Sex Difference and Testosterone Modulation: RESULTS(3)

17 Mar
2013

Statistical analyses revealed a significant sex X odor stimulus interaction (F = 9.088, p < 0.01) as well as a significant steroid treatment X odor stimulus interaction (F = 5.815, p < 0.01).

to augment neuronal Fos-IR in any of the subregions of the POA, and estrous odors failed to affect neuronal Fos-IR in either the dPOA/AH or vPOA/AH (Fig. 5, middle and bottom panels). buy yasmin online

Androgen receptor-IR was present in the MOB and AOB in both sexes. Immunopositive cells were primarily restricted to the granule and mitral cell layers of the MOB and to the cell layer of the AOB (Fig. 6) in all five animals studied. By contrast, ER-IR was not seen anywhere in the MOB or AOB of any of the five ferrets studied for this purpose (Fig. 6). Both AR-IR and ER-IR were present in the mPOA, as expected from previous reports in the ferret.

Experiment 2: Neuronal Fos-IR Responses in the Chemosensory Pathway after Exposure to Soiled Bedding from a Male in Breeding Condition

Pheromones from soiled male bedding caused significant increases in neuronal Fos-IR in all three regions of the MOB in gonadectomized, TP-treated male and female ferrets (Table 1). As with estrous female odors (experiment 1), exposure to male odors failed to influence neuronal Fos-IR in the AOB of either sex. Exposure to male odors also caused significant increases in neuronal Fos-IR in the MA of both male and female subjects. Statistical analyses revealed significant effects of odor stimulus in the rostral MOB (F = 3.531, p < 0.05), central MOB (F = 3.462, p < 0.05), and caudal MOB (F = 8.993, p < 0.01) in addition to the MA (F = 18.108, p < 0.01).
Fig6Sex Difference and Testosterone
FIG. 6. Representative photomicrographs of AR-IR (left) in a gonadecto-mized, TP-treated female, and ER-IR (right) in a gonadectomized, oil-treated female ferret. The top two panels show examples of AR-IR and ER-IR, respectively, in the mPOA. The middle and bottom panels show AR-IR in the AOB (middle left) and MOB (bottom left), but no ER-IR in the AOB (middle right) or the MOB (bottom right). GL, glomerular layer; EPL, external plexiform layer; MCL, mitral cell layer; GCL, granule cell layer; CL, AOB cell layer.

Fig7Sex Difference and Testosterone
FIG. 7. Schematic representation of the observed sex differences (experiments 1 and 2) in the ability of the pheromones derived from soiled bedding of an estrous female or a breeding male to augment neuronal Fos-IR in different segments of the chemosensory projection pathway of gonadectomized, TP-treated male and female ferrets. Sexually dimorphic responses to both female and male pheromones occurred only in the central segments of the pathway (i.e., BNST, mPOA, and VLH), with females being more responsive than males. Black shading designates brain regions in which maximal neuronal Fos induction occurred. Gray shading designates a brain region (BNST) in which male subjects had significantly more neuronal Fos-IR than clean-cage controls but significantly less neuronal Fos-IR than female subjects. Unshaded regions designate brain regions in which pheromone-exposed ferrets had the same number of Fos-IR cells as clean-cage controls.

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