Saline Preference Curve for Mice: Lack of Relationship to Pigmentation

Preference for 0.9% saline was examined, using two-bottle preference tests over 6-7 days, in the spontaneously hypertensive rat (SHR) and normotensive Wistar Kyoto rat (WK) of the Okamoto strain, the genetically hypertensive (GHR) and normotensive rat (NT) of the Smirk strain, and the Sprague-Dawley (SD), Dark Agouti (DA), and hooded Long-Evans or Brattleboro (BB) rat. Only the SHR exhibited a sustained and marked preference for 0.9% saline on each test day. The WK, GHR, NT, and SD preferred saline in the first 24-48 h of testing but thereafter showed neither a preference for, nor aversion to, saline. The BB showed neither a preference for, nor aversion to, saline in the first 24 h of testing and thereafter showed a significant aversion to saline on each test day. Saline preference was further examined in both the SHR and WK offered a choice of water and 0.9%, 2.0, or 2.7% saline. While preference for saline decreased in both SHR and WK with increasing saline concentration, the SHR maintained a significantly greater preference for saline and greater total sodium intake than the WK at each concentration. Hydralazine (5 mg . kg-1 . day-1, po) administered to SHR, while they were offered a choice of water and 0.9% saline, significantly lowered blood pressure over a 4-day period but failed to alter their saline preference significantly. We conclude that of the seven strains of rats examined only the SHR exhibited a preference for saline in extended two-bottle preference tests. Furthermore this preference for saline appears to be maintained independently of the blood pressure of the SHR.

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Effects of aging on mineralocorticoid-induced salt appetite in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00349.2013 ◽

2013 ◽

Vol 305 (12) ◽

pp. R1498-R1505 ◽

Cited By ~ 7

Author(s):

Robert L. Thunhorst ◽

Terry G. Beltz ◽

Alan Kim Johnson

Keyword(s):

Saline Solution ◽

Brown Norway ◽

Salt Appetite ◽

Aged Rats ◽

Middle Aged ◽

Renal Handling ◽

Saline Preference ◽

Old Rats ◽

Middle Aged Adult ◽

Effects Of Aging

This work examined the effects of age on salt appetite measured in the form of daily saline (i.e., 0.3 M NaCl) drinking in response to administration of deoxycorticosterone acetate (DOCA; 5 mg/kg body wt) using young (4 mo), “middle-aged” adult (12 mo), and old (30 mo) male Brown Norway rats. Water and sodium intakes, excretions, and balances were determined daily. The salt appetite response was age dependent with “middle-aged” rats ingesting the most saline solution followed in order by young and then old rats. While old rats drank the least saline solution, the amounts of saline ingested still were copious and comprise an unambiguous demonstration of salt appetite in old rats. Middle-aged rats had the highest saline preference ratios of the groups under baseline conditions and throughout testing consistent with an increased avidity for sodium taste. There were age differences in renal handling of water and sodium that were consistent with a renal contribution to the greater saline intakes by middle-aged rats. There was evidence of impaired renal function in old rats, but this did not account for the reduced saline intakes of the oldest rats.

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Effect of deoxycorticosterone on sodium appetite of intact and adrenalectomized rats

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.208.6.1281 ◽

1965 ◽

Vol 208 (6) ◽

pp. 1281-1285 ◽

Cited By ~ 69

Author(s):

George Wolf

Keyword(s):

Sodium Chloride ◽

Low Doses ◽

Sodium Appetite ◽

Self Selection ◽

Saline Preference ◽

High Doses ◽

Adrenalectomized Rats ◽

Stimulation Of ◽

Intact Rats

The effect of DOC on sodium chloride (saline) intake was studied in intact and adrenalectomized rats under "two-bottle" self-selection conditions. It was found that in adrenalectomized rats low doses of DOC produced a decrease in saline intake (restoration of sodium-retaining ability), whereas high doses produced an increase in saline intake (stimulation of sodium appetite). At high doses, however, intact rats consumed more saline and manifested a greater preference for it than did similarly treated adrenalectomized rats. Treatment with corticosterone increased both absolute saline intake and saline preference of DOC-treated adrenalectomized rats.

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Assessment of the transferability of biological habitat models for Atlantic salmon parr (Salmo salar)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-120 ◽

2003 ◽

Vol 60 (11) ◽

pp. 1398-1408 ◽

Cited By ~ 44

Author(s):

J C Guay ◽

D Boisclair ◽

M Leclerc ◽

M Lapointe

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Mathematical Structure ◽

Habitat Patches ◽

Suitability Index ◽

Preference Curve ◽

Substrate Size ◽

Salmon Parr ◽

Predicted Values ◽

Atlantic Salmon Parr

We assessed the transferability of the habitat suitability index (HSI) and the habitat probabilistic index (HPI) between two rivers. Transferability was measured by the ability of HSI and HPI models developed in the Sainte-Marguerite River to predict the distribution of Atlantic salmon parr (Salmo salar) in the Escoumins River. HSI and HPI were based on the pattern of utilization by fish of water depth, current velocity, and substrate size. HSI was developed using the preference curve approach, and HPI was developed using a multiple logistic regression. Predicted values of HSI and HPI in Escoumins River ranged from 0 (poor habitat) to 1 (excellent habitat). Fish density in habitat patches assigned different HSI or HPI values ranged from 0 to 1 fish·100 m–2. Only HPI adequately predicted local variations in parr density (r2 = 0.84) in habitat patches of Escoumins River. Our results suggest that HSI is less transferable between rivers than HPI. Differences in substrate size between the two rivers is suspected to impede the transferability of the HSI model. We also argue that the mathematical structure of HPI provides a larger degree of flexibility that facilitates its transferability and its potential generalization.

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