Effects of High Dietary Protein on Coping Behavior, Memory Performance, and Sensory Discrimination in Rats.

Area of Science:

• Neuroscience
• Nutritional Science
• Behavioral Science

Background:

• High-protein (HP) diets, characterized by 50% casein, are associated with increased locomotor activity, heightened responses to pain, and elevated arousal levels compared to normal-protein (NP) diets (20% casein).
• Previous research indicates significant physiological alterations in rats consuming HP diets, prompting an investigation into potential cognitive consequences.

Purpose of the Study:

• To investigate the effects of a long-term high-protein diet on learning, memory, and sensory discrimination in Sprague-Dawley rats.
• To determine if HP diet consumption leads to deficits in cognitive functions and stress adaptation.

Main Methods:

• Male Sprague-Dawley rats were fed either an NP or HP diet ad libitum for 32 weeks.
• Behavioral assessments included the Porsolt swimming test for stress coping and the Morris Watermaze for spatial learning and memory.
• Auditory evoked responses were recorded to assess short-term auditory memory.

Main Results:

• Rats on the HP diet exhibited significantly reduced ability to develop coping strategies in the Porsolt swimming test (p < 0.05).
• Spatial learning and long-term memory recall in the Morris Watermaze were comparable between HP and NP diet groups.
• Short-term auditory memory traces degraded more rapidly in the HP group compared to the NP group (p < 0.05).

Conclusions:

• A long-term high-protein diet can induce deficits in short-term memory and impair the ability to cope with acute stress.
• These findings suggest that while long-term memory is preserved, specific cognitive functions are vulnerable to nutritional imbalances associated with high protein intake.