Increasing permeability of the inner medullary portion of the collecting duct to urea by regulating the cell surface expression of urea transporters, which facilitates its reabsorption into the medullary interstitium as it travels down the concentration gradient created by removing water from the connecting tubule, cortical collecting duct, and outer medullary collecting duct. Acute increase of sodium absorption across the ascending loop of Henle. This adds to the countercurrent multiplication which aids in proper water reabsorption later in the distal tubule and collecting duct. Central nervous system
Vasopressin released within the brain may have several actions:

Vasopressin is released into the brain in a circadian rhythm by neurons of the suprachiasmatic nucleus. Vasopressin released from posterior pituitary is associated with nausea. Recent evidence suggests that vasopressin may have analgesic effects. The analgesia effects of vasopressin were found to be dependent on both stress and sex. Regulation
Gene regulation
Vasopressin is regulated by AVP gene expression which is managed by major clock controlled genes. In this circadian circuit known as the transcription-translation feedback loop (TTFL), Per2 protein accumulates and is phosphorylated by CK1E. Per2 subsequently inhibits the transcription factors Clock and BMAL1 in order to reduce Per2 protein levels in the cell. At the same time, Per2 also inhibits the transcription factors for the AVP gene in order to regulate its expression, the expression of vasopressin, and other AVP gene products.Many factors influence the secretion of vasopressin:

Ethanol (alcohol) reduces the calcium-dependent secretion of AVP by blocking voltage-gated calcium channels in neurohypophyseal nerve terminals in rats.
There is some evidence that people in the creative industries have bipolar disorder more often than those in other occupations.Winston Churchill had periods of manic symptoms that may have been both an asset and a liability.English actor Stephen Fry, who has bipolar disorder, recounts manic behaviour during his adolescence: "When I was about 17 ... going around London on two stolen credit cards, it was a sort of fantastic reinvention of myself, an attempt to. I bought ridiculous suits with stiff collars and silk ties from the 1920s, and would go to the Savoy and Ritz and drink cocktails." While he has experienced suicidal thoughts, he says the manic side of his condition has had positive contributions on his life. Etymology
The nosology of the various stages of a manic episode has changed over the decades. The word derives from the Ancient Greek μανία (manía), "madness, frenzy" and the verb μαίνομαι (maínomai), "to be mad, to rage, to be furious". See also
References
Further reading
Expert Opin Pharmacother. 2001 December;2(12):1963–73. Schizoaffective Disorder. 2007 September Mayo Clinic. Retrieved October 1, 2007. Schizoaffective Disorder Archived 2011-08-18 at the Wayback Machine. 2004 May. All Psych Online: Virtual Psychology Classroom. Retrieved October 2, 2007. Psychotic Disorders. 2004 May. All Psych Online: Virtual Psychology Classroom. Retrieved October 2, 2007. Sajatovic, Martha; DiBiovanni, Sue Kim; Bastani, Bijan; Hattab, Helen; Ramirez, Luis F. (1996). "Risperidone therapy in treatment refractory acute bipolar and schizoaffective mania". Psychopharmacology Bulletin. 32 (1): 55–61. PMID 8927675. External links

Bipolar Mania Symptoms
Depression and Bipolar Support Alliance