TRANSNEURONAL LABELING OF NEURONS IN RABBIT BRAIN AFTER INJECTION OF HERPES-SIMPLEX VIRUS TYPE-1 INTO THE RENAL NERVE

We mapped the distribution of virus-labelled neurons in the brain after injection of Herpes simplex virus type 1 (HSV1) into the rabbit renal nerve. Seven days after injection, labelled neurons were observed in four brain regions, the rostral ventrolateral medulla (47 +/- 3% of neurons), the A5 area of the lower pons (38 +/- 4%), the caudal raphe nuclei and the parapyramidal area of the medulla (13 +/- 2%), and the paraventricular nucleus of the hypothalamus (1 +/- 1%). In the rostral ventrolateral medulla approximately one half of the HSV1-labelled neurons also contained tyrosine hydroxylase, characterizing them as C1 neurons. In the A5 area virtually all HSV1-labelled neurons also contained tyrosine hydroxylase. In the raphe nuclei and the parapyramidal area 47% of HSV1-positive neurons contained serotonin. The distribution of labelled neurons was similar to that observed after injection of HSV1 into the adrenal gland.