'Homing' of Lucifer Yellow liposomes into hypothalamic neurons: a combined neuroanatomical Golgi and tracing technique.

Liposomes are combined with Lucifer Yellow in order to evoke neuronal uptake of this fluorescent dye in the medial basal hypothalamus. Lucifer Yellow liposomes are preferentially taken up by hypothalamic neurons. The dye spreads into the dendrites and axons, producing Golgi-revealing views of several neurons near the injection site in which both untrapped and liposome-entrapped Lucifer Yellow has been microiontophoretically administered. The capriciousness of the labeled neurons makes it possible to study the dendritic arborization and spines, while the axon with its collaterals can be followed to their targets. Moreover, the dye is also taken up retrogradely. When retrograde uptake over great distances occurs, the Golgi-like appearance is missing, because only then is perikaryal labeling found.