Decrease of brain extracellular fluid [Na] and its interaction with other factors influencing sodium appetite in sheep.

R S Weisinger; D A Denton; M J McKinley; P G Osborne; E Tarjan

doi:10.1016/0006-8993(87)90248-4

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Decrease of brain extracellular fluid [Na] and its interaction with other factors influencing sodium appetite in sheep.

R S Weisinger·D A Denton·M J McKinley·P G Osborne·E Tarjan

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Abstract

It has been shown previously in sheep that physiological increase of cerebrospinal fluid (CSF) [Na] by infusion of 0.5 M NaCl artificial CSF causes a large reduction of sodium appetite of the sodium-deplete animal. Equivalent increase of CSF osmotic pressure caused by infusion 0.7 M mannitol artificial CSF which lowers CSF [Na] causes a doubling of sodium appetite. The results of the experiments here show that simple dilution of CSF [Na] with isotonic mannitol CSF, as distinct from use of hypertonic 0.7 M mannitol CSF, is an equally effective strong stimulus of sodium appetite. Lowering CSF [Na] concentration stimulates salt appetite in the severely sodium-deplete as well as in the mild to moderately sodium-deplete animal, and the effect of decrease of CSF [Na] on sodium appetite is sustained over 48 h. In addition, i.c.v. infusion of angiotensin II for the preceding 22 h at a rate which is an effective stimulus of both water and sodium solution intake in the sodium-replete animal, in fact, significantly decreased the sodium appetite stimulating effect of reduction of CSF [Na] in the Na-deplete animal.

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Angiotensin II Animals Brain Cerebrospinal Fluid Drinking Behavior Female Injections, Intraventricular Mannitol Plasma Saliva Sheep Sodium Journal Article Research Support, Non-U.S. Gov't

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R S Weisinger, D A Denton, M J McKinley, P G Osborne, E Tarjan. 1987-09-08. Decrease of brain extracellular fluid [Na] and its interaction with other factors influencing sodium appetite in sheep.. https://doi.org/10.1016/0006-8993(87)90248-4

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