Synaptic relationships between neurons containing vasopressin, gastrin-releasing peptide, vasoactive intestinal polypeptide, and glutamate decarboxylase immunoreactivity in the suprachiasmatic nucleus: dual ultrastructural immunocytochemistry with gold-substituted silver peroxidase.

摘要: In order to examine the morphological substrates for neuronal connections between cells of hypothalamic suprachiasmatic nucleus (SCN) that contain immunoreactivity different neurotransmitters, a double ultrastructural immunocytochemical analysis was used. For immunostaining, first neuroactive substance antigen labeled with goldsubstituted silver-intensified peroxidase (GSSP), which results in granular gold deposit high electron and light opacity. The second diaminobenzidine chromagen. The GSSP reaction product greatly increased visibility immunoreactive structures, both microscopy. Intensification method worked at all depths thick tissue sections as determined immunostained cut perpendicular their flat surface, 80-μm brain into horseradish (HRP) has been microinjected. On nitrocellulose dot-blot comparison HRP, intensification compared favorably tetramethylbenzidine, but unlike stable wide range buffers. addition diaminobenzidine, used intensify stabilize Hanker-Yates reagent tetramethylbenzidine on model system. Through use reaction, five new synaptic relationships were revealed. By increasing sensitivity by silver-gold intensification, immunoreaction could be found dendrites greater distance from perikaryon than nonintensified material. Because this sensitivity, contained cell origin dendrite sometimes identified. Boutons vasopressin-associated neurophysin make contact postsynaptic also vasopressin-neurophysin immunoreactivity. Similarly, boutons containing gastrin-releasing peptide made exhibiting