate ACTH. However, in patients with DI, the plasma AVP concentration did not change, but circulating ACTH increased 3.6-fold (7.7 ± 1.5 to 23.0 ± 2.7 pmol/liter; P &lt; 0.01), and plasma cortisol also increased significantly (298 ± 99 to 538 ± 124 nmol/liter; P &lt; 0.05). Moreover, a positive correlation was observed between plasma ACTH and osmolality (r = 0.72; P &lt; 0.005). These results indicate that ACTH secretion in DI patients is regulated by a mechanism distinct from that in healthy subjects. It seems possible that the increase in plasma osmolality promotes ACTH secretion in DI patients through AVP and/or urocortin via the hypophyseal portal system, independent of the AVP secretion from magnocellular neurons.

Acid-base balance and plasma composition in the aestivating lungfish (Protopterus)

1977 ◽  
Vol 232 (1) ◽  
pp. R10-R17 ◽  
Author(s):  
R. G. DeLaney ◽  
S. Lahiri ◽  
R. Hamilton ◽  
P. Fishman
Keyword(s):  
Plasma Osmolality ◽  
Respiratory Acidosis ◽  
Electrolyte Balance ◽  
Plasma Composition ◽  
Total Plasma ◽  
Acid Base Balance ◽  
Acid Base ◽  
Plasma Bicarbonate ◽  
Arterial Ph ◽  
Base Balance

Upon entering into aestivation, Protopterus aethiopicus develops a respiratory acidosis. A slow compensatory increase in plasma bicarbonate suffices only to partially restore arterial pH toward normal. The cessation of water intake from the start of aestivation results in hemoconcentration and marked oliguria. The concentrations of most plasma constituents continue to increase progressively, and the electrolyte ratios change. The increase in urea concentration is disproportionately high for the degree of dehydration and constitutes an increasing fraction of total plasma osmolality. Acid-base and electrolyte balance do not reach a new equilibrium within 1 yr in the cocoon.

Acute and chronic increases in osmolality increase excitatory amino acid drive of the rostral ventrolateral medulla in rats

2004 ◽  
Vol 287 (6) ◽  
pp. R1359-R1368 ◽  
Author(s):  
Virginia L. Brooks ◽  
Korrina L. Freeman ◽  
Theresa L. O’Donaughy
Keyword(s):  
Amino Acid ◽  
Arterial Pressure ◽  
Blood Volume ◽  
Excitatory Amino Acid ◽  
Isotonic Saline ◽  
Plasma Osmolality ◽  
Saline Infusion ◽  
Ventrolateral Medulla ◽  
Depressor Response ◽  
Hypertonic Saline Infusion

Water deprivation is associated with increased excitatory amino acid (EAA) drive of the rostral ventrolateral medulla (RVLM), but the mechanism is unknown. This study tested the hypotheses that the increased EAA activity is mediated by decreased blood volume and/or increased osmolality. This was first tested in urethane-anesthetized rats by determining whether bilateral microinjection of kynurenate (KYN, 2.7 nmol) into the RVLM decreases arterial pressure less in water-deprived rats after normalization of blood volume by intravenous infusion of isotonic saline or after normalization of plasma osmolality by intravenous infusion of 5% dextrose in water (5DW). Water-deprived rats exhibited decreased plasma volume and elevated plasma osmolality, hematocrit, and plasma sodium, chloride, and protein levels (all P < 0.05). KYN microinjection decreased arterial pressure by 24 ± 2 mmHg ( P < 0.05; n = 17). The depressor response was not altered following isotonic saline infusion but, while still present ( P < 0.05), was reduced ( P < 0.05) to −13 ± 2 mmHg soon after 5DW infusion. These data suggest that the high osmolality, but not low blood volume, contributes to the KYN depressor response. To further investigate the action of increased osmolality on EAA input to RVLM, water-replete rats were also studied after hypertonic saline infusion. Whereas KYN microinjection did not decrease pressure immediately following the infusion, a depressor response gradually developed over the next 3 h. Lumbar sympathetic nerve activity also gradually increased to up to 167 ± 19% of control ( P < 0.05) 3 h after hypertonic saline infusion. In conclusion, acute and chronic increases in osmolality appear to increase EAA drive of the RVLM.

Altered osmotic thresholds for vasopressin secretion and thirst in human pregnancy

1984 ◽  
Vol 246 (1) ◽  
pp. F105-F109 ◽  
Author(s):  
J. M. Davison ◽  
E. A. Gilmore ◽  
J. Durr ◽  
G. L. Robertson ◽  
M. D. Lindheimer
Keyword(s):  
Plasma Osmolality ◽  
Late Pregnancy ◽  
Base Line ◽  
Urinary Volume ◽  
Human Pregnancy ◽  
Slow Infusion ◽  
Vasopressin Secretion ◽  
The Subject ◽  
The Mean ◽  
Plasma Arginine

Osmoregulation was studied in eight women during late pregnancy and again 8-10 wk postpartum. Base-line plasma osmolality (Posmol) was significantly lower during (280.9 +/- 2.1 mosmol/kg, SD) than after (289.4 +/- 2.1 mosmol/kg) pregnancy yet 24-h urinary volume and plasma arginine vasopressin (PAVP) measured in vasopressinase-inactivated blood was similar in both groups (pregnancy, 1.39 +/- 0.56 pg/ml; postpartum, 1.25 +/- 0.62 pg/ml). After 12 h of dehydration PAVP rose similarly and significantly both during (2.25 +/- 0.81 pg/ml) and after (2.89 +/- 1.19 pg/ml) gestation, and Uosmol was similar on both occasions (pregnancy, 779 +/- 121 mosmol/kg; postpartum, 784 +/- 102 mosmol/kg). When Posmol was increased by the slow infusion of 5% saline PAVP increased as soon as body tonicity did both during and after pregnancy. PAVP correlated significantly with Posmol in each subject (range of r, 0.75-0.99) and the mean regression lines [pregnancy, PAVP = 0.32 (Posmol; -279), r = 0.79; postpartum, PAVP = 0.38 (Posmol, -285), r = 0.86] demonstrated that the apparent osmotic threshold for AVP secretion was 6 mosmol/kg lower during than after gestation. Similarly the Posmol at which the subject experienced a conscious desire to drink was lower in pregnant (287 +/- 1.6 mosmol/kg) compared with postpartum subjects (298 +/- 2.0 mosmol/kg; P less than 0.001). These data demonstrate decreased osmotic thresholds for AVP release and thirst during human pregnancy and explain why gravidas can maintain their new lower Posmol within narrow limits.

scholarly journals Nutrient management on leaf area index of potato-mungbean- T. aman rice cropping pattern

2015 ◽  
Vol 39 (3) ◽  
pp. 515-527 ◽  
Author(s):  
MAH S Jahan ◽  
MAR Sarkar ◽  
M Salim
Keyword(s):  
Leaf Area Index ◽  
Linear Relationship ◽  
Leaf Area ◽  
Nutrient Management ◽  
Agricultural Research ◽  
Management Practice ◽  
Research Centre ◽  
Cropping Pattern ◽  
Area Index ◽  
Positive Linear Relationship

A field experiment was conducted at Regional Wheat Research Centre of the Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh for 2 consecutive years during 2006-07 and 2007-08. The objective was to find out the optimum nutrient management practice on leaf area index of each component crop of potato-mungbean-T. Aman rice cropping pattern. Twelve nutrient management treatments were tested in RCBD with 3 replications. Treatments combination based on cropping pattern were T1=HYG (0-198-44- 194-24-6-1.2 for potato; 0-24-40-48-24-3-1.2 for mungbean ; 0-80-16-44-12-2-0 for T.Aman rice ), T2=MYG (0-140-34-138-18-4.5-0.9 for potato; 0-20-36-40- 20-2-1 for mungbean ; 0-56-12-32-8-1.5-0 for T.Aman rice), T3=IPNS (10000- 168-38-170-18-6-1.2 for potato ; 5000-9-37-36-21-3-1.2 for mungbean ; 5000- 65-13-32-9-2-0 for T.Aman rice), T4=STB (0-171-40-164-22-5-1 for potato; 0- 20-36-40-22-2-1 for mungbean ; 0-68-15-37-11-2-0 for T.Aman rice), T5=FP (0- 97-16-91-0-0-0 for potato ; 0-6-5-4-0-0-0 for mungbean ; 0-39-37-12-0-0-0 for T.Aman rice), T6=CON (0-0-0-0-0-0-0 for potato, mungbean and T.Aman rice) kg/ha CDNPKSZnB, T7=HYG+CRI, T8=MYG+CRI, T9=IPNS+CRI, T10=STB+CRI, T11=FP+CRI, T12=CON+CRI for potato-mungbean T.Aman rice cropping pattern, respectively. Average of two years data showed that HYG+CRI treatment gave maximum LAI followed by HYG, IPNS+CRI, IPNS, STB+CRI, and STB treatments at 60 days after planting (DAP) for potato, at 50 days after sowing (DAS) for mungbean, at 60 days after transplanting (DAT) for T.Aman rice, respectively. For potato, there was a significant (p?0.01) and positive linear relation between the LAI at 60 DAP and the tuber yield. While there was a significant (p?0.01) and positive linear relationship between the LAI at 50 DAS and seed yield of mungbean. In case of T.Aman rice, there was a significant (p?0.05) as well as positive linear relationship between the LAI at 60 DAT and the grain yield of rice. DOI: http://dx.doi.org/10.3329/bjar.v39i3.21994 Bangladesh J. Agril. Res. 39(3): 515-527, September 2014

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