A study on rats raised on a high-fat diet found that they gained weight, experienced metabolic changes, and developed reduced insulin sensitivity and glucose tolerance. The rats also exhibited enhanced odor-aversion memory, which corresponded to increased neurotransmission in specific areas of the amygdala and hippocampus.
The study, published in the Journal of Neuroscience Research, aimed to explore how raising rats on a high-fat diet from weaning to adulthood would affect their metabolism, emotional memory, and neurotransmission. The researchers divided 66 male Wistar rats into two groups: one fed a normal diet, and another with large amounts of fat added to their diet.
The results showed that rats raised on the high-fat diet became overweight and exhibited multiple metabolic changes, including higher fasting blood glucose levels and decreased sensitivity to insulin. In the banana-scented water experiment, rats on the high-fat diet showed a stronger negative response to the banana scent after associating it with an aversive injection.
The study also revealed increased concentrations of neurotransmitters—glutamate, norepinephrine (noradrenaline), and dopamine—in rats on the high-fat diet during the period when they were learning to associate the aversive injection with the banana scent. The findings suggest that neuronal activity was heightened in the high-fat diet rats specifically during the aversion learning process.
The study’s authors concluded that their research highlights intricate connections between obesogenic diets, neurochemistry, and cognition, implying that metabolic dysfunctions due to consumption of hypercaloric diets can induce both detrimental and enhanced plasticity effects which may impact the overall brain health of individuals.
Source: https://www.psypost.org/high-fat-diet-alters-brain-function-and-memory-in-rats-new-study-shows/