The distribution of serotonin immunoreactivity (-IR) was studied in adult human carotid bodies, obtained at post-mortem, using both the peroxidase-antiperoxidase method on paraffin sections and a double-labelling immunofluorescence on frozen sections. Antibodies against synaptophysin and protein gene product (PGP) 9.5 were used for identification of serotonin-IR cells. Serotonin-IR was demonstr...

At synapses in the mammalian brain, continuous information transfer requires the long-term maintenance of homeostatic coupling between exo- and endocytosis of synaptic vesicles. Because classical endocytosis is orders of magnitude slower than the millisecond-range exocytosis of vesicles, high frequency vesicle fusion could potentially compromise structural stability of synapses. However, the mo...