Search results for "Atropine"

Altered gastrointestinal motility in an animal model of Lesch-Nyhan disease.

2018

Mutations in the HGPRT1 gene, which encodes hypoxanthine-guanine phosphoribosyltransferase (HGprt), housekeeping enzyme responsible for recycling purines, lead to Lesch-Nyhan disease (LND). Clinical expression of LND indicates that HGprt deficiency has adverse effects on gastrointestinal motility. Therefore, we aimed to evaluate intestinal motility in HGprt knockout mice (HGprt(−)). Spontaneous and neurally evoked mechanical activity was recorded in vitro as changes in isometric tension in circular muscle strips of distal colon. HGprt(−) tissues showed a lower in amplitude spontaneous activity and atropine-sensitivity neural contraction compared to control mice. The responses to carbachol a…

Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isol…

2018

[EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activatio…

Update and guidance on management of myopia : European Society of Ophthalmology in cooperation with International Myopia Institute

2021

The prevalence of myopia is increasing extensively worldwide. The number of people with myopia in 2020 is predicted to be 2.6 billion globally, which is expected to rise up to 4.9 billion by 2050, unless preventive actions and interventions are taken. The number of individuals with high myopia is also increasing substantially and pathological myopia is predicted to become the most common cause of irreversible vision impairment and blindness worldwide and also in Europe. These prevalence estimates indicate the importance of reducing the burden of myopia by means of myopia control interventions to prevent myopia onset and to slow down myopia progression. Due to the urgency of the situation, t…

Influence of digoxin on sinus node function after pharmacologic autonomic blockade.

1983

The effect of iv digoxin on normal sinus node function was studied after pharmacologic autonomic blockade (AB) in ten patients. Sinus cycle length (SCL), sinus node recovery time (SNRT) and sinoatrial conduction time (SACT) were determined before and after AB with propranolol (0.2 mg/kg body weight) and atropine sulfate (0.04 mg/kg body weight) iv, and 15 min, 30 min, and 45 min after 1 mg iv digoxin. AB resulted in a significant decrease (P less than 0.01) in SCL (916 +/- 158 to 716 +/- 120 ms), in SNRT (1,229 +/- 221 to 871 +/- 190 ms), and in SACT (79 +/- 34 to 44 +/- 10 ms). Fifteen minutes after iv digoxin there was no significant change observed in SCL (716 +/- 120 to 708 +/- 92 ms), …

Nonlinear coupling is absent in acute myocardial patients but not healthy subjects.

2008

We investigated whether autonomic nervous system imbalance imposed by pharmacological blockades and associated with acute myocardial infarction (AMI) is manifested as modifications of the nonlinear interactions in heart rate variability signal using a statistically based bispectrum method. The statistically based bispectrum method is an ideal approach for identifying nonlinear couplings in a system and overcomes the previous limitation of determining in an ad hoc way the presence of such interactions. Using the improved bispectrum method, we found significant nonlinear interactions in healthy young subjects, which were abolished by the administration of atropine but were still present afte…

Myopia, the challenge of Ophthalmology and its worldwide “explosive epidemic”

2018

Effect of histamine and histamine analogues on human isolated myometrial strips.

1992

1. The effect of histamine and histamine H1- and H2-receptor agonists on isolated myometrium strips of premenopausal women has been examined. The effect of acetylcholine was also determined. 2. Histamine, 2-pyridylethylamine, 4-methylhistamine and acetylcholine, but not dimaprit, produced a concentration-related contractile response in human isolated myometrial strips. Histamine also produced a further contraction in human isolated myometrial strips precontracted with KCl (55 mM). 3. The contractile response to histamine was antagonized by the histamine H1-receptor antagonist, clemizole (0.1 microM) but was potentiated by the histamine H2-receptor antagonist, ranitidine (10 microM). Clemizo…

Phase III Randomized Trial of FOLFIRI Versus FOLFOX4 in the Treatment of Advanced Colorectal Cancer: A Multicenter Study of the Gruppo Oncologico Del…

2005

Purpose We performed this phase III study to compare the irinotecan, leucovorin (LV), and fluorouracil (FU) regimen (FOLFIRI) versus the oxaliplatin, LV, and FU regimen (FOLFOX4) in previously untreated patients with advanced colorectal cancer. Patients and Methods A total of 360 chemotherapy-naive patients were randomly assigned to receive, every 2 weeks, either arm A (FOLFIRI: irinotecan 180 mg/m2 on day 1 with LV 100 mg/m2 administered as a 2-hour infusion before FU 400 mg/m2 administered as an intravenous bolus injection, and FU 600 mg/m2 as a 22-hour infusion immediately after FU bolus injection on days 1 and 2 [LV5FU2]) or arm B (FOLFOX4: oxaliplatin 85 mg/m2 on day 1 with LV5FU2 regi…

Cardiovascular control and time domain granger causality: Insights from selective autonomic blockade

2013

We studied causal relations among heart period (HP), systolic arterial pressure (SAP) and respiration (R) according to the definition of Granger causality in the time domain. Autonomic pharmacological challenges were used to alter the complexity of cardiovascular control. Atropine (AT), propranolol and clonidine (CL) were administered to block muscarinic receptors, β-adrenergic receptors and centrally sympathetic outflow, respectively. We found that: (i) at baseline, HP and SAP interacted in a closed loop with a dominant causal direction from HP to SAP; (ii) pharmacological blockades did not alter the bidirectional closed-loop interactions between HP and SAP, but AT reduced the dominance of…

Role for NK1 and NK2 receptors in the motor activity in mouse colon

2007

The present study examined the effects induced by endogenous and exogenous activation of NK(1) and NK(2) receptors on the mechanical activity of mouse proximal colon. Experiments were performed in vitro recording the changes in intraluminal pressure from isolated colonic segments. Electrical field stimulation in the presence of atropine and guanethidine produced a small relaxation, followed by nonadrenergic noncholinergic (NANC) contraction. SR140333, NK(1) receptor antagonist, or SR48968, NK(2) receptor antagonist, significantly reduced the contraction, although SR48968 appeared more efficacious. The co-administration of SR140333 and SR48968 virtually abolished the NANC contraction. [Sar(9…