Endogenous plasma atrial natriuretic peptide and the control of salt gland function in the Pekin duck

1997 ◽  
Vol 273 (3) ◽  
pp. R1080-R1085 ◽  
Author(s):  
D. A. Gray ◽  
C. Downing ◽  
N. Sayed
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Salt Gland ◽  
Gland Secretion ◽  
Pekin Duck ◽  
Salt Glands ◽  
Experimental Conditions ◽  
Salt Gland Secretion ◽  
Gland Function ◽  
Atrial Natriuretic

Polyclonal antibodies raised in a rabbit against avian atrial natriuretic peptide (ANP) were used to investigate the role of endogenous plasma ANP in the control of salt gland function of conscious, saltwater-adapted Pekin ducks. Salt gland secretion was initiated and maintained either by a hypervolemic (290 mosmol/kg NaCl i.v. at 2 ml/min) or hyperosmotic (1,000 mosmol/kg NaCl i.v. at 0.4 ml/min) stimulus. Both experimental conditions caused significant elevations in endogenous plasma ANP concentrations. At steady states of secretion driven by hypervolemia, the administration of ANP antiserum (anti-ANP), which reduced plasma ANP concentrations by 90%, caused an immediate 30% reduction in fluid secretion rate and sodium excretion that lasted for 20-30 min. The activity of salt glands driven by hyperosmolality was not changed by anti-ANP. The results show that the high circulating concentrations of endogenous ANP associated with conditions of sustained volume expansion promote salt gland secretion.

Role of endogenous atrial natriuretic peptide in volume expansion diuresis and natriuresis of the Pekin duck

1994 ◽  
Vol 140 (1) ◽  
pp. 85-90 ◽  
Author(s):  
D A Gray
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Volume Expansion ◽  
Polyclonal Antibodies ◽  
Physiological Role ◽  
Arginine Vasotocin ◽  
Pekin Duck ◽  
Plasma Parameters ◽  
Atrial Natriuretic

Abstract Polyclonal antibodies raised in a rabbit against avian atrial natriuretic peptide (ANP) were shown to reduce circulating endogenous ANP levels in Pekin ducks by more than 90%, and were subsequently used to investigate the role of this peptide in volume expansion diuresis and natriuresis. Conscious birds, undergoing a steady-state diuresis and natriuresis maintained by an i.v. infusion of hypotonic saline at a rate of 0·7 ml/min, responded to ANP antiserum (anti-ANP) with an immediate 30% reduction in urine flow rate and sodium excretion which lasted for about 30 min. Plasma arginine vasotocin levels were not changed by anti-ANP whereas circulating angiotensin II concentrations increased immediately following the administration of anti-ANP. Serum from non-immunized normal rabbits produced no changes in the renal and plasma parameters monitored. The results show that the high circulating levels of endogenous ANP associated with volume expansion promote renal salt and fluid excretion and thus have a major physiological role in avian volume homeostasis. Journal of Endocrinology (1994) 140, 85–90

Effects of hypoxia and atrial natriuretic peptide on aldosterone secretion in healthy subjects

1993 ◽  
Vol 75 (2) ◽  
pp. 534-539 ◽  
Author(s):  
R. G. Westendorp ◽  
A. N. Roos ◽  
M. Simons ◽  
W. Wertheim ◽  
F. H. Bosch ◽  
...  
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Arterial Oxygen Saturation ◽  
Free Water ◽  
Plasma Aldosterone ◽  
Arterial Oxygen ◽  
Aldosterone Secretion ◽  
Experimental Conditions ◽  
Placebo Condition ◽  
Atrial Natriuretic

To evaluate the inhibitory effect of hypoxia and atrial natriuretic peptide (ANP) on aldosterone secretion, 11 healthy male subjects were infused with 5 ng.kg-1 x min-1 ANP or placebo. The subjects were exposed in a stepwise fashion to incremental hypobaric hypoxia, which decreased arterial oxygen saturation to 79 +/- 2% in the placebo and 84 +/- 2% in the ANP condition (P < 0.05). In the placebo condition, the plasma ANP concentration increased from 13.8 +/- 1.0 to 19.6 +/- 2.3 pmol/l (P < 0.01) at the lowest barometric pressure. Plasma renin activity did not change, whereas the plasma aldosterone levels increased consequent to the increase of plasma adrenocorticotropic hormone (ACTH). Continuous infusion of ANP increased the plasma levels twofold (P < 0.001) and the level of guanosine 3',5'-cyclic monophosphate threefold (P < 0.001). However, the plasma aldosterone concentrations were not different in the two experimental conditions. Administration of supplementary oxygen significantly decreased ACTH to baseline values (P < 0.01) together with a decrease in aldosterone. Free water clearance (P = 0.05) but not sodium excretion (P = NS) increased during continuous ANP infusion. The data indicate that the aldosterone secretion in hypoxia is not inhibited by (patho)physiological plasma ANP levels. The inhibition of aldosterone secretion may well be explained by a direct effect of hypoxia on the adrenal cells. ACTH is a major stimulus of aldosterone secretion in hypoxia, which overrides the natriuretic effect of ANP.

Properties of body fluids influencing salt gland secretion in Pekin ducks

1980 ◽  
Vol 239 (5) ◽  
pp. R489-R496
Author(s):  
H. T. Hammel ◽  
C. Simon-Oppermann ◽  
E. Simon
Keyword(s):  
Extracellular Fluid ◽  
Salt Gland ◽  
Colloid Osmotic Pressure ◽  
Threshold Concentration ◽  
Gland Secretion ◽  
Salt Glands ◽  
Control Solution ◽  
Pekin Ducks ◽  
Salt Gland Secretion ◽  
Before And After

Pekin ducks were reared and maintained on 620 mosmol NaCl/kg H2O to enhance the secretory capability of their salt glands. When a control solution of 1,000 mosmol NaCl/kg H2O was infused intravenously at 0.2, 0.4, or 0.6 ml/min for 60-90 min, the infused loads were secreted in approximately equal quantities, indicating that the amount of NaCl in the extracellular fluid (ECF) before and after each infusion did not change. Salt and water secreted in response to experimental infusions of hyposmotic saline or blood were less than the solute and water infused. Thus, ECF volume increased and the Na+ concentration decreased. Infusions of control solution followed these experimental infusions. The salt and water secreted again equaled the amounts infused, indicating that the threshold concentration of Na+ ([Na+]th) for salt gland secretion was decreased by the increase in ECF volume. When the colloid dextran was added to the control solution, its infusion increased the colloid osmotic pressure of the blood and decreased nasal secretion. Because dextran increased the intravascular volume while the interstitial fluid volume (ISFV) decreased, we conclude that the [Na+]th was inversely correlated with ISFV.

Salt gland and kidney responses to intracerebral osmotic stimulation in salt- and water-loaded ducks

1984 ◽  
Vol 247 (6) ◽  
pp. R1022-R1028
Author(s):  
R. Gerstberger ◽  
E. Simon ◽  
D. A. Gray
Keyword(s):  
Cerebrospinal Fluid ◽  
Antidiuretic Hormone ◽  
Salt Gland ◽  
Gland Secretion ◽  
Salt Glands ◽  
The Third ◽  
Salt Gland Secretion ◽  
Artificial Cerebrospinal Fluid ◽  
Osmotic Stimulation ◽  
Urine Formation

Saltwater-adapted ducks with functioning supraorbital salt glands were chronically implanted with a device for perfusion of the third cerebral ventricle (icv perfusion) with artificial cerebrospinal fluid (CSF) of different tonicities. The osmoregulatory responses to icv stimulation were studied at conditions of salt and water loading in which only the salt glands, both salt glands and urinary fluid excretion, or only urinary fluid excretion were stimulated; in the latter experiments plasma antidiuretic hormone (ADH) was measured with a radioimmunoassay. Hypertonic icv stimulation enhanced salt gland secretion and caused antidiuresis, due to the increase of plasma ADH. Hypotonic icv stimulation inhibited salt gland activity and caused diuresis, due to the decrease of plasma ADH. Salt gland activity, urine formation, and plasma ADH reacted more sensitively to changes of icv tonicity in the hypertonic than in the hypotonic range. The effect of icv hypotonic stimulation could be obtained also with icv perfusion of isosmotic artificial CSF deficient in NaCl content. Perfusion with artificial CSF exceeding plasma tonicity by 50 mosmol X kg-1 or more caused inhibition of salt gland secretion associated with enhanced urinary output in several experiments.

Adrenergic and osmotic responses to atrial natriuretic peptide and angiotensin II in the duck (Anas platyrhynchos)

1987 ◽  
Vol 65 (9) ◽  
pp. 1995-1999 ◽  
Author(s):  
John X. Wilson
Keyword(s):  
Angiotensin Ii ◽  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Anas Platyrhynchos ◽  
Plasma Norepinephrine ◽  
Osmotic Regulation ◽  
Ang Ii ◽  
Salt Glands ◽  
Diuretic Response ◽  
Atrial Natriuretic

There is evidence that analogues of atrial natriuretic peptide (ANP) and angiotensin II (ANG II) occur in birds. The present experiments studied the adrenergic and osmoregulatory responses to synthetic ANP and ANG II in salt-loaded ducks (Anas platyrhynchos). Excretion of water and salt through the nasal salt glands was abolished by ANG II. This extrarenal, salt-retaining effect of ANG II was not altered by ANP. However, ANP did augment the diuretic response to ANG II. ANP also potentiated the stimulatory effect of ANG II on plasma norepinephrine. The data are consistent with physiological roles for native analogues of ANP and ANG II in adrenergic and osmotic regulation in the duck.

Sodium and potassium in spontaneously produced salt gland secretion and tears of ducks, Anas platyrhynchos, acclimated to fresh and saline waters

1969 ◽  
Vol 47 (6) ◽  
pp. 1133-1138 ◽  
Author(s):  
Maryanne Robinson Hughes ◽  
Frank E. Ruch Jr.
Keyword(s):  
Anas Platyrhynchos ◽  
Salt Gland ◽  
Gland Secretion ◽  
Domestic Duck ◽  
Salt Glands ◽  
Salt Gland Secretion ◽  
Harderian Glands ◽  
Nacl Concentration ◽  
Saline Waters ◽  
Sodium And Potassium

The spontaneously produced salt gland secretion (SGS) and tears of the domestic duck, Anas platyrhynchos, were analyzed for sodium (Na), potassium (K), and chloride (Cl) (Cl in SGS only). Acclimation to seawater did not enhance the concentrating ability of the salt glands. The NaCl concentration exceeded that of seawater by only a small margin. The tears of saline-acclimated birds contained less Na and more K than birds drinking water with low NaCl content. Salt stress significantly increased the weight of the salt glands and of the Harderian glands; the lacrymal glands were not affected. An estimation of the relative possible contribution of the cloacal fluid, SGS, and tears to cation excretion was made.

Responses of gull kidneys and salt glands to NaCl loading

1995 ◽  
Vol 73 (12) ◽  
pp. 1727-1732 ◽  
Author(s):  
Maryanne R. Hughes
Keyword(s):  
Glomerular Filtration Rate ◽  
Polyethylene Glycol ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Plasma Osmolality ◽  
Salt Gland ◽  
Urine Flow ◽  
Gland Secretion ◽  
Salt Glands ◽  
Salt Gland Secretion

Glomerular filtration rate was measured in Glaucous-winged Gulls, Larus glaucescens, acclimated to freshwater or saline and was also measured (along with salt gland secretion) following intravenous and intragastric infusion of 700 mM sodium chloride (NaCl). Freshwater- and saline-acclimated gulls had the same mean glomerular filtration rate, 5.6 ± 0.8 and 6.1 ± 1.0 mL ∙ min−1 ∙ kg−1; urine flow rate, 44 ± 20 and 46 ± 19 μL ∙ min−1 ∙ kg−1; urine/plasma osmolality ratio, 1.2 ± 0.2 and 1.7 ± 0.1; urine/plasma [14C]polyethylene glycol ratio, 210 ± 69 and 211 ± 64; and Na+ reabsorption, 99.6 ± 0.2 and 99.6 ± 0.3%, respectively. Renal function during 143 mM NaCl infusion (glomerular filtration rate, 3.4 ± 0.3 mL ∙ min−1 ∙ kg−1; urine flow rate, 19.7 ± 2.8 μL ∙ min−1 ∙ kg−1; urine/plasma osmolality ratio, 1.7 ± 0.1; urine/plasma [14C]polyethylene glycol ratio, 223 ± 26, and Na+ reabsorption 99.9 ± 0.0%) was not affected by subsequent infusion of 700 mM NaCl, although plasma osmolality was significantly increased. The urine/plasma ratio for [14C]polyethylene glycol, but not osmolality, was higher in gulls than in other avian species. Intravenously infused NaCl elicited less concentrated salt gland secretion at a significantly lower threshold plasma osmolality than intragastric NaCl infusion. Salt gland secretion and glomerular filtration rates were inversely related.Key words: bird, gull, Larus glaucescens, kidneys, salt glands, gut, sodium chloride, glomerular filtration rate, saline acclimation.

Sign in / Sign up

Export Citation Format

Share Document