Fig. 6.

All DAMGO effects are abolished in the presence of the μ-opioid antagonist CTAP: mean amplitudes of evoked responses (A) and PPRs (B) from 5 neurons recorded under MOR receptor blockade accomplished by adding 1 μM CTAP to a bathing solution containing normal ACSF with gabazine (5 μM) and strychnine (5 μM). Under these conditions, no significant change in the amplitude of the evoked response or PPR was observed when 0.3 μM DAMGO was added, indicating that DAMGO effects in the absence of CTAP blockade were specifically mediated by MORs.