Active clinical trials for "Diabetes Insipidus"

The differential diagnosis of central diabetes insipidus (cDI) is difficult and the current test with the highest diagnostic accuracy is copeptin measurement after hypertonic saline infusion (HIS). Although the HIS improved diagnostic accuracy compared to the standard water deprivation test used for decades before, it still comprises great discomfort for patients due to the rise in serum sodium levels above 149mmol/l and requires the presence of medical staff at all times to guarantee safety of the test. The arginine stimulation test is routinely used to stimulate growth hormone. Own data in 52 patients with polyuria / polydipsia syndrome showed that arginine infusion is a potent stimulator of the neurohypophysis and provides a new diagnostic tool in the differential diagnosis of cDI. Copeptin measurements upon arginine stimulation (CAS) discriminated patients with diabetes insipidus vs. patients with primary polydipsia with a high diagnostic accuracy of 94%. To validate these results and to compare them against the HIS a large multicenter trial is needed, where the diagnostic accuracy of the CAS is compared to the HIS.

This study aims to develop a method for the assessment of central NMDA receptor functioning in patients with depression and schizophrenia. For this purpose a transitional approach is used based on preclinical studies that show a dose-dependent relationship between the activity of hypothalamic NMDA receptor and plasma AVP response to increasing plasma osmolality. Patients with schizophrenia, depression and healthy controls participated in this study. The Investigators found that in a subgroup of patients with schizophrenia the AVP response was low and that in a subgroup of subjects with depression the AVP response was high compared to healthy controls.

Measurment of electrophysiological properties of the human pituitary gland during removal of a pituitary adenoma. Assessment if these properties are sufficient for intra-operative identification of different tissues.

This is a study to evaluate how the body handles and metabolizes (PK) the various doses of the drug Tolvaptan, and what the effect (PD) of the various doses of Tolvaptan are on the content of "salt" in blood and urine

The main interest of this study is to investigate the influence of moderate alcohol consumption (beer) on salt-water homeostasis. Therefore, 10 healthy volunteers will participate in 4 Intervention: Beer alone Beer and water Beer and salt (stock/bouillon) Water alone During the study day, copeptin, sodium, osmolality and urinary sodium/osmolality will be measured at 6 timepoints.

This study is to evaluate oxytocin levels in response to MDMA administration as compared to placebo in patients with diabetes insipidus and healthy volunteers.

Women are at greater risk for exercise-induced hyponatremia (low blood sodium concentration) and this risk has been attributed to their lower body weight and size, excess water ingestion and longer racing times relative to men. While these factors contribute to the greater incidence of hyponatremia in women, it is likely that their greater levels of estradiol in plasma and/or tissue also play a role in increasing the risk of hyponatremia in women. More importantly, estradiol may also leave women more susceptible to the extreme consequences of hyponatremia (i.e. brain damage, death). Hyponatremia is generally attributed to inappropriately elevated levels of the hormone arginine vasopressin (AVP). AVP is the most important hormone controlling water retention in the kidney. Earlier studies in our laboratory have demonstrated that estradiol lowers the threshold for thirst sensation and AVP release during exercise. The purpose of these studies is to test the hypotheses that in women with a history of hyponatremia, estradiol lowers the thresholds for thirst and AVP release, leading to greater fluid retention, lower blood sodium concentration during endurance exercise in the heat. However, we further hypothesize that progesterone administration along with estradiol administration will attenuate the effect of estradiol on the regulation of thirst and AVP, normalize fluid retention, and serum sodium concentration during endurance exercise in the heat. In women without a history of hyponatremia, we expect that estradiol administration will lower the thresholds for thirst and AVP release, but will not increase fluid retention or reduce blood sodium concentration during endurance exercise in the heat. We hypothesize that progesterone administration along with estradiol administration will attenuate the effect of estradiol on thirst and AVP, but have no effect on fluid retention or serum sodium concentration during endurance exercise in the heat. To test these hypotheses, women will perform endurance exercise in the heat under three hormonal conditions: 1) during Gonadotropin-releasing hormone (GnRH) antagonist alone--which will suppress estradiol and progesterone; 2) during GnRH antagonist+estradiol; and 3) during GnRH antagonist+estradiol+ progesterone. During exercise, fluid will be replaced with either water or a carbohydrate-electrolyte beverage (random assignment).

In this study, investigators aimed to investigate the effects of general and spinal anesthesia techniques on copeptin levels during cesarean section and their relation with fetal distress.

Background: - Oxytocin, a substance produced mostly in the brain, plays a role in influencing social interactions and reactions to stress, and may be related to pain. Arginine vasopressin, a hormone that regulates water, sugar, and salt in the blood, influences hostile behaviors and reactions to stress, and may also be related to pain. Researchers are interested in investigating both substances and their relationship to pain in healthy volunteers. Objectives: - To evaluate the effects of oxytocin and arginine vasopressin on pain in healthy volunteers. Eligibility: - Healthy volunteers between 18 and 55 years of age. Design: This study involves two 2-hour testing sessions held 1 day apart. Each session includes the administration of oxytocin, arginine vasopressin, or placebo (a nonactive substance), or no drug. The drugs and the placebo will be given by a nasal spray. At the first visit, participants will provide blood and saliva samples to measure hormone levels, and will be asked to fill out questionnaires about some psychological factors such as anxiety and empathy. Participants will then have an assessment of their sensitivity to pain, consisting of a brief electrical stimulation that lasts less than 1 second. After the pain assessment, participants will receive oxytocin, arginine vasopressin, placebo, or no drug at all, and will be monitored to provide baseline information. Participants will then have another pain sensitivity test and will complete the questionnaires again, and provide another saliva sample. At the second visit, participants will provide another saliva sample; receive oxytocin, arginine vasopressin, placebo, or no drug at all; and have tests of pain sensitivity and a pain-relieving procedure. During the pain-relieving procedure, participants will receive brief, moderately painful electrical shocks on the back of the nondominant hand and a low-level electrical stimulation on the middle finger that counteracts or reduces the pain from the shocks. Participants will rate their pain perception at the end of each stimulation by using a visual scale ranging from 0 (no pain) to 10 (maximum imaginable pain). The experiment ends with a final saliva collection and completion of the psychological questionnaires.

Patients being hospitalized for acute heart failure and already receiving standard therapy will be randomized to receive either tolvaptan or placebo, based on the level of copeptin measured in their bloodstream. Patients with high copeptin levels will be able to participate in the trial, patients with low levels will be excluded. Patients being admitted to the observation unit for acute heart failure and already receiving standard therapy will be randomized to receive either tolvaptan or placebo without consideration of the copeptin level. The hypothesis is that patients receiving tolvaptan will have better improvement of shortness of breath than those receiving placebo, within 9 hours of drug administration.