Electron microscopic immunocytochemical evidence for the synaptic connections between tyrosine hydroxylase and substance P containing nerve elements in the coeliac ganglion of cat revealed by a double labelling technique.
In order to examine the morphological substrates for neuronal connections between neuronal elements of the coeliac-mesenteric ganglion containing immunoreactivity (IR) for tyrosine hydroxylase (TH) and substance P (SP), a double-immunostaining was performed. The first antigen to SP was labelled with gold-substituted silver-intensified peroxidase, which results in a granular gold deposit of high electron and light opacity. The second antigen was the TH labelled with peroxidase and a diaminobenzidine chromogen without silver-gold particles. About of 85% of the neurons contained TH immunoreactivity in the coeliac-mesenteric ganglia. The SP IR nerve fibres were mostly found around the principal ganglion cells throughout the ganglion. In most cases they made direct synaptic contact with TH positive nerve cells and dendrites. These SP-IR boutons were also found in synaptic contact with other non-labelled postsynaptic terminals and with the soma. SP-IR nerve terminals establish both symmetrical and asymmetrical synaptic contacts with TH-IR nerve elements. Some of the nerve cells which ware TH positive, were also labelled for SP. TH positive boutons were also observed in synaptic contact with other TH-IR perikarya and dendrites. Our results suggest that SP may play an important role for the integrative activities of the ganglion with regard to gastrointestinal functions.
Fehér
E
E
First Department of Anatomy, Semmelweis University Medical School, Budapest, Hungary.
Fodor
M
M
Donáth
T
T
D000818:Animals; D002415:Cats; D005260:Female; D005728:Ganglia, Sympathetic / Q000378:metabolism* / Q000648:ultrastructure*; D007150:Immunohistochemistry; D008297:Male; D016253:Microscopy, Immunoelectron; D013373:Substance P / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
D013373:Substance P; D014446:Tyrosine 3-Monooxygenase