Table 2.

Effects of systemic nicotine treatment on KYNA levels in different areas of the rat brain

	KYNA (fmol/mg protein)
	Striatum	Hippocampus	Frontal cortex
5 d
Control	137  ± 9	180  ± 19	209  ± 14
Nicotine	103  ± 4*	118  ± 7*	141  ± 9*
Δ (%)	75	66	67
15 d
Control	154  ± 8	181  ± 7	199  ± 4
Nicotine	191  ± 10*	213  ± 7*	227  ± 10*
Δ (%)	124	118	114

Nicotine (1 mg/kg, s.c.) was administered every 12 h for 5 or 15 d, and animals were killed 1 h after the last injection. KYNA levels were determined as described in Materials and Methods. Results are presented as mean ± SEM (n = 5 animals in each treatment).

^*p < 0.05 versus PBS-injected controls (repeated-measures ANOVA followed by Bonferroni's post hoctest for multiple comparisons).