Adenosine deaminase containing fiber pathway from the superior colliculus to the lateral posterior nucleus of the rat

Abstract

Presence of a projection containing adenosine deaminase (ADA)-like immunoreactivity from the stratum opticum (SO) to the dorsomedial portion of the lateral posterior nucleus of the thalamus (LPN) of the rat was demonstrated using a method combining retrograde tracing by horseradish peroxidase (HRP) and immunohistochemistry for ADA. In the caudal two thirds of the LPN, a clearly delimited ADA-like immunoreactive fiber plexus was located. Injection of HRP into the lateral posterior nucleus labeled many neurons in the medial portion of the SO where medium-sized neurons with ADA immunoreactivity were concentrated. Simultaneous immunostaining showed that some of the HRP-labeled neurons are ADA-positive.