GABA Influences the Development of the Ventromedial Nucleus of the Hypothalamus
Journal of Neurobiology
cell migration, baclofen, VMH, GABA, brain development, ventromedial nucleus, hypothalamus
The region that becomes the ventromedial nucleus of the hypothalamus (VMH) is surrounded by cells and fibers containing immunoreactive gamma-aminobutyric acid (GABA) by embryonic day 13 (E13), several days before the nucleus emerges in Nissl stains. As GABA plays many roles during neural development, we hypothesized that it influences VMH development, perhaps by providing boundary information for migrating neurons. To test this hypothesis we examined the VMH in embryonic mice in which the β3 subunit of the GABAA-receptor, a receptor subunit that is normally highly expressed in this nucleus, was disrupted by gene targeting. In β3 −/− embryos the VMH was significantly larger, and the distribution of cells containing immunoreactive estrogen receptor-α was expanded compared to controls. Using in vitro brain slices from wild-type C57BL/6J mice killed at E15 we found that treatment with the GABAAantagonist bicuculline increased the number of cells migrating per video field analyzed in the VMH. In addition, treatment with either bicuculline or the GABAA agonist muscimol altered the orientation of cell migration in particular regions of this nucleus. These data suggest that GABA is important for the organization of cells during VMH formation.
Dellovade, Tammy L.; Davis, Aline M.; Ferguson, Caroyn; Sieghart, Werner; Homanic, Gregg E.; and Tobet, Stuart A.. "GABA Influences the Development of the Ventromedial Nucleus of the Hypothalamus." Journal of Neurobiology 49, no. 4 (2001): 264-276. Accessed at http://digitalcommons.framingham.edu/bio_facpub/18