Measures of K1 and DAT availability in controls and methamphetamine abusers evaluated during short or protracted abstinence
| Controls (n = 11) | METH abusers (short abstinence) (n = 12) | METH abusers (protracted abstinence) (n = 10) | |
|---|---|---|---|
| K1 | |||
| Cerebellum | 0.42 ± 0.11 | 0.48 ± 0.17 | 0.46 ± 0.11 |
| Caudate | 0.58 ± 0.12 | 0.63 ± 0.18 | 0.55 ± 0.07 |
| Putamen | 0.64 ± 0.14 | 0.73 ± 0.24 | 0.62 ± 0.08 |
| Bmax/Kd | |||
| Caudate | 1.76 ± 0.27 | 1.32 ± 0.28* | 1.67 ± 0.291-160 |
| Putamen | 1.97 ± 0.21 | 1.56 ± 0.30* | 1.80 ± 0.35 |
The K1 (transfer constant of [11C]d-threo-methylphenidate from plasma to brain) and Bmax/Kd(measure of DAT availability) were measured in 11 controls, 12 METH abusers evaluated during short abstinence (64 ± 40 d of abstinence), and 10 METH abusers evaluated during protracted abstinence (15 ± 7 months of abstinence). Note that the data for the five METH abusers tested twice was included in this group analysis: the data obtained during the first evaluation as part of the group tested during short abstinence and the data obtained during the second evaluation as part of the group tested during protracted abstinence. Factorial ANOVA showed that the group differences were significant forBmax/Kd in caudate (p < 0.002) and putamen (p < 0.01).Post hoc t tests;
↵* p < 0.003, different from controls;
↵F1-160 p < 0.01, different from short abstinence.