Figure 5.

Typical pattern of PRV infection in the medulla, pons and midbrain of cases sacrificed 5 days after inoculation of PRV-GFP into the TA muscle. The sections in panels A and B were from animals exhibiting the late day 4 pattern whereas those in panels C and D were from an animal with an early 5 day pattern of infection.

A. Coronal section (counterstained with cresyl violet) through the dorsal medulla showing infected neurons (black dots) in the ipsilateral rostral NTS (mNTS), parvocellular reticular formation (PCRT) and Probst’s nucleus (Prb) just lateral to the hypoglossal nucleus (NXII).

B. Counterstained coronal section through the pontine tegmentum showing infection of the ipsilateral locus ceruleus (LC). In this case, neither the mesencephalic trigeminal nucleus (meV) nor the dorsal tegmental nucleus (DTg) contained infected neurons though these structures were typically infected in 5 day patterns. Scale bar: 200μM

C and D. Counterstained 50μM thick coronal sections through the caudal (C) and rostral (D) periaqueductal gray (PAG). In C, infection of neurons in the dorsal (d), dorsolateral (dl) and dorsal part of the ventrolateral (vl) divisions is present bilaterally while infection of the ventral part of vlPAG is present ipsilaterally. Note the infection of a band of neurons extending from the laterodorsal tegmental nucleus (LDtg) to the pedunculopontine tegmentum (PPTg). In sections additionally stained with an antibody to choline acetyltransferase, none of the neurons in this band were double labeled. In D, infection is fairly restricted to the ipsilateral dorsolateral (dl) division of the PAG though a small cluster of cells (arrow), probably in the supraoculomotor central gray, is present just dorsal to the nucleus of Darkschewitsch (Dk) contralaterally. Scale bars: 200μM.