in order to identify the source of cortical afferents , injections of retrograde tracers such as wheat germ agglutinin conjugated with horseradish peroxidase ( wga-hrp ) , or the fluorescent substances fast blue or nuclear yellow , were placed in different parts of the parahippocampal cortex .
C0019941
horseradish peroxidase
C0078473
wga-hrp