Proximal tubule dopamine histofluorescence in renal slices incubated with L-dopa.
Renal cortex slices were incubated with amine precursors L-dopa, or L-5-HTP. Localization of synthesized amines, dopamine or serotonin, was examined by means of histofluorescence methods. Formaldehyde-induced fluorescence was present in the proximal convoluted tubule and not in the pars recta or other segments of the tubules after incubation in the presence of 10(-3) to 10(-7) M L-dopa. Tubule-induced fluorescence was not seen in the presence of an inhibitor of dopa-decarboxylase or in the absence of sodium. It was independent of innervation. It is concluded that dopamine and serotonin are accumulated and likely formed within proximal convoluted tubular cells.
D006916:5-Hydroxytryptophan / Q000378:metabolism; D000818:Animals; D001345:Autoradiography; D004298:Dopamine / Q000096:biosynthesis*; D005455:Fluorescent Antibody Technique; D005557:Formaldehyde; D006801:Humans; D066298:In Vitro Techniques; D007687:Kidney Tubules, Proximal / Q000378:metabolism* / Q000648:ultrastructure; D007980:Levodopa / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
D005557:Formaldehyde; D007980:Levodopa; D006916:5-Hydroxytryptophan; D004298:Dopamine