MORIMOTO Satoshi    Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine    Position   Associate Professor
Article types	Original article
Language	English
Peer review	Peer reviewed
Title	Local production of angiotensin II in the subfornical organ causes elevated drinking.
Journal	Formal name：The Journal of clinical investigation Abbreviation：J Clin Invest ISSN code：00219738/00219738
Domestic / Foregin	Foregin
Volume, Issue, Page	117(4),pp.1088-95
Author and coauthor	Sakai Koji, Agassandian Khristofor, Morimoto Satoshi, Sinnayah Puspha, Cassell Martin D, Davisson Robin L, Sigmund Curt D
Publication date	2007/04
Summary	The mechanism controlling cell-specific Ang II production in the brain remains unclear despite evidence supporting neuron-specific renin and glial- and neuronal-specific angiotensinogen (AGT) expression. We generated double-transgenic mice expressing human renin (hREN) from a neuron-specific promoter and human AGT (hAGT) from its own promoter (SRA mice) to emulate this expression. SRA mice exhibited an increase in water and salt intake and urinary volume, which were significantly reduced after chronic intracerebroventricular delivery of losartan. Ang II-like immunoreactivity was markedly increased in the subfornical organ (SFO). To further evaluate the physiological importance of de novo Ang II production specifically in the SFO, we utilized a transgenic mouse model expressing a floxed version of hAGT (hAGT(flox)), so that deletions could be induced with Cre recombinase. We targeted SFO-specific ablation of hAGT(flox) by microinjection of an adenovirus encoding Cre recombinase (AdCre). SRA(flox) mice exhibited a marked increase in drinking at baseline and a significant decrease in water intake after administration of AdCre/adenovirus encoding enhanced GFP (AdCre/AdEGFP), but not after administration of AdEGFP alone. This decrease only occurred when Cre recombinase correctly targeted the SFO and correlated with a loss of hAGT and angiotensin peptide immunostaining in the SFO. These data provide strong genetic evidence implicating de novo synthesis of Ang II in the SFO as an integral player in fluid homeostasis.
DOI	10.1172/JCI31242
PMID	17404622