Search results for " vasopressin"

Oxytocin and vasopressin expression in the turbinates of patients with chronic sinusitis

2013

Many peptides are present in the nasal mucosa, but few studies have investigated the presence or absence of the oxytocin and vasopressin peptides. This immunohistochemical study on the inferior turbinates of patients affected by chronic sinusitis shows, for the first time, that these peptides are present in the epithelium of both nasal mucosa and glands. Their presence could be related to the presence of atrial natriuretic peptide (ANP), like previously demonstrated in other organs such as heart and prostate, since in some circumstances they play in antagonism.

Agonist and antagonist-dependent internalization of the human vasopressin V2 receptor.

1998

Abstract In this report we demonstrate that in HEK293 cells stably expressing the human V2vasopressin receptor, ligand-induced internalization of the hormone receptor occurs via the clathrin-dependent pathway. Studies of receptor trafficking either by direct visualization of the V2receptor by confocal microscopy or binding experiments show a rapid internalization (half-time 6–7 min). Blocking of the clathrin-dependent pathway by hypertonic sucrose increased vasopressin-induced cellular cAMP production and decreased the desensitization of the V2receptor–adenylyl cyclase system. Thus, internalization appears to be a major regulatory mechanism terminating vasopressin action in HEK293 cells. Tw…

Effects of tetraethylammonium ions on frequency-dependent vasopressin release from the rat neurohypophysis.

1988

1. Isolated rat neurohypophyses were fixed by their stalks to a platinum wire electrode and superfused with oxygenated Krebs-HEPES solution. Vasopressin release into the medium was determined by radioimmunoassay. Vasopressin secretion was increased by electrical stimulation at different frequencies (3-30 Hz) and different train lengths (75-900 pulses). The effects of tetraethylammonium (TEA) ions and of enhanced calcium were tested. 2. Electrical stimulation at 7.5 or 15 Hz evoked a markedly larger release of vasopressin than stimulation at 3 Hz. During continuous stimulation at 7.5 and 15 Hz the evoked vasopressin release per pulse declined rapidly, but with similar time constants for both…

Arginine Vasopressin Enhances Sympathetic Constriction Through the V1 Vasopressin Receptor in Human Saphenous Vein

1998

Background—Arginine vasopressin (AVP) not only acts directly on blood vessels through V1 receptor stimulation but also may modulate adrenergic-mediated responses in animal experiments in vivo and in vitro. The aim of the present study was to investigate whether AVP can contribute to an abnormal adrenergic constrictor response of human saphenous veins. Methods and Results—Saphenous vein rings were obtained from 32 patients undergoing coronary artery bypass surgery. The vein rings were suspended in organ bath chambers for isometric recording of tension. AVP (331029 mol/L) enhanced the contractions elicited by electrical field stimulation at 1, 2, and 4 Hz (by 80%, 70%, and 60%, respectively) …

Circadian variations of ?synaptic? bodies in the pineal glands of Brattleboro rats

1990

The function of the mammalian pineal gland is regulated primarily by the sympathetic system. Arginine-vasopressin (AVP) may also be involved in the regulation of pineal melatonin synthesis under experimental conditions. The present study was conducted in the AVP-deficient rat strain, the Brattleboro rat, to investigate whether the numbers and rhythms of pineal "synaptic" bodies in this strain are different from those found in intact rats. AVP or its non-vasoconstrictive analog, deamino-D-AVP, was also injected intra-arterially in Brattleboro or Sprague-Dawley rats to test whether this procedure influences "synaptic" body numbers. Brattleboro rats were killed at different time-points through…

Bases hormonals de la conducta prosocial: una revisió de la literatura

2016

Resumen: En los últimos años se ha intensificado el estudio de las conductas prosociales, incluyendo una mayor atención a los aspectos neuropsicobiológicos implicados en tales conductas, para entender su funcionamiento, así como para fomentarlas. Las investigaciones también pueden proporcionar una aproximación a la búsqueda de tratamientos más acertados a aquellas enfermedades en las que la cognición social se ve alterada. El objetivo principal del presente trabajo es establecer el estado actual de la cuestión, revisando la literatura publicada sobre las hormonas que influyen a la conducta prosocial, tanto en animales como en humanos. Los resultados de la investigación apuntan a la oxitocin…

2015

Several point mutations have been identified in human aquaporins, but their effects on the function of the respective aquaporins are mostly enigmatic. We analyzed the impact of the aquaporin 2 mutation V71M, which causes nephrogenic diabetes insipidus in humans, on aquaporin structure and activity, using the bacterial aquaglyceroporin GlpF as a model. Importantly, the sequence and structure around the V71M mutation is highly conserved between aquaporin 2 and GlpF. The V71M mutation neither impairs substrate flux nor oligomerization of the aquaglyceroporin. Therefore, the human aquaporin 2 mutant V71M is most likely active, but cellular trafficking is probably impaired.

The AQP2 mutation V71M causesnephrogenic diabetes insipidus in humans but does not impair the function of a bacterial homolog

2015

Graphical abstract