Figure 2.

Stressor Controllability and Central Benzodiazapine/GABA_A receptor. Top: Rats were exposed to ES, IS, or no stress, and then administered increasing doses of bicuculline 2 h after stress. Rats with prior ES appeared to be protected from seizures with a significant delay in the onset of clonus seizure symptoms compared to unstressed rats [ES had a significantly longer latency compared to no stress controls (^*p < 0.05). Adapted from Drugan et al., 1985c]. Middle: Mean (+SEM) [³⁵S]TBPS receptor binding (2 nM, fmol/mg protein brain tissue) 2 h after stress. Exposure to ES significantly reduced competitive binding of the benzodiazepine receptor ligand (^*p < 0.05, adapted from Drugan et al., 1994). Bottom: Mean (+SEM) brain levels of benzodiazepine receptor agonist molecules (ng/mg brain tissue) 2 h after stress. Prior ES significantly increased levels of endogenous benzodiazepine receptor ligands (^*p < 0.05, adapted from Drugan et al., 1994).