A,B. There are no differences in plasmalemmal or near plasmalemmal DOR-SIG particle density between Sal- and Oxy-CIS females and males. C,D. Sal-CIS females compared to Sal-CIS males have a greater density of DOR-SIG particles in the cytoplasm (C) and in total (D) in large GABA-labeled dendrites. Sal-CIS females compared to Sal-CIS males have a greater density of DOR-SIG particles in total in small GABA-labeled dendrites (not shown). Oxy-CIS females compared to Oxy-CIS males have increased density of DOR-SIG particles in large (D) GABA-labeled dendrites. SF, Sal-female; SM, Sal-male; OF, Oxy-female; OM, Oxy-male. **p < 0.01, *p ≤ 0.05; N = 3 rats per group; n = 50 dendrites per rat.