Appearance of the noradrenergic markers tyrosine hydroxylase and neuropeptide Y in cholinergic nerves of the iris following sympathectomy.

摘要: Selective autonomic denervations of the iris have been used to study possible redistribution adrenergic markers within adult nerve fiber systems and reveal cellular origin a nonsympathetic plexus induced express such markers. The presence distribution fibers showing neuropeptide Y (NPY)- tyrosine hydroxylase (TH)-like immunoreactivity was studied in rat using stretch-prepared whole mounts. Normal irides contained dense regular network NPY-positive varicose fibers. Such were regularly seen innervating blood vessels. choroid membrane had high number fluorescent A similar, although slightly denser TH-positive system visualized iris. One or 2 days after surgical removal superior cervical ganglion, almost all NPY- disappeared, suggesting that most, if not all, originate ganglion. In from long-term sympathectomized animals, TH- NPY-immunoreactive reappeared, while devoid catecholamine-containing fibers, as evidenced by Falck-Hillarp histochemistry. appearance sympathetically denervated clearly time dependent. intact animals showed obvious dissimilarities lower fluorescence intensity fewer irides. Furthermore, rats, associated with Unilateral parasympathetic ciliary which supplies cholinergic 3 prior sacrifice bilaterally 1 month earlier, led drastic reduction numbers on ciliarectomized/sympathectomized side compared sympathectomized-alone side. present experiments thus suggest neurons vivo are capable expressing characteristics under experimental conditions.