Fig. 3.

Inhibition of BDNF binding to cells increases BDNF detectability by standard ELISA. A, Immunostaining with an antibody against the extracellular domain of TrkB (Chemicon) in newborn NPG cultures grown for 3 d in the absence (Control) or presence of exogenous BDNF (+BDNF, 500 pg/ml). B, Mean levels of BDNF, detected with standard ELISA, in the absence (Control) or presence of anti-TrkB antibody (Anti-TrkB Ab, 10 μg/ml) in NPG cultures (hatched gray bars) and culture medium alone (hatched white bars) 48 hr after addition of 500 pg/ml BDNF. BDNF levels were also measured in control cultures (solid gray bars) to which exogenous BDNF was not added. ***p < 0.001;*p < 0.05;n.s., not significant.