title: Presence of vasoactive intestinal polypeptide-like immunoreactivity in the cholinergic electromotor system of Torpedo marmorata.
abstract: Vasoactive intestinal polypeptide (VIP)-like immunoreactivity was detected in the cholinergic electro-motor system of Torpedo marmorata using a combination of immunohistochemical assays, radioimmunoassay, and HPLC. The immunohistochemical assays revealed that the distribution of VIP-like immunoreactivity in the electric lobes, electromotor nerves, and electric organ is comparable to that of the stable cholinergic synaptic vesicle marker vesicle-specific proteoglycan. Ligation of the electromotor nerves caused a marked accumulation of VIP-like immunoreactivity in the lobes (180%) and the proximal portions of the electromotor nerves (130%) and a decrease in the electric organ (-50%), when measured by radioimmunoassay using synthetic VIP (porcine sequence) as the standard. VIP-like immunoreactivity in extracts of electric lobes electromotor nerves, and electric organ was eluted from a semipreparative reverse-phase HPLC column as a single peak with a retention time similar to that of porcine VIP. Rechromatography at higher resolution on an analytical column indicated diversity between the molecular forms of VIP-like immunoreactivity extracted from electric lobe and electric organ, suggesting the possibility of posttranslational processing.
mesh_terms: D000818:Animals; D002794:Choline / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D003714:Denervation; D004557:Electric Organ / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D006651:Histocytochemistry; D009420:Nervous System / Q000032:analysis*; D009424:Nervous System Physiological Phenomena; D011499:Protein Processing, Post-Translational; D011863:Radioimmunoassay; D014018:Tissue Distribution; D014101:Torpedo / Q000378:metabolism*; D014660:Vasoactive Intestinal Peptide / Q000032:analysis*
chemical_list: D014660:Vasoactive Intestinal Peptide; D002794:Choline