Immunochemical staining of tyrosine hydroxylase(TH)-like material in the salivary glands and ventral nerve cord of the cockroach, Periplaneta americana (L.)

Abstract

This study examines the immunochemical staining of TH-like material in neurons of wholemount preparations of suboesophageal, thoracic and abdominal ganglia and salivary glands from immature and adult male cockroaches. A pair of neurons (SN1) in the suboesophageal ganglion, previously shown to contain catecholamines, stain intensely for TH-like material and are the only neurons identified which have a peripheral target (the salivary glands). The distribution of neurons containing TH-like immunoreactive material does not precisely overlap the distribution previously found for catecholamines using histofluorescence techniques. The axons of neurons which contain TH-like material in thoracic and abdominal ganglia appear to confine themselves to the central nervous system, thus suggesting that they probably function primarily to communicate and coordinate activity within the central nervous system. All neurons identified as containing TH-like material in the ventral nerve cord and the suboesophageal ganglion are bilaterally symmetrical. Of treatments used to enhance immunochemical staining of TH-like material, only prior injection of animals with pargyline appeared to marginally improve resolution of positive neurons.