Morphological peculiarities of brain development in rats out of litters withdifferent numbers of animals in milk and pre-puberty stages of odontogenesis

Abstract

The authors studied the brain of 14- and 40-days old rats out of naturally scanty and large litters (SL and LL). An average number of rats in LL was 10,8 in a litter, in SL – 5,5; in 40-day old – 12 and 3,7 respectively In both age groups rats out of SL had larger (р<0,05), than in LL absolute mass of the brain, hemispheres and smaller relative mass of the brain, decreased number density of neurons in the cortex of the temporal lobe proper (PLP). The sizes of neurons in layer V of PLP in 14- and 40-day old rats out SL were larger than in LL. (р<0,05). In 40-day old rats out of SL the sizes of neurons in layer II of PLP and hyppocampus were smaller than in rats out of LL. (р<0,05). RNA concentration in cytoplasm did not have significant differences between the groups in the neurons of PLP < in the neurons of hyppocampus in rats out of SL it was higher than in rats out of LL. (р<0,05). NADN-d activity in the neurons of layer II of PLP in the brain of the rats out of SL was lower than than in LL., in layer V and hyppocampus neurons reliable differences between the groups were absent. NADFN-d activity in cytoplasm of neurons in neocortex and hyppocampus in 40-day old rats out of SL was lower of the same parameter in rats out of LL. (р<0,05).