Rapidincrease inenzymeandpeptide mRNA insympathetic ganglia after electrical stimulation inhumans

ABSTRACT Thoracic ganglia in humans were studiedafterelectrical, preganglionic stimulation using in situ hybrid- ization with synthetic oligonucleotide probes againstthe cate-cholamine-synthesizing enzymes tyrosine hydroxylase (EC1.14.16.2) and dopamine f8-hydroxylase (EC 1.14.17.1) andneuropeptidetyrosine.Immunohistochemicalanalysiswasalsoperformed. Following short peroperative stimulation a sever-alfold increase in all three mRNAswas found in principalganglioncells, whereasnodefinitechangescouldbedetected in enzyme or peptide levels with immunohistochemistry. The results suggest a very rapid andsensitive regulation ofgenesinvolved in signal transmission in the sympathetic nervoussystem of humans. Moreover, they indicate that electricalstimulationofneuronsand/orpathwayscombined within situhybridization may be used as a method to derme neuronalprojections byvisualizing increases in mRNAsfortransmitterenzymes and/orpeptide in target cells. Several enzymes are involved in the synthesis ofcatechol-aminesin