Few studies have described ER stress responses in MCNs of hypothalamus under physiological conditions [23], but ER stress is believed to be involved in the pathogenesis of familial neurohypophyseal diabetes insipidus (FNDI), a progressive neurodegenerative disease caused by mutations of AVP gene which results in symptoms of polyuria and polydipsia [32, 33]. Here, AVP is linked to Polyuria.