Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1332347 (ADH)
 2,230 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The stress response in humans commonly includes elevations in plasma concentrations of glucocorticoids, catecholamines, glucagon, growth hormone, aldosterone, and renin, resulting in alterations in the metabolism of glucose and other energy substrates, and in increased sodium and water retention. In severe illness, triiodothyronine and sometimes thyroxine are decreased without evidence of clinical hypothyroidism. Antidiuretic hormone may be elevated in bacterial meningitis and other central nervous system disorders, as well as in acute asthma, chronic ventilator therapy, pneumothorax, atelectasis, and postoperatively. Increased ADH concentration can lead to significant hypoosmolality and hyponatremia with adverse effects on the patient. In the setting of severe intracerebral insults, ADH may be inappropriately low, resulting in diabetes insipidus. Insulin concentrations may be inappropriately low for serum glucose concentration, or insulin may have diminished receptor responsiveness in seriously stressed patients. Either situation leads to hyperglycemia. Disturbances in calcium, phosphorus, and magnesium homeostasis may occur relatively frequently in the critically ill patient in response to therapeutic interventions, or illness-induced altered metabolism. It is not always clear when an altered metabolic or hormonal state is an appropriate response to a stress, or represents decompensation of the body's mechanisms for coping with that stress. It is important, however to recognize the common responses of the organism to severe illness, and to monitor for treatable abnormalities which occur.
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PMID:Endocrine manifestations of critical illness in the child. 354 20

Opioid peptides are found throughout the central nervous system, and have profound effects on neuroendocrine function. In man, exogenous opiates and opioids elevate circulating prolactin, GH and TSH, and suppress the release of the gonadotrophins and pro-opiocortin-related peptides. However, unlike in other species, there is substantial evidence for a physiological role of endogenous opioids only in the case of the gonadotrophins and ACTH/LPH. Most evidence suggests that LH and FSH are modulated via the hypothalamus or amygdala, where concentrations of opioids and opioid receptors are very high. Endogenous opioids appear to be principally concerned with the frequency-modulated release of GnRH, and this may be important clinically in patients presenting with amenorrhoea. ACTH/LPH are under tonic inhibition by endogenous opioids acting at hypothalamic and/or pituitary levels, and changes in this inhibition may be responsible for the release of these peptides in response to certain forms of stress. It has been reported that the opiate antagonist, naloxone, is clinically useful in paradoxically inhibiting the release of ACTH in patients with Nelson's syndrome, but this requires adequate confirmation. Vasopressin is under biphasic opiate control, but the principal effect is probably opiate-mediated inhibition of vasopressin release. The endogenous ligand for this response is likely to be dynorphin. Suppression of vasopressin release by opiates may become a useful therapy in the treatment of the 'Syndrome of inappropriate ADH'.
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PMID:Brain opiates and neuroendocrine function. 632 67

We studied factors that might be expected to influence Na+ absorption, the major active ion transport by excised rabbit trachea. Transepithelial electric potential difference (PD), short-circuit current (Isc), conductance (G), and unidirectional 22Na+ and 36Cl- flows were measured before and during exposure to a drug or after a change in bathing solution composition. Ouabain (3 X 10(-4) M) in the submucosal bath abolished Isc and Na+ absorption but increased G and unidirectional Cl- flows. Luminal amiloride (10(-3) M) abolished net Na+ absorption but reduced Isc by only 40%. Residual Isc was accounted for by induction of net Cl- secretion, which resulted from a reduction in mucosal (m)-to-submucosal (s) Cl- flux (J). Replacement of luminal Na+ by choline induced effects similar to those of amiloride. Residual Isc was not reduced by mucosal indomethacin (10(-6) M). Replacement of luminal Cl- by gluconate raised transepithelial PD fourfold, raised Isc 50%, decreased G 60%, and abolished net Na+ absorption by decreasing Jm leads to s and increasing Js leads to m. Luminal amphotericin B affected bioelectric properties and ion flows minimally, whereas monensin (10(-4) M) decreased Isc and net Na+ transport. Antidiuretic hormone (ADH, 1 U/ml) or aldosterone (10(-6) M) did not affect in Isc or PD after exposure up to 6 h. We conclude that 1) Na+ absorption across the rabbit trachea is ouabain sensitive, 2) the entry step for Na+ across the luminal membrane is amiloride sensitive, 3) Cl- secretion induced by amiloride or luminal Na+ replacement probably reflects a more favorable chemical gradient for basolateral coupled NaCl entry and/or electrical gradient for Cl- efflux across the luminal membrane, 4) the coupling of Na+ entry to the presence of Cl- in the mucosal solution is probably an electrical rather than a chemical cotransport process, and 5) the tracheal epithelium of the rabbit is not a target for aldosterone and ADH.
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PMID:Characteristics of sodium transport by excised rabbit trachea. 666 79

Eleven healthy subjects aged 18--26 years underwent intermittent heat stress in a sauna bath. Blood samples were taken immediately before, during and at various intervals after heat exposure for the measurement of antidiuretic hormone, osmolality and percentage change of plasma volume. Antidiuretic hormone was increased during, immediately after and 90 min after heat stress. Three hours after the heat stress period antidiuretic hormone returned to control values in spite of a significant increase in osmolality and a significant decrease in plasma volume. These results imply that other factors than ADH are responsible for the long-term homeostasis of water balance and plasma volume.
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PMID:Long-term observations on plasma antidiuretic hormone levels during and after heat stress. 720 27

The mechanisms by which elevated levels of vasopressin (ADH) in man and animals cause serious myocardial dysfunction, evidenced by arrhythmias, reduction in cardiac output and coronary blood flow, are not settled. Experiments were conducted in 16 isolated working left ventricles to examine their metabolic and hemodynamic responses to the infusion of vasopressin and the combination of vasopressin and epinephrine. Contractile performance was evaluated by analysis of positive dP/dt, contractile element velocities, and ventricular work-curves using stroke work/end-diastolic pressure. Relaxation parameters, including negative dP/dt and the early diastolic relaxation time constant, were also studied. Coronary blood flow was reduced 22% or less by vasopressin while cardiac output was maintained at a constant level. Myocardial oxygen consumption, lactate and potassium balances were determined from arterial and coronary sinus concentrations. Vasopressin produced myocardial dysfunction indicated by decrements in contractile and relaxation indices, without evidence of global ischemia. Epinephrine restored the mechanical performance to normal without significant change in coronary blood flow, myocardial oxygen consumption, or lactate and potassium balance.
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PMID:Mechanisms of impaired cardiac function by vasopressin. 736 15

Antidiuretic hormone (ADH; 2.5 x 10(-8) M vasotocin) produces a stimulation of apical fluid phase endocytosis, protein secretion and NaCl reabsorption in Xenopus laevis A6 distal nephron cell epithelia pretreated with aldosterone (10(-6) M). The increase of NaCl transport is mediated by a sequential opening of apical Cl and Na conductances. The aim of this study was to characterize the actin and tubulin cytoskeleton of A6 cells and to assess the impact of its disruption on baseline and ADH-induced apical vesicular membrane movements and ion transport to test for possible functional links. The microfilament (MF) and microtubule (MT) networks and their disruption were visualized by confocal laser microscopy. Conditions of depolimerization were selected, by cytochalasin D or cold and nocodazole, respectively. MF disruption produced an increase in baseline apical protein secretion (exocytic movements) (plus 18%) and a decrease of its induction by ADH (minus 35%). MF disruption also increased baseline horseradish peroxidase uptake (endocytic movements) (plus 21%), however, without affecting its ADH-induced increase. In the case of MT disruption, the ADH-induced stimulation of both protein secretion and fluid phase endocytosis was decreased by 70 and 44%, respectively. At the ion transport level, MF and MT disruption only insignificantly affected the ADH-induced Cl conductance, while they decreased the ADH-induced stimulation of Na transport (amiloride-sensitive short-circuit current and conductance) by a factor of 2 to 4. In conclusion, both MT and MF disruption decrease ADH-induced apical protein secretion and Na conductance, while the ADH-induced apical Cl conductance is not significantly affected. Taken together the data support the hypothesis that the modulation of Na channel expression by apical vesicular membrane movements plays a role in Na transport expression and its regulation by ADH.
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PMID:Cytoskeletal disruption in A6 kidney cells: impact on endo/exocytosis and NaCl transport regulation by antidiuretic hormone. 756 21

This investigation focuses on the hormonal response to electrolyte changes and water loss in patients suffering from heat exhaustion, hospitalized in Muna during Hajj seasons. The concentrations of cortisol, aldosterone, renin (PRA), vasopressin (ADH) parathyroid hormone (PTH), adrenocorticotrophic hormone (ACTH) and growth hormone (GH) were determined in venous blood samples drawn from the patients upon admission, during, and after treatment. Highly elevated PRA mean values (396.77 +/- 88.58-462.18 +/- 106.95 ng.ml-1.h-1) were recorded, with no statistically significant difference between the readings. A similar trend was seen for cortisol (42.92 +/- 4.30-60.20 +/- 11.90 ug/dl). Vasopressin (ADH) showed a highly elevated value upon admission (42.48 +/- 18.82 pg/ml), which decreased to 23.66 +/- 8.27 pg/ml during treatment, and declined further to 7.67, ranging between 4.04 and 11.30 pg/ml, thereafter. Statistically speaking, however, there was no significant difference between these readings. PTH concentration, on the other hand, increased from an initial value of 143.31 +/- 47.64 to 245.90 +/- 107.34 pmol/l after treatment, but again there was no significant difference between the values. ACTH concentrations showed no detectable values throughout this study. The GH concentration was within normal throughout, ranging from 4.42 +/- 0.87 to 5.19 +/- 1.78 ng/ml. Aldosterone concentration was significantly reduced in the patients upon admission, with an initial value of 187.93 +/- 21.41 pg/ml (p < 0.05 as compared to normal mean value). During and after treatment, aldosterone values were still significantly lower than normal mean (152.63 +/- 13.47, p < 0.05; 145.2 +/- 17.55, p < 0.01, respectively), thereby shedding some light on the possible etiology of persistent metabolic acidosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Physiological studies on heat exhaustion victims among Mecca pilgrims. 764 64

Chronic cervical spinal cord injury is characterized by defects in sodium and water homeostasis and defects of adaptive hormonal responses. The plasma osmolality is maintained in a relatively narrow range, the lower limit of which is determined by osmotic threshold for vasopressin release and the upper limit by the third threshold. Antidiuretic hormone as an important mediator of fluid and electrolyte balance was well investigated in able bodied children comparing children with normal voiding pattern and children with enuresis. The normal subjects were found to have higher plasma ADH at night, not detected in the group with enuresis. The findings were similar in elderly patients with increased diuresis at night, suggesting an important role of ADH in nocturnal decrease of urine output. Investigators studied the effect of rapid tilt on plasma ADH in tetraplegic compared with normal subjects, but there are no data available in the literature regarding ADH and its effects on water and electrolyte balance in healthy tetraplegic subjects with a normal lifestyle. We decided to undertake a pilot study to attempt to establish baseline ADH levels in this subject group, to better understand and manage tetraplegic patients with water and electrolyte dysregulation. Our preliminary data suggest that these individuals lack the normal diurnal variation of ADH, a phenomenon similar to that demonstrated in enuretic children and elderly, and furthermore appear to have generally depressed ADH levels.
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PMID:Antidiuretic hormone levels and polyuria in spinal cord injury. A preliminary report. 775 75

Vasopressin (ADH) increases transepithelial water flow in renal epithelia by a process that involves the insertion of water channels into the apical membrane. The objective of the present study was to examine membrane surface remodeling under conditions that promote the recovery of water channels. Hemibladders were set up as sacs with an imposed osmotic gradient. The control sacs received no hormone treatment, whereas the other sacs were stimulated with 100 mU/ml ADH for 10 or 15 min to induce exocytosis and enhanced water flow. ADH was then washed from the tissues with fresh buffer rinses to abolish the hormone actions. These tissues were then allowed to recover for 15, 30 and 60 min. During this time water channels are recovered intracellularly by a process of endocytosis. This time period was called the retrieval period. At specified time intervals, tissues were fixed and processed for SEM or embedded in epon for ultrathin sectioning for TEM studies. Control tissues, regardless of the length of time, showed little or no sign of surface remodeling that was indicative of endocytosis during pre- or post-buffer washes, whereas the ADH-treated tissues showed a time-dependent remodeling of the apical membrane during activation and following removal of the hormone during the retrieval period. At the 10 min retrieval period, greater than 47% of the granular cells showed extensive surface remodeling. By 30 and 60 min posthormone treatment during recovery, fewer than 23% of granular cells showed signs of surface membrane changes. During retrieval the apical membrane undergoes a transition with a loss of both microridges and microvilli prior to membrane restoration. These observations suggest that apical membrane remodeling is crucial for the restoration of membrane permeability following hormone activation and termination.
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PMID:Surface membrane remodeling following removal of vasopressin in toad urinary bladder. 802 24

Hyponatremia is the most frequent electrolyte disorder. Two forms of it, the "true"--and "pseudo"--hyponatremia are known. The normal osmoregulation is an accurate operation which ensures the steadiness of serum sodium level by regulating vasopressin (ADH) release and water intake. Hyponatremia usually indicates water excess in the body, however, it may be complicated by sodium loss as well. It has hypovolemic, hypervolemic and normovolemic forms; the syndrome of inappropriate antidiuretic hormone (SIADH) is associated mostly with the normovolemic states. Nowadays the pathomechanism, criteria, diagnosis and etiologic factors of SIADH (water intoxication) are fairly well known, but the number of drugs capable of inducing this syndrome is increasing day by day. According to the newest knowledge, SIADH may exist not only in the acute but chronic form as well, which should be born in mind when treating water intoxicated patients. The basic principle is that in cases with mild clinical disturbances aggressive treatment should be avoided. For mild hyponatremia water restriction is usually sufficient, but in serious cases hypertonic saline infusion should be administered. Its speed has to be determined and adjusted carefully according to the needs of the patient, and it can be combined with the administration of furosemide, when necessary. Vasopressin antagonists are under clinical investigation, their therapeutic value has not yet been determined. Water intoxication is not rare-if one keeps it in mind. The syndrome's simple treatment can be life saving for the patient and provides an easy problem solution for the physician.
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PMID:[Hyponatremia]. 943 52


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