In preliminary studies we have shown that salt-hungry rats use information generated by sodium-specific elements in the liver to control their salt intake. The work proposed here will determine the contribution and context of this control relative to other mechanisms involved in the regulation of salt intake and sodium homeostasis. Our work and other research suggests the following tentative model: Ingested salt is slowly absorbed from the gastrointestinal tract and then carried by the hepatic-portal vein to the liver. the sodium is detected by sensors within the vein or liver, and the signal generated is relayed by afferent autonomic nerves to central integrative brainstem regions. These reduce subsequent salt intake, either directly, by modulating other brain regions, or indirectly, by ameliorating imbalances in the hormones of sodium homeostasis that cause salt hunger. We intend to test each stage of this model using salt-hungry rats to examine the following: (1) The relationship between salt intake and salt absorption, by measuring the appearance of sodium in the hepatic- portal vein after rats drink or administered various quantities of salt. (2) The effects on salt intake produced by pharmacological compromise of hepatic transduction. (3) The influence of disrupting transmission of information between the liver and brain by measuring salt intake of rats with selective liver denervations, and (4) the relationship between hepatic-portal levels of sodium and the hormones of sodium homeostasis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
1R01DK040099-01
Application #
3240193
Study Section
Biopsychology Study Section (BPO)
Project Start
1988-05-01
Project End
1991-04-30
Budget Start
1988-05-01
Budget End
1989-04-30
Support Year
1
Fiscal Year
1988
Total Cost
Indirect Cost
Name
Monell Chemical Senses Center
Department
Type
DUNS #
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Bachmanov, A A; Schlager, G; Tordoff, M G et al. (1998) Consumption of electrolytes and quinine by mouse strains with different blood pressures. Physiol Behav 64:323-30
Bachmanov, A A; Tordoff, M G; Beauchamp, G K (1998) Voluntary sodium chloride consumption by mice: differences among five inbred strains. Behav Genet 28:117-24
Tordoff, M G (1997) NaCl ingestion ameliorates plasma indexes of calcium deficiency. Am J Physiol 273:R423-32
Tordoff, M G (1997) Polyethylene glycol-induced calcium appetite. Am J Physiol 273:R587-96
Tordoff, M G (1996) Adrenalectomy decreases NaCl intake of rats fed low-calcium diets. Am J Physiol 270:R11-21
Coldwell, S E; Tordoff, M G (1996) Acceptance of minerals and other compounds by calcium-deprived rats: 24-h tests. Am J Physiol 271:R1-10
Okiyama, A; Torii, K; Tordoff, M G (1996) Increased NaCl preference of rats fed low-protein diet. Am J Physiol 270:R1189-96
Tordoff, M G (1996) The importance of calcium in the control of salt intake. Neurosci Biobehav Rev 20:89-99
Tordoff, M G (1996) Effect of chronic ouabain infusion on food, water, and NaCl intake, body composition, and plasma hormones of Sprague-Dawley rats. Physiol Behav 59:87-92
Tordoff, M G; Okiyama, A (1996) Daily rhythm of NaCl intake in rats fed low-Ca2+ diet: relation to plasma and urinary minerals and hormones. Am J Physiol 270:R505-17

Showing the most recent 10 out of 22 publications