Table 3.
D2 receptor binding in juvenile rats (PD 42) after three weeks of daily administration of risperidone
| Brain region | Controls | RSP(0.3 mg/kg) | Juvenile Rats RSP(1.0 mg/kg) | RSP(3.0 mg/kg) | Adult Rats RSP(3.0 mg/kg) |
|---|---|---|---|---|---|
| Cerebral cortex | |||||
| Medial-prefrontal | 36.4 ± 1.6 (100) | 44.1 ± 1.1 (121)* | 51.4 ± 1.5(141)* | 56.5 ± 3.5 (155)* | (134)* |
| Dorsolateral | 30.3 ± 6.0 (100) | 28.8 ± 4.2 (95) | 34.3 ± 2.3 (113) | 35.5 ± 3.4 (117) | (91) |
| Nucleus accumbens | 157 ± 3.6 (100) | 156 ± 1.6 (99) | 192 ± 2.8 (122)* | 213 ± 3.4 (136)* | (128)* |
| Caudate-putamen | |||||
| Medial | 153 ± 6.2 (100) | 160 ± 4.2(105) | 180 ± 4.5 (118) | 214 ± 5.5 (140)* | (127)* |
| Lateral | 223 ± 4.8 (100) | 227 ± 4.4 (102) | 261 ± 5.2 (117) | 299 ± 4.2 (134)* | (123)* |
| Hippocampus | 37.2 ± 1.6 (100) | 46.0 ± 1.4 (124)* | 58.5 ± 3.3 (157)* | 70.5 ± 2.7 (190)* | (130)* |
Data are mean ± SEM values for binding (fmol/mg tissue, [% of control]), determined by quantitative autoradiography following daily i.p. injection of vehicle or risperidone (RSP) for 3 weeks, with significant differences from controls indicated in bold ([*] p<0.05, N=6 rats/group). Data (% of control) for RSP (3 mg/kg/d) in adult animals were reported previously (Tarazi et al., 2001) and are shown for comparison.