Table 1. Schedule of experiments.
| Group | Day-1 | Day-21 | Day-26 | Day-27 | Day-28 |
|---|---|---|---|---|---|
| Untreated controls (Veh, n=20) | Ovariectomy, Placebo pellet implantation | Fresh placebo pellet implantation | -- | Inescapable stress (n=3) Sham stress (n=3) | Synapse sampling |
| Inescapable Stress (n=14) | Active escape t e sting + hormone sampling | ||||
| Hormone-withdrawn ‘postpartum’ females (PpD, n=20) | Ovariectomy, Estradiol + Progesterone pellet implantation | Switch to placebo pellet | -- | Inescapable stress (n=3) Sham stress (n=3) | Synapse sampling |
| Inescapable Stress (n=14) | Active escape testing + hormone sampling | ||||
| Simulated proestrus animals (ProE, n=16) | Ovariectomy, Placebo pellet implantation | Fresh placebo pellet implantation | 3 mg/kgestradiolbenzoate (8:30a.m.) 4 mg/kgestradiolbenzoate (8:30p.m.) | Hormone injection* + inescapable stress (n=3) Hormone injection* + sham stress (n=3) | Synapse sampling |
| Hormone injection* + inescapable stress (n=10) | Active escape testing + hormone sampling | ||||
| Hormone-treated ‘postpartum’ rats (Horm, n=20) | Ovariectomy, Estradiol + Progesterone pellet implantation | Fresh Estradiol + Progesterone pellet implantation | -- | Inescapable stress (n=3) Sham stress (n=3) | Synapse sampling |
| Inescapable Stress (n=14) | Active escape testing + hormone sampling |
*
Hormone injection = 2 mg/kg progesterone (5 h prior to stress) and 3 μg/kg 17β-estradiol (2 h prior to stress)