Co-localization of histamine and dopamine-beta-hydroxylase in sympathetic ganglion and release of histamine from cardiac sympathetic terminals of guinea-pig.
1. The aim of this study was to investigate the co-localization of histamine and dopamine-beta-hydroxylase in the superior cervical ganglion of guinea-pig and release of histamine from cardiac sympathetic terminals in guinea-pig isolated atrium. 2. Histidine decarboxylase (a histamine-synthesizing enzyme) mRNA signals were detected in the neurones of superior cervical ganglion of guinea-pig by in situ hybridization. The results of double-labelled immunofluorescence further confirmed the co-localization of histamine and dopamine-beta-hydroxylase in the large principle neurons and small intensely fluorescent cells in the superior cervical ganglion. The immunoreactivities of both histamine and dopamine-beta-hydroxylase were significantly attenuated after 6-hydroxydopamine-induced lesion of sympathetic nerves. 3. The refractory electrical field stimulation caused the release of histamine from cardiac sympathetic terminals of guinea-pig isolated atria (112.14 +/- 40.34 ng x ml(-1)), which was significantly attenuated to 35 +/- 15.57 ng x ml(-1) by reserpine pretreatment. Following administering compound 48/80, a mast cell degranulator, electrical field stimulation induced a dramatic increase of endogenous histamine release from isolated atria (303.57 +/-72.93 ng x ml(-1)). When compound 48/80 was added to the reserpine-treated atria, the release of histamine induced by field stimulation was decreased to 207.14 +/- 76.39 ng x ml(-1). 4 These results provide novel evidence that histamine co-exists with noradrenaline in sympathetic nerves and might act as a neurotransmitter to modulate sympathetic neurotransmission.
Li
M
M
Department of Pharmacology, The Fourth Military Medical University, Xi'an 710032, P R China.
Luo
X
X
Chen
L
L
Zhang
J
J
Hu
J
J
Lu
B
B
D000818:Animals; D004299:Dopamine beta-Hydroxylase / Q000737:chemistry* / Q000378:metabolism; D004558:Electric Stimulation / Q000379:methods; D005455:Fluorescent Antibody Technique / Q000379:methods; D015870:Gene Expression; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects / Q000378:metabolism; D006632:Histamine / Q000737:chemistry* / Q000378:metabolism; D006636:Histamine Release / Q000187:drug effects / Q000502:physiology*; D006640:Histidine Decarboxylase / Q000737:chemistry* / Q000378:metabolism; D017403:In Situ Hybridization; D007274:Injections, Intraperitoneal; D007275:Injections, Intravenous; D008297:Male; D016627:Oxidopamine / Q000008:administration & dosage / Q000009:adverse effects; D012333:RNA, Messenger; D012110:Reserpine / Q000008:administration & dosage / Q000493:pharmacokinetics; D017783:Superior Cervical Ganglion / Q000201:enzymology* / Q000378:metabolism / Q000648:ultrastructure; D017779:Sympathetic Fibers, Postganglionic / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
D012333:RNA, Messenger; D003189:p-Methoxy-N-methylphenethylamine; D006632:Histamine; D012110:Reserpine; D016627:Oxidopamine; D004299:Dopamine beta-Hydroxylase; D006640:Histidine Decarboxylase