Amphetamine-treatment groups for P-ERK1/2 analyses
| Days 1-5 | Day 6 | ||
|---|---|---|---|
| Group | Pretreatment | First injection | Second injection |
| Acute amphetamine group | |||
| Saline (Chr SAL, SAL) | Saline | Saline | Saline |
| Acute DILT (Chr SAL, DILT) | Saline | Diltiazem | Saline |
| Acute AMPH (Chr SAL, AMPH) | Saline | Saline | Amphetamine |
| DILT plus acute AMPH (Chr SAL, DILT + AMPH) | Saline | Diltiazem | Amphetamine |
| Chronic amphetamine group | |||
| Saline (Chr AMPH, SAL) | Amphetamine | Saline | Saline |
| AMPH (Chr AMPH, AMPH) | Amphetamine | Saline | Amphetamine |
| DILT plus AMPH (Chr AMPH, DILT + AMPH) | Amphetamine | Diltiazem | Amphetamine |
| DILT plus SAL (Chr AMPH, DILT + SAL) | Amphetamine | Diltiazem | Saline |
Rats from all groups were given intraperitoneal injections of saline or amphetamine on days 1-5. On day 6, injection 1 was given 20 min before injection 2. AMPH, d-amphetamine sulfate, 5 mg/kg salt; DILT, diltiazem, 30 or 60 mg/kg.