Limits...
Regional difference in sex steroid action on formation of morphological sex differences in the anteroventral periventricular nucleus and principal nucleus of the bed nucleus of the stria terminalis.

Kanaya M, Tsuda MC, Sagoshi S, Nagata K, Morimoto C, Thu CK, Toda K, Kato S, Ogawa S, Tsukahara S - PLoS ONE (2014)

Bottom Line: The volume and neuron number of the male BNSTp were smaller in ARKO mice than those in wild-type mice, while no significant effect of ARKO was found on the AVPV and female BNSTp.In the AVPV, the aromatase mRNA level was higher on ED18, although the ERα mRNA level was higher on PD4 without any effect of AR gene deletion.Aromatase and ERα mRNA levels in the male BNSTp were significantly increased on PD4 by AR gene deletion.

View Article: PubMed Central - PubMed

Affiliation: Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.

ABSTRACT
Sex steroid action is critical to form sexually dimorphic nuclei, although it is not fully understood. We previously reported that masculinization of the principal nucleus of the bed nucleus of the stria terminalis (BNSTp), which is larger and has more neurons in males than in females, involves aromatized testosterone that acts via estrogen receptor-α (ERα), but not estrogen receptor-β (ERβ). Here, we examined sex steroid action on the formation of the anteroventral periventricular nucleus (AVPV) that is larger and has more neurons in females. Morphometrical analysis of transgenic mice lacking aromatase, ERα, or ERβ genes revealed that the volume and neuron number of the male AVPV were significantly increased by deletion of aromatase and ERα genes, but not the ERβ gene. We further examined the AVPV and BNSTp of androgen receptor knockout (ARKO) mice. The volume and neuron number of the male BNSTp were smaller in ARKO mice than those in wild-type mice, while no significant effect of ARKO was found on the AVPV and female BNSTp. We also examined aromatase, ERα, and AR mRNA levels in the AVPV and BNSTp of wild-type and ARKO mice on embryonic day (ED) 18 and postnatal day (PD) 4. AR mRNA in the BNSTp and AVPV of wild-type mice was not expressed on ED18 and emerged on PD4. In the AVPV, the aromatase mRNA level was higher on ED18, although the ERα mRNA level was higher on PD4 without any effect of AR gene deletion. Aromatase and ERα mRNA levels in the male BNSTp were significantly increased on PD4 by AR gene deletion. These results suggest that estradiol signaling via ERα during the perinatal period and testosterone signaling via AR during the postnatal period are required for masculinization of the BNSTp, whereas the former is sufficient to defeminize the AVPV.

Show MeSH

Related in: MedlinePlus

Representative photomicrographs of the AVPV in adult mice.Photomicrographs show WT male and female mice. Dotted lines indicate the border areas of the AVPV. Scale bars indicate 100 µm. oc, optic chiasm; 3V, third ventricle.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4232352&req=5

pone-0112616-g001: Representative photomicrographs of the AVPV in adult mice.Photomicrographs show WT male and female mice. Dotted lines indicate the border areas of the AVPV. Scale bars indicate 100 µm. oc, optic chiasm; 3V, third ventricle.

Mentions: In WT littermates of transgenic mice lacking aromatase, ERα, ERβ, or AR genes, the AVPV was larger and had more neuronal cell bodies in female mice than that in male mice (Figure 1). The morphology of the AVPV in male mice, but not female mice, was affected by deletion of aromatase and ERα genes, whereas there was no significant effect of ERβ and AR gene deletions. The volume of the AVPV in AromKO males and the volume and neuron number of the AVPV in αERKO males were significantly greater than those in WT males (Figure 2A, 2C, and 2D). In addition, the neuron number of the male AVPV was increased in mice lacking the aromatase gene. The neuron number of the AVPV was significantly higher in AromKO mice than that in WT mice and higher in female mice than that in male mice (Figure 2B). The volume and neuron number of the AVPV were greater in female mice than those in male mice despite the lack of ERβ and AR genes (Figure 2E–2H). The density of AVPV neurons did not differ significantly between sexes and was unaffected by deletion of ERα, ERβ, or AR genes, although it was significantly higher in female mice and transgenic mice among AromKO and WT mice (Tables S1–S4). The number of glial cells in the AVPV was not altered by sex or deletion of ERα or ERβ genes (Tables S2 and S3). On the other hand, deletion of the aromatase gene resulted in a significant increase in the glial cell number of the AVPV (Table S1). The glial cell number in the AVPV was significantly higher in WT and ARKO female mice than that in WT and ARKO male mice (Table S4). The density of glial cells in the AVPV was not changed by sex or deletion of any gene.


Regional difference in sex steroid action on formation of morphological sex differences in the anteroventral periventricular nucleus and principal nucleus of the bed nucleus of the stria terminalis.

Kanaya M, Tsuda MC, Sagoshi S, Nagata K, Morimoto C, Thu CK, Toda K, Kato S, Ogawa S, Tsukahara S - PLoS ONE (2014)

Representative photomicrographs of the AVPV in adult mice.Photomicrographs show WT male and female mice. Dotted lines indicate the border areas of the AVPV. Scale bars indicate 100 µm. oc, optic chiasm; 3V, third ventricle.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4232352&req=5

pone-0112616-g001: Representative photomicrographs of the AVPV in adult mice.Photomicrographs show WT male and female mice. Dotted lines indicate the border areas of the AVPV. Scale bars indicate 100 µm. oc, optic chiasm; 3V, third ventricle.
Mentions: In WT littermates of transgenic mice lacking aromatase, ERα, ERβ, or AR genes, the AVPV was larger and had more neuronal cell bodies in female mice than that in male mice (Figure 1). The morphology of the AVPV in male mice, but not female mice, was affected by deletion of aromatase and ERα genes, whereas there was no significant effect of ERβ and AR gene deletions. The volume of the AVPV in AromKO males and the volume and neuron number of the AVPV in αERKO males were significantly greater than those in WT males (Figure 2A, 2C, and 2D). In addition, the neuron number of the male AVPV was increased in mice lacking the aromatase gene. The neuron number of the AVPV was significantly higher in AromKO mice than that in WT mice and higher in female mice than that in male mice (Figure 2B). The volume and neuron number of the AVPV were greater in female mice than those in male mice despite the lack of ERβ and AR genes (Figure 2E–2H). The density of AVPV neurons did not differ significantly between sexes and was unaffected by deletion of ERα, ERβ, or AR genes, although it was significantly higher in female mice and transgenic mice among AromKO and WT mice (Tables S1–S4). The number of glial cells in the AVPV was not altered by sex or deletion of ERα or ERβ genes (Tables S2 and S3). On the other hand, deletion of the aromatase gene resulted in a significant increase in the glial cell number of the AVPV (Table S1). The glial cell number in the AVPV was significantly higher in WT and ARKO female mice than that in WT and ARKO male mice (Table S4). The density of glial cells in the AVPV was not changed by sex or deletion of any gene.

Bottom Line: The volume and neuron number of the male BNSTp were smaller in ARKO mice than those in wild-type mice, while no significant effect of ARKO was found on the AVPV and female BNSTp.In the AVPV, the aromatase mRNA level was higher on ED18, although the ERα mRNA level was higher on PD4 without any effect of AR gene deletion.Aromatase and ERα mRNA levels in the male BNSTp were significantly increased on PD4 by AR gene deletion.

View Article: PubMed Central - PubMed

Affiliation: Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.

ABSTRACT
Sex steroid action is critical to form sexually dimorphic nuclei, although it is not fully understood. We previously reported that masculinization of the principal nucleus of the bed nucleus of the stria terminalis (BNSTp), which is larger and has more neurons in males than in females, involves aromatized testosterone that acts via estrogen receptor-α (ERα), but not estrogen receptor-β (ERβ). Here, we examined sex steroid action on the formation of the anteroventral periventricular nucleus (AVPV) that is larger and has more neurons in females. Morphometrical analysis of transgenic mice lacking aromatase, ERα, or ERβ genes revealed that the volume and neuron number of the male AVPV were significantly increased by deletion of aromatase and ERα genes, but not the ERβ gene. We further examined the AVPV and BNSTp of androgen receptor knockout (ARKO) mice. The volume and neuron number of the male BNSTp were smaller in ARKO mice than those in wild-type mice, while no significant effect of ARKO was found on the AVPV and female BNSTp. We also examined aromatase, ERα, and AR mRNA levels in the AVPV and BNSTp of wild-type and ARKO mice on embryonic day (ED) 18 and postnatal day (PD) 4. AR mRNA in the BNSTp and AVPV of wild-type mice was not expressed on ED18 and emerged on PD4. In the AVPV, the aromatase mRNA level was higher on ED18, although the ERα mRNA level was higher on PD4 without any effect of AR gene deletion. Aromatase and ERα mRNA levels in the male BNSTp were significantly increased on PD4 by AR gene deletion. These results suggest that estradiol signaling via ERα during the perinatal period and testosterone signaling via AR during the postnatal period are required for masculinization of the BNSTp, whereas the former is sufficient to defeminize the AVPV.

Show MeSH
Related in: MedlinePlus