Methods: 1.The immune cell chemical method(SABC) is adopted, and all NOS positive neurons of SON PVN and LHA can be tested on cell count and observed morphologically under light microscope;2.

• 方法：1．采用SABC法，在光学显微镜下对下丘脑室旁核(PVN)、视上核(SON)和下丘脑外侧区(LHA)内NOS阳性神经元进行形态观察和细胞计数；