A Saturated-Fat Diet during Development Alters Dendritic Growth in Mouse Brain

The objective of this study was to determine whether an essential fatty acid (EFA)-deficient diet (saturated fat) fed during development would alter the pattern of dendritic growth in pyramidal neurons of mouse occipital cortex. Pregnant and lactating mice were fed either a saturated fat or control diet throughout pregnancy and lactation. At weaning, one female was selected randomly from each litter, and these animals were maintained on their respective diets and reared in an enriched environment for eight weeks. Following this, their brains were processed histologically using a modified Golgi-Cox method, and patterns of dendritic growth were analysed in occipital pyramidal cells. A Sholl concentric circle analysis indicated that, for basilar dendrites, starting at a distance of 62.5 μm, animals fed saturated fat had fewer crossings than controls, which is indicative of either shorter dendrites or of less dendritic branching. Although the analysis of branching order was not significant, the trend seen in these data supports less branching in the saturated fat group, particularly of third- and fourth-order dendrites. Similar effects were seen in the apical dendrites, although to a lesser extent. Covariance analysis indicated that these effects could not be accounted for by the smaller brains in the EFA-deficient group. They can therefore be considered preliminary support for an effect of EFA on the pattern of dendritic development.