Ohno Akitoshi, Ohya Susumu, Yamamura Hisao, Imaizumi Yuji
Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Mizuhoku, Nagoya, Japan.
Biochem Biophys Res Commun. 2009 Jan 23;378(4):867-71. doi: 10.1016/j.bbrc.2008.12.004. Epub 2008 Dec 12.
The expression of large-conductance Ca(2+)-activated K(+) (BK) channel protein in amygdala complex was higher in adult (8-10 weeks old) male rats than in female. Castration at 4-6 weeks old significantly reduced BK channel expression in amygdala to the level similar to that in female. Immunocytochemical analyses of pyramidal-like neurons isolated from amygdala revealed that somas with relatively large size were highly immunoreactive to both anti-androgen receptor (AR) and anti-BK channel antibodies, while those with smaller size were not. The double-immunopositive neurons were dominant (60%) among pyramidal-like neurons isolated from amygdala of male rats but rare among those from female. The membrane current sensitive to penitrem A, a BK channel blocker, was the major K(+) current component in large neurons and showed higher current-density than that in smaller ones. These results suggest the gender-dependent cell population expressing BK channels in amygdala complex and its up-regulation by AR stimulation.
在杏仁核复合体中，大电导钙激活钾（BK）通道蛋白在成年（8 - 10周龄）雄性大鼠中的表达高于雌性。4 - 6周龄时去势显著降低了杏仁核中BK通道的表达，使其降至与雌性相似的水平。对从杏仁核分离出的锥体细胞样神经元进行免疫细胞化学分析发现，相对较大的细胞体对抗雄激素受体（AR）抗体和抗BK通道抗体均具有高度免疫反应性，而较小的细胞体则无此反应。在从雄性大鼠杏仁核分离出的锥体细胞样神经元中，双免疫阳性神经元占主导（60%），而在雌性大鼠中则很少见。对BK通道阻滞剂青霉震颤素A敏感的膜电流是大神经元中主要的钾电流成分，且其电流密度高于小神经元。这些结果表明，杏仁核复合体中表达BK通道的细胞群体存在性别差异，且AR刺激可使其上调。
