Search results for "Clamp"
showing 10 items of 243 documents
Cl−uptake promoting depolarizing GABA actions in immature rat neocortical neurones is mediated by NKCC1
2004
GABA is the principal inhibitory neurotransmitter in the mature brain, but during early postnatal development the elevated [Cl−]i in immature neocortical neurones causes GABAA receptor activation to be depolarizing. The molecular mechanisms underlying this intracellular Cl− accumulation remain controversial. Therefore, the GABA reversal potential (EGABA) or [Cl−]i in early postnatal rat neocortical neurones was measured by the gramicidin-perforated patch-clamp method, and the relative expression levels of the cation−Cl− cotransporter mRNAs (in the same cells) were examined by semiquantitative single-cell multiplex RT-PCR to look for statistical correlations with [Cl−]i. The mRNA expression …
IRS-2 deficiency impairs NMDA receptor-dependent long-term potentiation
2011
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License.-- et al.
Proton conductance of human transient receptor potential-vanilloid type-1 expressed in oocytes of Xenopus laevis and in Chinese hamster ovary cells.
2004
Transient receptor potential-vanilloid type-1 (TRPV1) is a ligand-gated cation channel with preference for divalent cations, especially Ca(2+) (sequence of conductances: Ca(2+)Mg(2+)Na(+) approximately/= K(+) approximately/= Cs(+)). In the present study, the two-electrode voltage-clamp technique was used on oocytes of Xenopus laevis expressing TRPV1 to evaluate whether human TRPV1 also conducts protons. In medium devoid of K(+), Na(+), Mg(2+), and Ca(2+), capsaicin 1 microM induced a significant inward current (62% of the current in physiological medium). The effects of capsaicin were abolished in the presence of capsazepine 3 microM. The capsaicin-induced currents in medium devoid of Na(+)…
Allosteric sensitization of nicotinic receptors by galantamine, a new treatment strategy for Alzheimer’s disease
2001
Cholinesterase inhibitors are the only approved drug treatment for patients with mild to moderately severe Alzheimer's disease. Interestingly, the clinical potency of these drugs does not correlate well with their activity as cholinesterase inhibitors, nor is their action as short lived as would be expected from purely symptomatic treatment. A few cholinesterase inhibitors, including galantamine, produce beneficial effects even after drug treatment has been terminated. These effects assume modes of action other than mere esterase inhibition and are capable of inducing systemic changes. We have recently discovered a mechanism that could account, at least in part, for the above-mentioned unex…
Oxygen and glucose deprivation induces major dysfunction in the somatosensory cortex of the newborn rat
2005
The mechanisms and functional consequences of ischemia-induced injury during perinatal development are poorly understood. Subplate neurons (SPn) play a central role in early cortical development and a pathophysiological impairment of these neurons may have long-term detrimental effects on cortical function. The acute and long-term consequences of combined oxygen and glucose deprivation (OGD) were investigated in SPn and compared with OGD-induced dysfunction of immature layer V pyramidal cortical neurons (PCn) in somatosensory cortical slices from postnatal day (P)0-4 rats. OGD for 50 min followed by a 10-24-h period of normal oxygenation and glucose supply in vitro or in culture led to pron…
MODIFICATION OF COAGULATION IMBALANCE DURING ANTITHROMBIN TREATMENT IN PREECLAMPTIC PATIENTS: OUR EXPERIENCE
2008
Preeclamptic conditions are often associated with a natural inhibitor consumption. Many studies have evidenced validity of antithrombin (AT) treatment during preeclamptic conditions. The aim of the study is to restore a congruous coagulation imbalance with administration of AT under the guide of thromboelastographic monitoring (TEG).
Vergleich des Hypoglykämieempfindens und der hormonellen Gegenregulation während einer kontrollierten Hypoglykämie: Ein Beitrag zur Diagnostik des Hy…
2008
BACKGROUND AND OBJECTIVE Diabetics with abnormal hypoglycaemia awareness cannot recognize hypoglycaemic symptoms early and adequately enough to respond, thus endangering in everyday life not only themselves but also others. Thus it is important to diagnose such symptoms early and assess the extent to which the diabetic is at risk of severe hypoglycaemia. This study was designed to contribute to the evaluation of hypoglycaemia awareness in type 1 (IDDM) diabetics. PATIENTS AND METHODS In 57 diabetics (IDDM) awareness of typical hypoglycaemic warning symptoms and of hormonal counterregulation were tested during controlled induced hypoglycaemia. A questionnaire was used to measure at fixed tim…
Morphology of placental villi after premature delivery and its clinical relevance
1986
Based on a new concept of maturation of the placental villous tree and its disorders (synchronous and asynchronous immaturity, asynchronous maturity, hyperpermaturity, and terminal villi deficiency) we studied the possible effect of the placental villous tree on the premature onset of labour. In mature normal neonates irregular and asynchronous villous patterns were found in 50% of cases. In prematurely delivered neonates, only 33% of the corresponding placentas show synchronous immature villous patterns. Uterine bleeding in the first trimester was associated with a 42% of incidence of premature maturation of the villous tree. These findings strengthen the idea that hormonal imbalance in ea…
67 The effect of hypertensive disorders of pregnancy on the risk of attention-deficit/hyperactivity disorder in the offspring
2016
Introduction Attention-deficit/hyperactivity disorder (ADHD) is a frequent neurodevelopmental disorder. Inadequate placentation as a result of hypertensive disorders of pregnancy has been proposed to be a central mechanism of fetal neurodevelopmental comprise. Recently it has been shown that pre-eclampsia increases the risk of ADHD [Mann and McDermott, 2011] . Objectives We examined the association between hypertensive disorders of pregnancy and ADHD and behavioural difficulties among 7-year old children. We also examined whether circulating factors in serum from women with a HDP alter early patterns of fetal neural growth. Methods The study cohort consisted of 13,192 children (weighted = 1…
Artrial Natriuretic Peptide Concentrations in Preeclampsia
1989
During pregnancy various humoral and functional mechanisms were recognized, that regulate the water and electrolyte household. In preeclampsia, increased water-sodium retention results from a variety of pathophysiological changes in the endocrinological system. There are also organ-specific changes, such as renal clearance reduction up to 30% in comparison to normal pregnancy. For many years, physiologists expected to find additional cardial mechanisms that influence homeostasis. In 1981, de Bold [3] identified ANP a new humoral factor that leads to increased water and sodium excretion. The influence of ANP in preeclampsia has been the subject of controversial discussion.