Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
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Target Concepts:
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Query: UNIPROT:P01185 (
vasopressin
)
23,126
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Exposure of an organism to stress leads to activation of the sympatho-adrenomedullary system and the hypothalamo-pituitary-adrenal axis. Consequently, levels of noradrenaline, peptides like
vasopressin
and CRH, and corticosteroid hormones in the brain rise. These hormones affect brain function at those sites where receptors are enriched, like the hippocampus, lateral septum, amygdala nuclei, and prefrontal cortex. During the initial phase of the stress response, when hormone levels are high, these compounds mostly enhance excitability and promote long-term potentiation. Later on, when hormone levels have subsided but gene-mediated effects of corticosteroids start to appear, the excitability is normalized to the pre-stress level, in the CA1 hippocampal area, but possibly less so in the dentate gyrus and amygdala. A
disturbed balance
between these early and late phases of the stress response as well as a shift toward the relative contribution of the dentate/amygdala pathways may explain why the normal restorative capacity fails in vulnerable people experiencing a life-threatening situation, which could contribute to the development of PTSD.
...
PMID:Stress-induced changes in hippocampal function. 1803 3
Hyperactivity of corticotropin-releasing factor (CRF) neurons in the paraventricular nucleus (PVN) of the hypothalamus is a prominent feature in depression and may be important in the etiology of this disease. The activity of the CRF neurons in the stress response is modulated by a number of factors that stimulate or inhibit CRF expression, including (1) corticosteroid receptors and their chaperones, heat shock proteins 70 and 90, (2) sex hormone receptors, (3) CRF receptors 1 (CRFR1) and 2, (4) cytokines interleukin 1-beta and tumor necrosis factor-alpha, (5) neuropeptides and receptors,
vasopressin
(AVP), AVP receptor 1a (AVPR1A) and oxytocin and (6) transcription factor cAMP-response element-binding protein. We hypothesized that, in depression, the transcript levels of those genes that are involved in the activation of the hypothalamo-pituitary-adrenal (HPA) axis are upregulated, whereas the transcript levels of the genes involved in the inhibition of the HPA axis are downregulated. We performed laser microdissection and real-time PCR in the PVN and as a control in the supraoptic nucleus. Snap-frozen post-mortem hypothalami of seven depressed and seven matched controls were used. We found significantly increased CRF mRNA levels in the PVN of the depressed patients. This was accompanied by a significantly increased expression of four genes that are involved in the activation of CRF neurons, that is, CRFR1, estrogen receptor-alpha, AVPR1A and mineralocorticoid receptor, while the expression of the androgen receptor mRNA involved in the inhibition of CRF neurons was decreased significantly. These findings raise the possibility that a
disturbed balance
in the production of receptors may contribute to the activation of the HPA axis in depression.
...
PMID:Gene expression analysis in the human hypothalamus in depression by laser microdissection and real-time PCR: the presence of multiple receptor imbalances. 1860 75
1. The kidneys are the key organs to maintain the balance of the different electrolytes in the body and the acid-base balance. Progressive loss of kidney function results in a number of adaptive and compensatory renal and extrarenal changes that allow homeostasis to be maintained with glomerular filtration rates in the range of 10-25 ml/min. With glomerular filtration rates below 10 ml/min, there are almost always abnormalites in the body's internal environment with clinical repercussions. 2. Water
Balance Disorders
: In advanced chronic kidney disease (CKD), the range of urine osmolality progressively approaches plasma osmolality and becomes isostenuric. This manifests clinically as symptoms of nocturia and polyuria, especially in tubulointerstitial kidney diseases. Water overload will result in hyponatremia and a decrease in water intake will lead to hypernatremia. Routine analyses of serum Na levels should be performed in all patients with advanced CKD (Strength of Recommendation C). Except in edematous states, a daily fluid intake of 1.5-2 liters should be recommended (Strength of Recommendation C). Hyponatremia does not usually occur with glomerular filtration rates above 10 ml/min (Strength of Recommendation B). If it occurs, an excessive intake of free water should be considered or nonosmotic release of
vasopressin
by stimuli such as pain, anesthetics, hypoxemia or hypovolemia, or the use of diuretics. Hypernatremia is less frequent than hyponatremia in CKD. It can occur because of the provision of hypertonic parenteral solutions, or more frequently as a consequence of osmotic diuresis due to inadequate water intake during intercurrent disease, or in some circumstance that limits access to water (obtundation, immobility). 3. Sodium
Balance Disorders
: In CKD, fractional excretion of sodium increases so that absolute sodium excretion is not modified until glomerular filtration rates below 15 ml/min (Strength of Recommendation B). Total body content of sodium is the main determinant of extracellular volume and therefore disturbances in sodium balance will lead to clinical situations of volume depletion or overload: Volume depletion due to renal sodium loss occurs in abrupt restrictions of salt intake in advanced CKD. It occurs more frequently in certain tubulointerstitial kidney diseases (salt losing nephropathies). Volume overload due to sodium retention can occur with glomerular filtration rates below 25 ml/min and leads to edema, arterial hypertension and heart failure. The use of diuretics in volume overload in CKD is useful to force natriuresis (Strength of Recommendation B). Thiazides have little effect in advanced CKD. Loop diuretics are effective and should be used in higher than normal doses (Strength of Recommendation B). The combination of thiazides and loop diuretics can be useful in refractory cases (Strength of Recommendation B). Weight and volume should be monitored regularly in the hospitalized patient with CKD (Strength of Recommendation C). 4. Potassium
Balance Disorders
: In CKD, the ability of the kidneys to excrete potassium decreases proportionally to the loss of glomerular filtration. Stimulation of aldosterone and the increase in intestinal excretion of potassium are the main adaptive mechanisms to maintain potassium homeostasis until glomerular filtration rates of 10 ml/min. The main causes of hyperkalemia in CKD are the following: Use of drugs that alter the ability of the kidneys to excrete potassium: ACEIs, ARBs, NSAIDs, aldosterone antagonists, nonselective beta-blockers, heparin, trimetoprim, calcineurin inhibitors. Determination of serum potassium two weeks after the initiation of treatment with ACEIs/ARBs is recommended (Strength of Recommendation C). Routine use of aldosterone antagonists in advanced CKD is not recommended (Strength of Recommendation C). Abrupt reduction in glomerular filtration rate: Constipation. Prolonged fasting. Metabolic acidosis. A low-potassium diet is recommended with GFR less than 20 ml/min, or GFR less than 50 ml/min if drugs that raise serum potassium are taken (Strength of Recommendation C). In the absence of symptoms or electrocardiographic abnormalities, review of medications, restriction of dietary potassium and use of oral ion exchange resins are usually sufficient therapeutic measures (Strength of Recommendation C). If symptoms and/or electrocardiographic abnormalities are present, the usual parenteral pharmacological measures should be used (10% calcium gluconate, insulin and glucose, salbutamol, resins, diuretics) (Strength of Recommendation A). Parenteral bicarbonate and ion exchange resins in enemas are not recommended as first-line treatment (Strength of Recommendation C). Hemodialysis should be considered in patients with glomerular filtration rates below 10 ml/min (Strength of Recommendation C). 5. Acid-Base Disorders in CKD: Moderate metabolic acidosis (Bic 16-20) mEq/L is common with glomerular filtration rates below 20 ml/min, and favors bone demineralization due to the release of calcium and phosphate from the bone, chronic hyperventilation, and muscular weakness and atrophy. Its treatment consists of administration of sodium bicarbonate, usually orally (0.5-1 mEq/kg/day), with the goal of achieving a serum bicarbonate level of 22-24 mmol/L (Strength of Recommendation C). Limitation of daily protein intake to less than 1 g/kg/day is also useful (Strength of Recommendation C). Use of sevelamer as a phosphate binder aggravates metabolic acidosis since it favors endogenous acid production and therefore acidosis should be monitored and corrected if it occurs (Strength of Recommendation C). Hypocalcemia should always be corrected before metabolic acidosis in CKD (Strength of Recommendation B). Metabolic acidosis is an infrequent disorder and requires exogenous alkali administration (bicarbonate, phosphate binders) or vomiting.
...
PMID:[Electrolyte and acid-base balance disorders in advanced chronic kidney disease]. 1901 44
This review focuses on the cellular and molecular aspects underlying familial
neurohypophyseal
diabetes insipidus (DI), a rare disorder that is usually transmitted in an autosomal-dominant fashion. The disease, manifesting in infancy or early childhood and gradually progressing in severity, is caused by fully penetrant heterozygous mutations in the gene encoding prepro-
vasopressin-neurophysin II
, the precursor of the
antidiuretic hormone
arginine vasopressin (AVP). Post mortem studies in affected adults have shown cell degeneration in vasopressinergic hypothalamic nuclei. Studies in cells expressing pathogenic mutants and knock-in rodent models have shown that the mutant precursors are folding incompetent and fail to exit the endoplasmic reticulum (ER), as occurs normally with proteins that have entered the regulated secretory pathway. A portion of these mutants is eliminated via ER-associated degradation (ERAD) by proteasomes after retrotranslocation to the cytosol. Another portion forms large disulfide-linked fibrillar aggregates within the ER, in which wild-type precursor is trapped. Aggregation capacity is independently conferred by two domains of the prohormone, namely the AVP moiety and the C-terminal glycopeptide (copeptin). The same domains are also required for packaging into dense-core secretory granules and regulated secretion, suggesting a
disturbed balance
between the physiological self-aggregation at the trans-Golgi network and avoiding premature aggregate formation at the ER in the disease. The critical role of ERAD in maintaining physiological water balance has been underscored by experiments in mice expressing wild-type AVP but lacking critical components of the ERAD machinery. These animals also develop DI and show amyloid-like aggregates in the ER lumen. Thus, the capacity of the ERAD is exceeded in autosomal dominant DI, which can be viewed as a neurodegenerative disorder associated with the formation of amyloid ER aggregates. While DI symptoms develop prior to detectable cell death in transgenic DI mice, the eventual loss of vasopressinergic neurons is accompanied by autophagy, but the mechanism leading to cell degeneration in autosomal dominant
neurohypophyseal
DI still remains unknown.
...
PMID:Role of protein aggregation and degradation in autosomal dominant neurohypophyseal diabetes insipidus. 3266 12