to identify the sources of the cholinergic input to the superior colliculus , injections of wheat germ agglutinin conjugated to horseradish peroxidase ( wga-hrp ) were made in the superior colliculus and the sections were processed to demonstrate both the retrograde transport of wga-hrp and chat immunoreactivity .
C0019941
horseradish peroxidase
C0078473
wga-hrp