Species differences in the density of TH-ir cells in brain areas.

<p>(A) Species differences in the density of TH-ir cells in the anterior hypothalamus (AH), lateral hypothalamus (LH), medial preoptic area (MPOA), paraventricular nucleus of the hypothalamus (PVN), ventral tegmental area (VTA) and substantianigra pars compacta (SNc). (B) Species differences in the density of TH-ir cells in the anterior (MPOAa), intermediate (MPOAi) and posterior (MPOAp) subnuclei of the MPOA. (C) Student-Newman-Keuls (SNK) post hoc test indicated differences in the lateral hypothalamus (LH) between males and females of the two species (MG: Monglian gerbil; CH: Chinese striped hamster; M: male; F: female). Bars with different alphabetic letters differed significantly from each other. * <i>p</i><0.05, ** <i>p</i><0.01.</p

Density of TH immunoreactive cells (mean±SEM/mm²) in the brain of male and female Mongolian gerbils and Chinese striped hamsters.

<p>SEM: standard error of the mean;</p>*<p><i>p</i><0.05;</p>**<p><i>p</i><0.01;</p><p>ns, not significantly different.</p

Species differences in the density of OT-ir cells in brain areas.

<p>(A) Species differences in the density of OT-ir cells in the anterior hypothalamus (AH), lateral hypothalamus (LH) and medial preoptic area (MPOA). (B) The two species also differed in the density of OT-ir cells in the subnuclei of the MPOA, including the anterior (MPOAa), intermediate (MPOAi) and posterior (MPOAp) part of the MPOA. (C) Species difference in the density of OT-ir cells in the paraventricular nucleus of the hypothalamus (PVN). ** <i>p</i><0.01.</p

Species differences in the density of ERα-ir cells in brain areas.

<p>(A) Species differences in the density of ERα-ir cells in the anterior hypothalamus (AH), bed nucleus of the striaterminalis (BST), medial preoptic area (MPOA), lateral septum (LS), ventral medial hypothalamus (VMH), arcuate nucleus of the hypothalamus (ARC), medial nucleus (MeA) and anterior cortical nucleus (CoA) of the amygdala and paraventricular nucleus of the hypothalamus (PVN). ** <i>p</i><0.01.</p

Species differences in the density of AVP-ir cells in brain areas.

<p>(A) Species differences in the density of AVP-ir cells in the anterior hypothalamus (AH), lateral hypothalamus (LH) and medial preoptic area (MPOA). (B) The two species also differed in the density of AVP-ir cells in the subnuclei of the MPOA, including the anterior (MPOAa), intermediate (MPOAi) and posterior (MPOAp) part of the MPOA. (C) A species difference was also found in the paraventricular nucleus of the hypothalamus (PVN). * <i>p</i><0.05, ** <i>p</i><0.01.</p

Neurochemical implications in social behaviors.

<p>↑: increase and↓: decrease in behavior.</p

Density of ERα immunoreactive cells (mean±SEM/mm²) in the brain of male and female Mongolian gerbils and Chinese striped hamsters.

<p>SEM: standard error of the mean;</p>**<p><i>p</i><0.01;</p><p>ns, not significantly different.</p

Photomicrographs of neuropeptides expression in the posterior subnucleus of the medial preoptic area (MPOAp).

<p>Photomicrographs displaying OT-ir (A & B), AVP-ir (C & D), TH-ir (E & F) and ERα-ir (G & H) stained cells in the posterior subnucleus of the medial preoptic area (MPOAp) in the brains of Mongolian gerbils (A, C, E & G) and Chinese striped hamsters (B, D, F & H). 3V, third ventricle, Scale bar = 100 µm.</p

Density of vasopressin immunoreactive cells (mean±SEM/mm²) in the brain of male and female Mongolian gerbils and Chinese striped hamsters.

<p>SEM: standard error of the mean;</p>*<p><i>p</i><0.05;</p>**<p><i>p</i><0.01;</p><p>ns, not significantly different.</p

Photomicrographs of neuropeptides expression in the anterior subnucleus of the medial preoptic area (MPOAa).

<p>Photomicrographs displaying OT-ir (A & B), AVP-ir (C & D), TH-ir (E & F) and ERα-ir (G & H) stained cells in the anterior subnucleus of the medial preoptic area (MPOAa) in the brains of Mongolian gerbils (A, C, E & G) and Chinese striped hamsters (B, D, F & H). Scale bar = 100 µm.</p