Fig. 5.

METH decreases tyrosine hydroxylase expression in vivo. Mice were subjected to an escalating METH dose schedule (s.c; twice daily) for 6 days, followed by a once daily administration of 10 mg/kg METH up to 56 days (a). Representative images of mouse coronal sections after 56 days are shown (b): Control (n = 3) and METH (n = 3) were stained for tyrosine hydroxylase. Five images at ×20 were taken for each mouse, and subsequent immunohistochemical analysis and quantification of tissue showed significant decreases (****p < 0.0001) in tyrosine hydroxylase expression in the striata of mice exposed to chronic METH treatment (c)