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Release of neurolransmitters and other primary amine-containing analytes from intact, isolated larval salamander (Ambystoma tigrinum) retinas maintained in a 6.5-[micro]L perfusion chamber was monitored using online microdialysis-capillary eleclrophoresis with laser-induced fluorescence detection (CE-LIF). Primary amines were derivatized online with o-phthaldialdehyde (OPA) and [beta]-mercaptoethanol. With the use of overlapping injections, the perfusate was sampled every ~10 s. Although separation conditions were optimized using 20 mM hydroxypropyl-[gamma]-cyclodextrin (HP-[gamma]-CD) for a number of important neuromessengers including D- and L-serine, D- and L-asparate, glutamate, GABA, serotonin, dopamine, norepinephrine, and taurine, only glutamate (0.48 [+ or -] 0.27 [micro]M), GABA (0.25 [+ or -] 0.12 [micro]M), taurine (5.5 [+ or -] 2.1 [micro]M), and L-serine (2.8 [+ or -] 1.0 [micro]M) were identified in the perfusate. Elevated levels of glutamate, GABA, and taurine were detected during stimulation with 60 mM [K.sup.+]. This method is the first to directly sample multiple neurotransmitters from perfused, isolated retinas and to observe changes in efflux of these neurotransmitters as a result of pharmacological stimulation.