Fos proteins are not prerequisite for osmotic induction of vasopressin transcription in supraoptic nucleus of rats

▶ Fos proteins expressed in the SON after an osmotic stimulus could bind to the promoter of AVP gene. ▶ The peak of AVP gene transcription after an osmotic stimulus preceded the expression of Fos proteins in the SON. ▶ Fos proteins are not prerequisite for the induction of AVP gene transcription.