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

Small elevations in corticosterone (B) administered exogenously exert potent inhibitory effects on both basal and stress-induced ACTH secretion. However, under conditions of chronic stress with chronic elevations in B, the hypothalamo-pituitary-adrenal system appears to balance the negative feedback signal of B with central neural facilitation so that the system remains fully responsive to acute stressors. In these studies, we tested whether: 1) circulating B concentrations affect responses to acute restraint in rats exposed to 5 days at 5-7 C (cold), compared with room temperature (control); and 2) facilitated ACTH secretion can be explained by increased CRF or vasopressin messenger RNA (mRNA) levels in the hypothalamic parvocellular paraventricular nuclei (PVN). Rats were adrenalectomized and supplied with B in doses that fixed plasma B at constant levels between approximately 2 and 20 microg/dl; rats were placed in cold or remained as controls. Increasing concentrations of fixed B decreased basal ACTH similarly in both groups. By contrast, as B levels increased, ACTH responses to restraint also increased in cold vs. control rats. Semiquantitative analysis of CRF mRNA by in situ hybridization revealed decreases of similar magnitude in both groups with increasing fixed B. Vasopressin mRNA levels also decreased with increasing fixed B in both groups, but with slightly less sensitivity to inhibition by B in cold exposed rats. Taken together, the decreases in mRNA for these major ACTH neuropeptide secretogogues in the parvocellular PVN are unlikely to explain facilitated ACTH responses in chronically stressed rats. We conclude that a brain site is stimulated by B that is proximal to the PVN; feedforward, positive effects of B are thus implicated in mediation of prior stress-induced facilitation of acute hypothalamo-pituitary-adrenal responses to stress.
 ...
PMID:Chronic cold in adrenalectomized, corticosterone (B)-treated rats: facilitated corticotropin responses to acute restraint emerge as B increases. 923 75

Lewis rats display hyporesponsive hypothalamo-pituitary-adrenocortical (HPA) axes, overproduction of cytokines, and susceptibility to inflammatory disease. The Lewis corticotropin-releasing hormone (CRH) neurosecretory system contains normal numbers of vasopressin (VP)-deficient axon varicosities, but abnormally sparse VP-containing varicosities in the external zone of the median eminence, compared to the normoresponsive Sprague Dawley (SD), Wistar and Fischer 344 strains. Since VP may act as a thyrotropin-releasing factor, we hypothesized that thyroid axis responsivity may be altered in Lewis rats. T3, T4 and TSH were measured by radioimmunoassay, and free T4 by equilibrium dialysis, in adult male Lewis and SD rats. One h cold (5 degrees C) induced significant increases in T3, T4 and TSH levels in Lewis rats but not in SD rats. Ninety min insulin-induced hypoglycemia (1 IU/kg, i.p.) induced a significant T3 increase in Lewis rats and a significant T4 increase in SD rats. Two h after ip LPS (0.25 or 0.75 mg/kg), T4 levels fell significantly in Lewis rats but not in SD rats. TSH decreases were significant in Lewis rats after 0.75 mg/kg and in SD rats after 0.25 mg/kg. Baseline hormone levels were generally higher in Lewis rats; the differences were significant for T3 and T4 in the insulin experiments and for T3, T4 and free T4 in the LPS experiments. The data suggest that reduced inhibition from the adrenocortical axis in Lewis rats leads to hyperresponsivity of the thyroid axis to cold, and greater LPS-induced decreases in T4 levels, probably due to an exaggerated inhibitory cytokine response.
 ...
PMID:Altered thyroid axis function in Lewis rats with genetically defective hypothalamic CRH/VP neurosecretory cells. 943 Aug 24

Cold preservation of kidneys is commonly used in human transplantation and in vitro studies. However, although disruption of the cytoskeleton by cold has been demonstrated in cultured cells, the effect of cold treatment on intact kidney is poorly understood. In this study, specific antibodies were used to examine the effect of hypothermia on the cytoskeletal network and the trafficking of some membrane proteins in the urinary tubule. Rat kidneys were cut into thin slices (approximately 0.5 mm) that were divided into several groups: (1) some were immediately fixed in paraformaldehyde, sodium periodate, and lysine (PLP); (2) some were stored at 4 degrees C for 15 min or 4 h before being fixed in cold PLP; or (3) after 4 h cold treatment, some slices were rewarmed to 37 degrees C for 15, 30, and 60 min in a physiologic solution, pH 7.4, and were then fixed in warm PLP. Immunofluorescence staining revealed an almost complete disruption of the microtubule network in proximal tubules after 15 min cold treatment, whereas microtubules in other segments were affected after 4 h. A partial recovery of the microtubule network was observed after 60 min rewarming. In contrast, actin filaments seemed to be resistant to cold treatment. gp330, aquaporin-2, H+ ATPase, and the AE1 anion exchanger were all relocated into numerous vesicles that were distributed throughout the cytoplasm after hypothermia followed by rewarming, whereas Na-K-ATPase retained its basolateral localization. The vasopressin-stimulated insertion of aquaporin-2 water channels into the apical membrane was inhibited during the initial rewarming period after cold exposure. Thus, cold preservation of tissues might impair, at least transiently, the polarized membrane expression and function of some transport proteins in renal epithelial cells.
 ...
PMID:Cold-induced microtubule disruption and relocalization of membrane proteins in kidney epithelial cells. 952 91

Pretreatment and removal of vasopressin (ADH) in toad urinary bladder renal model tissues induces endocytosis at 25 degrees C. The objective of the current study is to determine if apical membrane remodeling, as well as transepithelial water flow, can be affected by lowering the temperature to 15 degrees C. Control toad urinary bladders in the presence of an osmotic gradient at either 25 degrees C or 15 degrees C when visualized by scanning electron microscopy (SEM) show a typical apical membrane surface with no apparent surface differences. ADH-treated tissues following 15-min stimulation at 25 degrees C or 15 degrees C revealed a propagation of apical microvilli on their surface membranes. After 15 min following removal of ADH, bladder tissues at 25 degrees C or 15 degrees C showed surface invaginations involving over 44% and 80% of granular cells, respectively. The rate of water flow in tissues at 15 degrees C remained elevated compared to tissues held at 25 degrees C. This was consistent with the observation that ADH-stimulated tissues following washout at 15 degrees C still had marked apical membrane surface involvement. However, at 30 min and 60 min postwashout, ADH-stimulated tissues at 15 degrees C recovered considerably, with a reduction in the number of shallow apical membrane invaginations involving fewer than 33% and 20% of granular cells respectively. This may indicate that the membrane undergoes continuous remodeling even at cold temperature conditions but with a different half-time. Control bladder tissues subjected to transmission electron microscopy (TEM) reveal a dense cytoplasmic profile with a scattered distribution of secretory granules, rough ER cisternae, mitochondria, and little or no vacuolation. In contrast, ADH-stimulated bladder tissues displayed a vacuolated cytoplasm, expanded rough ER cisternae, and ruffled basolateral membranes. These observations suggest that the apical membrane undergoes considerable reorganization following cessation of hormone action and that lowering the temperature reduces the rate of membrane remodeling and thus may provide a means to monitor the processes of endocytosis and the mechanisms responsible for water channel retrieval.
 ...
PMID:Effect of temperature on apical membrane remodeling in ADH-stimulated toad urinary bladders. 971 73

Vasopressin, released from the posterior pituitary and from the vascular endothelium, can cause vasoconstriction and provoke platelet aggregation, leading to an impaired tissue blood supply. In humans with pituitary diabetes insipidus the central release of vasopressin is diminished, and in the Brattleboro homozygous rat there is congenitally no synthesis of this hormone. The gastroduodenal intramucosal vasopressin level is elevated in normal rats following various acute ulcerogenic challenges (after ethanol, reserpine, indomethacin, cold-restraint stress, endotoxin shock and hemorrhagic shock), and vasopressin-deficient rats are less sensitive to these stimuli. In a hospital- and population-based case-control, age-matched retrospective study, the incidence of human gastroduodenal ulceration is significantly higher in the normal population (in whom the release of vasopressin is presumed to be intact) than in the vasopressin-deficient one (central diabetes insipidus patients). In conclusion, endogenous vasopressin plays an aggressive role in development of gastroduodenal ulceration, especially that related to stress.
 ...
PMID:Deleterious action of vasopressin in gastroduodenal ulceration: experimental and clinical observations. 986 15

Animals prenatally exposed to ethanol typically exhibit hypothalamic-pituitary-adrenal (HPA) hyperresponsiveness to stressors. In contrast to previous studies that have investigated effects of prenatal ethanol exposure on HPA responses to acute or intermittent stressors, our study investigated HPA responses to a chronic continuous stressor, cold stress (4 degrees C for 0, 1, or 3 days). We tested the hypothesis that prenatal ethanol exposure would result in increased plasma corticosterone (CORT) and adrenocorticotropin (ACTH) responses and increased peptide [corticotropin-releasing factor and vasopressin] mRNA levels in the paraventricular nucleus (PVN) of the hypothalamus compared to that in control animals. In addition, CORT and ACTH responses were measured after exposure to an acute stressor (i.p. isotonic saline injection), superimposed during chronic cold exposure, to examine possible sensitization of the HPA response to the acute stress. Thus, blood samples were collected at the end of each of the three periods of cold exposure, either before (0 min) or 15 min after acute stress. The subjects were adult male and female Sprague-Dawley rat offspring from prenatal ethanol (E), pair-fed (PF), and ad libitum-fed control (C) treatment groups. Exposure to cold stress resulted in significant body weight loss in E males at 1 day and in both males and females of all prenatal treatment groups by 3 days of cold stress. Males in all prenatal groups also exhibited significant increases in adrenal weight:body weight ratios. Cold stress alone (0 min condition) increased CORT levels in E males and overall ACTH levels in E males and females compared to controls. ACTH levels were also higher overall in E compared to control males after acute stress (15 min condition). Sensitization of the CORT response to acute stress was observed in males but not females across all prenatal treatment groups. Corticotropin-releasing factor and vasopressin mRNA levels in the PVN were not significantly affected by prenatal treatment or chronic cold stress in either males or females. In contrast, both males and females displayed increases in PVN thyrotropin-releasing hormone (TRH) mRNA levels after cold stress. These data support and extend previous work demonstrating differential effects of prenatal ethanol exposure on HPA responsiveness of male and female offspring, and suggest that E males may be more vulnerable to the effects of chronic cold stress than E females.
 ...
PMID:Effects of prenatal ethanol exposure on hypothalamic-pituitary-adrenal responses to chronic cold stress in rats. 1006 60

In this pilot study, 6 patients who complained of persisting coldness after brain injury were treated with intranasal vasopressin (DDAVP) twice daily for 1 month. Response was assessed after 1 month of treatment, DDAVP was discontinued, and response was reassessed 1 month later. Five of the 6 patients had a dramatic response to DDAVP, as soon as 1 week after initiating treatment, and no longer complained of feeling cold. Response persisted even after discontinuation of treatment. Patients denied any side effects from treatment with DDAVP. The experience of persisting coldness can respond dramatically to brief treatment with intranasal DDAVP. The authors discuss possible mechanisms of action to explain this phenomenon.
 ...
PMID:Vasopressin treats the persistent feeling of coldness after brain injury. 1033 96

Motion sickness provides a unique setting for the study of nausea. Studies of illusory self-motion have linked nausea and objective measures of gastric dysrhythmias and the stress hormones vasopressin and epinephrine. Electrogastrographic methods utilize Ag-AgCl electrodes placed on the abdominal surface in the epigastric region to record electrogastrograms (EGGs), a noninvasive measure of gastric myoelectrical activity. The EGG frequencies of interest are the normal range (2.4-3.6 cpm), tachygastrias (3.6-9.9 cpm), and bradygastrias (1.0-2.4 cpm), and duodenal respiratory frequencies (10.0-15.0 cpm). Illusory self-motion or vection is produced with a rotating drum. Minutes before vection-induced nausea is reported, the baseline EGG signal shifts into tachygastrias or mixed tachygastrias and bradygastrias. Quantitative analyses show that the percentage of power in the tachygastria range correlates with the intensity of nausea. Plasma vasopressin levels correlate positively with intensity of nausea. Asian subjects have higher intensity nausea and higher vasopressin levels compared with Caucasian subjects, indicating a potential genetic susceptibility to vection-induced motion sickness and nausea. Vection-induced motion sickness represents an experimental model of acute-onset nausea with accompanying symptoms such as headache, drowsiness, cold sweating, and fatigue. Illusory self-motion is a purely central nervous system (visual-vestibular) stimulation that evokes dramatic shifts in gastric electrical activity and significant release of the posterior pituitary hormone vasopressin. Central nervous systems pathways that evoke gastric dysrhythmias and release vasopressin may also have a pathophysiologic role in the cyclic vomiting syndrome.
 ...
PMID:Illusory self-motion and motion sickness: a model for brain-gut interactions and nausea. 1049 40

Distinct brain peptidergic circuits govern peripheral energy homeostasis and related behavior. Here we report that mitochondrial uncoupling protein 2 (UCP2) is expressed discretely in neurons involved in homeostatic regulation. UCP2 protein was associated with the mitochondria of neurons, predominantly in axons and axon terminals. UCP2-producing neurons were found to be the targets of peripheral hormones, including leptin and gonadal steroids, and the presence of UCP2 protein in axonal processes predicted increased local brain mitochondrial uncoupling activity and heat production. In the hypothalamus, perikarya producing corticotropin-releasing factor, vasopressin, oxytocin, and neuropeptide Y also expressed UCP2. Furthermore, axon terminals containing UCP2 innervated diverse hypothalamic neuronal populations. These cells included those producing orexin, melanin-concentrating hormone, and luteinizing hormone-releasing hormone. When c-fos-expressing cells were analyzed in the basal brain after either fasting or cold exposure, it was found that all activated neurons received a robust UCP2 input on their perikarya and proximal dendrites. Thus, our data suggest the novel concept that heat produced by axonal UCP2 modulates neurotransmission in homeostatic centers, thereby coordinating the activity of those brain circuits that regulate daily energy balance and related autonomic and endocrine processes.
 ...
PMID:Brain uncoupling protein 2: uncoupled neuronal mitochondria predict thermal synapses in homeostatic centers. 1057 39

The causes of pituitary apoplexy are unclear. We report a case of pituitary apoplexy presenting with headache and nausea. On June 17th, 1997 a 74-year-old woman had complained of retro-orbital headache, fever and vomiting. A cold was diagnosed for which she recurred medication. In addition to the previous symptoms she was getting to lose appetite. She was admitted to our hospital for further examination and treatment on June 21. On admission neurological examination showed left pupil mydriasis, the left eye had no light reflex and the right eye had only a slight response to the light. She could hardly move both eyeballs up. Laboratory data showed a normal white blood cell count and the CRP was 16.2 mg/dl. Lumbar puncture showed 97 mg/dl total protein and 82 cells per microliter, most of which were lymphocytes. We diagnosed viral infection based on the evidence of clinical symptoms and lumbar puncture data. The patient was treated with gamma-globulin and improved. From the 16th day of sickness we recognized symptoms of oculomotor paralysis and the syndrome of inappropriate antidiuretic hormone. On the 23rd day of sickness we strongly suspected pituitary apoplexy based on transaxial MR images. After absorption of intra-tumor hemorrhage, the oculomotor symptoms recurred. We finally reached a diagnosis of pituitary apoplexy based on pathological material, MR images, symptoms and laboratory data. We must think of pituitary apoplexy when we see an aged out-patient with severe headache, nausea, vomiting and oculomotor paralysis. It was difficult to diagnose this disease in the early time course of the disease.
 ...
PMID:[A case of pituitary apoplexy approving as severe headache and nausea]. 1065 40


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>