Sex-specific alterations in mitochondrial dynamics following cohabitation with an opposite-sex partner in prairie voles. Measurement of genomic DNA (gDNA) copy number for the mitochondrial genes Nd1 (A) and Nd4l (B) in the nucleus accumbens of male and female prairie voles cohabitated with a same-sex littermate (SN), or an opposite-sex partner for 24 hrs (24H) or 3 weeks (3W). Each measurement was normalized to the nuclear gene Gapdh and depicted as a percentage of controls with the “Males SN” set as 100%. In addition, normalized mRNA levels for the fusion-promoting genes Mfn1 (C) and Mfn2 (D), as well as the fission-promoting genes Fis1 (E) and Dnm1l (F) are depicted. In all panels, each dot represents an individual vole. *p < 0.05 vs. SN group within same sex; #p < 0.05, ##p < 0.01 vs. same cohabitation group in males, Sidak’s or Tukey’s post-hoc tests.