Fig. 3. Neural precursor cells grown in culture express the α-aminobutyric acid type A (GABAA) receptor. Western blot analysis reveals that 55 kD GABAAreceptor α-1 subunit is expressed in whole brain but not in independently isolated cultured neural stem cell lines (A ). The GABAAreceptor β-3 subunit was found in all stem cell lines that were analyzed as well as in whole brain (B ). Glyceraldehyde phosphate dehydrogenase (GAPDH) was used as a control. GABAAR= γ-aminobutyric acid type A receptor.