Fig. 4. Treadmill exercise prevents recognition memory impairment in VD
rats. #p<0.05 and##P<0.01 vs. C group;*p<0.05 and **P<0.01 vs. VD group.
Treadmill exercise rescued VD-induced synaptic ultrastructure deficits
Synaptic ultrastructure was the basis of structural synaptic plasticity.
Thus, we assessed hippocampal synapse numbers by transmission electron
microscope that are critical for the transmission of information related
to learning and memory. As shown in Fig. 3, hippocampal synapse numbers
were significantly decreased in the VD group compared to the control
group (P<0.05; Fig. 5B). These alterations were reversed by
treadmill exercise, and the rats exhibited healthier synaptic
ultrastructure, including significantly increased synapses and greater
synaptic connection density ((P<0.01; Fig. 5B)). Meanwhile, in
the Exe group, the number of synapses in the hippocampus were
significantly increased than those in C group (P<0.05;
Fig.5B). In conclusion, treadmill exercise ameliorated the above damage
and protect the ultrastructure of synapses, suggesting improved
structural synaptic plasticity.