A simple method for measuring dopamine release from rat brain slices.

In many circumstances, rapid information is required about the effects of drugs on neurotransmitter release in brain, and a common method used is measurement of radiolabelled release from superfused brain slices or synaptosomes in vitro. However, the method requires expensive equipment and is not readily adapted to the measurement of endogenous release. The method described here uses readily available cheap chromatographic columns to measure both radiolabelled and endogenous dopamine (DA) release from striatal slices in repeated incubation samples. The results showed that the [3H]DA release is sensitive to temperature, K(+)-stimulation, and to both a DA agonist (pergolide) and an antagonist (eticlopride). Endogenous DA release was also stimulated by high K+ (20 mM) and sensitive to a DA agonist. Pergolide (100 microM) reduced both [3H]DA and endogenous DA release, while eticlopride (10 microM) increased [3H]DA, but not endogenous DA release. The results demonstrate an alternative cheap and quick way to study neurotransmitter release from brain in vitro.