Increased plasma D-lactic acid associated with impaired memory in rats
Physiology & Behavior, 101, 653–659.
Hanstock, T.L., Mallet, P.E. & Clayton, E.H.
published: 2010 | Research publication | Journal article
Abstract: Aim: D-lactic acidosis is associated with memory impairment in humans. Recent research indicates that D-lactic acid may inhibit the supply of energy from astrocytes to neurons involved with memory formation. However, little is known about the effects of increased hind-gut fermentation due to changes in diet on circulating lactic acid concentrations and memory. Method: Thirty-six male Wistar rats were fed three dietary treatments; a commercial rat and mouse chow, a soluble carbohydrate based diet or a fermentable carbohydrate based diet. Parameters estimating memory were examined by employing the object recognition test. Physical parameters of fermentation including hind-gut and plasma lactic acid concentrations were examined after sacrifice, either 3 or 21 h after feeding. Results: Increased fermentation in the hind-gut of rats, indicated by lower caecum pH, was associated with increased plasma L-lactic acid (r = -0.41, p = 0.020) and D-lactic acid (r = -0.33, p = 0.087). Memory, being able to discriminate between a familiar and a novel object during the object recognition test, was reduced with increasing plasma D-lactic acid (r = -0.51, p = 0.021). Conclusions: Memory impairment was associated with alterations in plasma D-lactic acid following the fermentation of carbohydrate in the hind-gut. Further work is still required to determine whether these effects are mediated centrally or via direct connections through the enteric nervous system.
Download: PDF (231k) Hanstock_et_al_2010.pdf
revised Sep 11/10
View all Paul Mallet documents