Strain differences in consumption of saline solutions by mice

Area of Science:

• Neuroscience
• Behavioral Science
• Genetics

Background:

• Salt appetite is crucial for physiological homeostasis.
• Inbred mouse strains exhibit distinct behavioral responses to physiological challenges.

Purpose of the Study:

• To investigate strain-specific differences in saline (NaCl) preference between C57BL/6J (C57) and 129/J mice.
• To explore the role of prior saline exposure and postingestional consequences in salt preference.

Main Methods:

• Utilized 48-hour two-bottle preference tests comparing water and various saline concentrations.
• Administered lasix (diuretic) to induce sodium depletion and lithium chloride (LiCl) for toxicosis.
• Manipulated prior exposure to saline solutions.

Main Results:

• C57 mice rejected moderate saline (0.075-0.150 M), while 129/J mice preferred it.
• Both strains increased saline intake after sodium depletion.
• LiCl toxicosis abolished 129/J mice's preference for 0.15 M NaCl.
• C57 mice's saline rejection was partly due to prior saline exposure, unlike 129/J mice.

Conclusions:

• Significant strain differences exist in mouse salt preference.
• Postingestional consequences of saline consumption contribute to strain-specific salt preferences in C57 mice.
• 129/J mice's salt preference is less influenced by prior exposure or postingestional feedback.