Search results for "Pituitary"

Release of endogenous 3,4-dihydroxyphenylethylamine and its metabolites from the isolated neurointermediate lobe of the rat pituitary gland. Effects …

1986

: Isolated rat neurointermediate lobes were incubated in vitro. The release of 3,4-dihydroxyphenylethylamine (dopamine, DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and methoxyphenylethanol (MOPET) was determined by HPLC with electrochemical detection. Under resting conditions, the outflow of metabolites was 35–50 times that of DA. HVA accounted for 50%, DOPAC for 45%, and MOPET for 5% of the metabolites. Although an equivalent of 40–50% of the tissue DA content was released per hour as metabolites, the tissue DA content was not reduced after 110 min of incubation. The spontaneous outflow of DA and its metabolites was not affected by the DA uptake inhibitor GBR 12921 (1…

Isoprenaline and forskolin increase evoked vasopressin release from rat pituitary

1982

Isolated neurointermediate lobes of rat pituitaries were incubated in Krebs solution. The vasopressin release evoked by electrical stimulation (0.2 ms, 80 V, 15 Hz, 10 s trains at 10 s intervals for a total of 10 min) was completely inhibited by tetrodotoxin. Isoprenaline increased the evoked vasopressin release to a maximum of 60% (EC50 10 nM) and this effect was antagonized surmountably by propranolol. Forskolin increased the vasopressin release by 98%. These results suggest the presence within the neurohypophysis of a beta-adrenoceptor-linked adenylate cyclase facilitating vasopressin secretion.

Computed Tomography in Brain Tumors

1981

Craniocerebral injury and brain tumor are the two most important indications for CT studies. There is unanimous agreement that computed tomography is unequalled in its diagnostic accuracy in demonstration of intracranial tumors. Our own experience is based on observations in 3,750 patients with brain tumors or cerebral metastases who were studied in the period from December 1974 to March 1980 (Table 1). Initial CT studies demonstrated the intracranial tumor or tumors in 3,589 cases (95.7%). Several CT examinations were necessary for diagnosis of a brain tumor in 112 patients (3.0%). Other diagnostic procedures or postmortem studies revealed a brain tumor which had not been demonstrated with…

Dopaminergic modulation of evoked vasopressin release from the isolated neurohypophysis of the rat

1982

1. Neurointermediate lobes of rat pituitaries were incubated in Locke or Krebs solution, and the vasopressin released into the medium was assayed on the blood pressure of the pithed rat or by a radioimmunological procedure. Release of vasopressin over resting levels was evoked either by incubation with 60 mM KCl (high K) solution or by electrical stimulation of the pituitary stalk. Two different kinds of electrical stimulation were carried out. Procedure A (1 ms, 10 Hz, 5 times for 1 min within 10 min) induced a vasopressin overflow which was greatly calcium-dependent but only insignificantly sensitive to tetrodotoxin (TTX). Procedure B (0.2 ms, 15 Hz, 10 s trains with 10 s intervals for 10…

Differential effects of potassium channel blockers on neurohypophysial release of oxytocin and vasopressin. Evidence for frequency-dependent interact…

1988

Isolated rat neurohypophyses were fixed by their stalks to a platinum wire electrode and superfused with Krebs-HEPES solution. Vasopressin and oxytocin released into the medium were determined by specific radioimmunoassays. Hormone secretion was increased by electrical stimulation of the pituitary stalk at different frequencies. The effects of several potassium channel blockers, tetraethylammonium (TEA) ions, 4-aminopyridine (4-AP) and 3,4-diaminopyridine (3,4-DAP) were tested. The release of vasopressin and oxytocin evoked by electrical stimulation with 900 pulses at 15 Hz (about 900 and 1,000 μU, respectively) was about 10 times higher than that evoked by 900 pulses at 3 Hz. Both 10 and 3…

Complete biochemical control and pituitary adenoma disappearance in a child with gigantism: Efficacy of octreotide therapy

2011

Hypothalamic-Pituitary-Adrenal axis and cognitive function in healthy older people: genetic, situational and individual factors

2019

The world population is getting older, and this age group faces important health challenges, among which age-related cognitive decline stands out. Therefore, it is important to identify vulnerability and protective health factors in order to understand ways to prevent cognitive decline. This thesis aimed to address the relationship between the Hypothalamic–Pituitary–Adrenal (HPA) axis and cognitive functioning during aging, taking into account genetic (Apolipoprotein E, ApoE, polymorphism), situational (loneliness), and individual factors (personality traits). To do this, a group of healthy older people over 55 years of age, men and women, were evaluated. A neuropsychological battery was ad…

Loneliness in adult people: its relationships with stress, health and hypothalamic-pituitary-adrenal axis functioning

2022

El sentiment de solitud és un dels principals problemes de les societats occidentals. En els últims anys els avanços en internet ens han portat a ser una societat més connectada que mai, a pesar d’açò, aquest sentiment s’està incrementant. Per sobreviure i prosperar, els éssers humans necessitem dels altres per satisfer les necessitats d’afecte, pertinença i reconeixement. D’aquesta manera, la solitud sorgeix de la discrepància entre les relacions íntimes i socials desitjades i les reals. La investigació indica que la solitud està relacionada amb l’estrès i amb diverses conseqüències en la salut tant física com psicològica. Aquesta es pot experimentar al llarg de la vida, encara que és més …