Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intravenous desmopressin, a synthetic antidiuretic hormone, resulted in a dose-dependent increase in intraocular pressure (IOP) in rabbits. IOP was increased 3.6 +/- 0.8 mm Hg 6 hr following injection of desmopressin 200 mUnits/kg with the increase lasting over 10 hr. IOP returned to baseline 24 hr after the injection. Systemic blood pressure, plasma osmolarity and arterial blood gases were not altered by desmopressin. The increased IOP was not associated with alterations in measured outflow facility or episcleral venous pressure. Five hours after desmopressin injection, calculated aqueous humor flow was increased approximately 57%. Aqueous humor ascorbate measurements for calculation of flow to diffusion ratios and anterior chamber fluorophotometry also were consistent with an increased rate of aqueous humor formation as the mechanism for the IOP elevation. Desmopressin administration did not increase aqueous humor protein or aqueous humor cyclic AMP concentration. Systemic pretreatment with indomethacin only partially blocked the IOP increase. Systemic pretreatment with demeclocycline completely blocked the desmopressin-induced increase in IOP.
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PMID:Effects of systemic desmopressin on aqueous humor dynamics in rabbits. 283 Feb 1

Rabbits subjected to free-floating body immersion demonstrated decreases in intraocular pressure followed by later increases. These intraocular pressure alterations were associated with parallel changes in aqueous humor production. Episcleral venous pressure was elevated during immersion but outflow facility was unaltered. The decrease in intraocular pressure could be partially blocked by pretreatment with vasopressin or desoxycorticosterone acetate. In cross-circulation studies between an immersed and non-immersed rabbit, a decrease in intraocular pressure was observed in both animals. This observation further supported the involvement of humoral factors in the body-immersion induced intraocular pressure response.
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PMID:The effects of body immersion on aqueous humor dynamics in rabbits. 670 46

The rate of aqueous humor flow was studied in 17 human subjects with neurogenic diabetes insipidus. Flow was measured by fluorophotometry on two consecutive afternoons. The first day, subjects used desmopressin to control their diuresis; on the second day, subjects did not use desmopressin and had uncontrolled diuresis. On both days, one eye was treated with the beta-adrenergic antagonist, timolol. With desmopressin, the rate of aqueous humor flow in the untreated eye was 2.53 +/- 0.79 microliters/min (mean +/- standard deviation) and in the timolol-treated eye was 1.69 +/- 0.40 microliters/min. Without desmopressin, the rate of aqueous humor flow in the untreated eye was 2.34 +/- 0.69 microliters/min and in the timolol-treated eye was 1.53 +/- 0.43 microliters/min. Thus, the use of desmopressin was associated with a slightly higher rate of aqueous humor flow in both the normal and the beta-adrenergically inhibited eye (P = .05), and the suppression of aqueous humor flow associated with beta-adrenergic inhibition occurred with and without antidiuretic hormone (P < .001). The observed differences in aqueous humor flow on the two days could have been caused by a direct effect on the eye or to indirect effects, such as the change in plasma osmolality, which changed from 291 +/- 6 mOsm on the desmopressin day to 299 +/- 8 mOsm on the desmopressin-abstention day (P < .001).
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PMID:Effect of desmopressin on aqueous humor flow in humans. 847 Jul 25

The effects of atrial natriuretic peptide (ANP), vasopressin (AVP) and angiotensin (ANG) on blood and intraocular pressures of pentobarbital anesthetized rats were evaluated following intravenous, intracerebroventricular or anterior chamber routes of administration. Central injections did not affect intraocular pressure. Equipressor intravenous infusions of ANG raised, whereas AVP decreased, intraocular pressure. Direct infusions of a balanced salt solution (0.175 microliter/min) raised intraocular pressure between 30 and 60 min. Adding ANG or ANP slightly reduced this solvent effect but AVP was markedly inhibitory. An AVP-V1 receptor antagonist reversed the blunting of the solvent-induced rise by the peptide, indicating receptor specificity. Acetazolamide pretreatment lowered intraocular pressure, but the solvent-induced rise in intraocular pressure and inhibition by AVP still occurred without altering the temporal pattern. Thus, these effects appear unrelated to aqueous humor synthesis rate. The data support the possibility of intraocular pressure regulation by peptides acting from the blood and aqueous humor.
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PMID:Effects of angiotensin, vasopressin and atrial natriuretic peptide on intraocular pressure in anesthetized rats. 858 37

Discovery of aquaporin water channel proteins has provided insight into the molecular mechanism of membrane water permeability. The distribution of known mammalian aquaporins predicts roles in physiology and disease. Aquaporin-1 mediates proximal tubule fluid reabsorption, secretion of aqueous humor and cerebrospinal fluid, and lung water homeostasis. Aquaporin-2 mediates vasopressin-dependent renal collecting duct water permeability; mutations or downregulation can cause nephrogenic diabetes insipidus. Aquaporin-3 in the basolateral membrane of the collecting duct provides an exit pathway for reabsorbed water. Aquaporin-4 is abundant in brain and probably participates in reabsorption of cerebrospinal fluid, osmoregulation, and regulation of brain edema. Aquaporin-5 mediates fluid secretion in salivary and lacrimal glands and is abundant in alveolar epithelium of the lung. Specific regulation of membrane water permeability will likely prove important to understanding edema formation and fluid balance in both normal physiology and disease.
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PMID:Pathophysiology of the aquaporin water channels. 881 12

The discovery of water channels (aquaporins) was a breakthrough in research on water transport. Aquaporins are a family of intrinsic membrane proteins that function as water-selective channels (except aquaporin-3 and aquaporin-7, which are permeable to urea and glycerol as well) in the plasma membranes of many cells. Aquaporin-0 (MIP26) functions to maintain fluid balance in the lens. Aquaporin-1 is involved in water reabsorption in the kidney's proximal tubules and the thin descending Henle's loop, aqueous humor formation in eye, cerebrospinal fluid formation in brain, and airway hydration in lung. Aquaporin-2 is the only water channel that is activated by vasopressin to enhance water reabsorption in the kidney collecting duct. Aquaporin-3 also contributes to water reabsorption in the kidney collecting duct but is unresponsive to vasopressin. It also appears that aquaporin-3 may contribute to cornea transparency. Aquaporin-4 is involved in cerebrospinal fluid transport in brain, water transport in the kidney collecting duct, aqueous humor transport in the eye, and airway hydration in the lung. Aquaporin-5 apparently is coupled to fluid secretion in exocrine tissues. Although the exact function of aquaporin-6 is not known due to its uncertain localization, its restricted presence in the kidney may suggest a potential role in water transport. Aquaporin-7 appears to play a role in the cryopreservation of the sperm whereas aquaporin-8 is responsible for the secretion of pancreatic juice. The major focus of this review is a discussion of aquaporins in renal epithelia, and particularly the mechanisms associated with vasopressin-mediated water transport involving aquaporin-2 and the signal transduction pathways linked to vasopressin action.
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PMID:Aquaporins (water channels): role in vasopressin-activated water transport. 982 41

The aqueous humor is produced in the ciliary body, therefore in this study we investigated the Atrial natriuretic peptide (ANP) and vasopressin (VP)-presence in the ciliary body of the pig eye since these peptide are involved in the homeostasis of body fluids. The results show ANP-presence in the epithelial cells and in the endothelial cells of the blood vessels and VP-presence in the epithelial cells, in the endothelium of canal of Schelmm and in the muscle cells of the blood vessels. These peptides might regulate the synthesis and the composition of the aqueous humor and regulate the hydrodynamic flow and haemodynamic flow of the blood.
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PMID:Atrial natriuretic peptide and vasopressin-presence in the ciliary body of eye in the pig (sus domesticus). 2500 68