Fig. 3. Neither GDNF nor NT3 increases the number of TH-immunoreactive noradrenergic neurons in E13.5 rat LCr primary cultures. Cells were treated with 30 ng/ml GDNF and/or 30 ng/ml NT3 and were analyzed after 6 days in vitro. Cell counts revealed no significant differences in the number of TH-positive cells between control wells and wells treated with GDNF, NT3 or GDNF+NT3.