Search results for "INHIBITORS"
showing 10 items of 2336 documents
Effects of Long-Term Nitroglycerin Treatment on Endothelial Nitric Oxide Synthase (NOS III) Gene Expression, NOS III–Mediated Superoxide Production, …
2000
Abstract —Long-term nitroglycerin (NTG) treatment has been shown to be associated with cross-tolerance to endothelium-dependent vasodilators. It may involve increased production of reactive oxygen species (such as superoxide, O 2 ·− ) that rapidly inactivate the nitric oxide (NO) released from the endothelial cells. It remains to be elucidated, however, whether long-term treatment with NTG alters the activity and expression of the endothelial NO synthase (NOS III) and whether this enzyme can contribute to O 2 ·− formation. We studied the influence of long-term NTG treatment on the expression of NOS III as assessed by RNase protection assay and Western blot. Tolerance was measured ex vivo i…
Effects of diazinon exposure on cholinesterase activity in different tissues of European eel (Anguilla anguilla).
1996
Cholinesterase (ChE) activity was measured in brain, plasma, and whole eye of Anguilla anguilla experimentally exposed to a sublethal concentration of 0.042 mg/liter (0.50 of the 96-hr LC50) of the organophosphorous pesticide diazinon. Whole eye was the tissue which revealed higher values of ChE activity (8.17 micromol/min/g) in nonexposed animals. Brain, plasma, and whole eye ChE activity of A. anguilla was inhibited at 6, 24, 48, 72, and 96 hr of diazinon exposure. Pesticide induced significant inhibitory effects on the ChE activity of this species ranging from >70% inhibition in brain tissue to >90% in plasma samples. Brain and plasma presented technical difficulties in their collection.…
In vivo inhibition of AChE activity in the European eel Anguilla anguilla exposed to technical grade fenitrothion.
1998
European eel (Anguilla anguilla) were exposed to sublethal fenitrothion concentrations in a continuous flow-through system for 4 days. Plasma acetylcholinesterase (AChE) activity was evaluated after 2, 8, 12, 24, 32, 48, 56, 72 and 96 h pesticide exposure. AChE activity in the plasma of the eel decreased as concentration of fenitrothion increased. Pesticide induced significant inhibitory effects on the AChE activity of A. anguilla ranging from 51% inhibition at sublethal concentration of 0.02 ppm to 57% inhibition at sublethal concentration of 0.04 ppm. Eel were exposed to both fenitrothion concentrations for 96 h and then allowed a period of recovery in pesticide-free water. Following 1 we…
LEUKOTRIENE RECEPTORS ON HUMAN PULMONARY VASCULAR ENDOTHELIUM
1995
1. Cysteinyl-leukotrienes cause contractions and/or relaxations of human isolated pulmonary vascular preparations. Although, the localization and nature of the receptors through which these effects are mediated have not been fully characterized, some effects are indirect and not mediated via the well-described LT1 receptor. 2. In human pulmonary veins (HPV) with an intact endothelium, leukotriene D4 (LTD4) induced contraction above basal tone. This response was observed at lower concentrations of LTD4 in the presence of nitric oxide synthase inhibitor N omega-nitro-L-arginine (L-NOARG). Contractions (in the absence and presence of L-NOARG) were partially blocked by the LT1 antagonists (MK 5…
The phototransduction cascade in the isolated chick pineal gland revisited.
2003
It is well established that the isolated chick pineal gland is directly light sensitive and that melatonin synthesis of the gland can be inhibited by exposing the gland to light during scotophase. Since not all the steps of the phototransduction cascade have been clarified to the same extent as in the retina, we have treated isolated chick pineal glands with 90 min of light during scotophase and with drugs that affect key-components of vertebrate phototransduction, i.e., cyclic guanosine monophosphate (cGMP) phosphodiesterase 6 (PDE6), cGMP levels and cGMP-gated calcium channels. The endpoint measured was the activity of the rate-limiting enzyme of melatonin synthesis, arylalkylamine N-acet…
Adipokines and Lipoproteins: Modulation by Antihyperglycemic and Hypolipidemic Agents
2014
Abstract Adipose tissue is an endocrine organ that secretes a number of hormones and metabolically active substances that impact energy metabolism and insulin sensitivity. These inflammatory markers are collectively referred to as adipocytokines, or adipokines. Adipose tissue's functional capacity and metabolic activity vary among individuals, thus partly explaining the incomplete overlap between obesity and the metabolic syndrome. The functional failure of adipose tissues results in changed energy delivery and impaired glucose consumption, triggering self-regulatory mechanisms to maintain homeostasis. Antihyperglycemic, hypolipidemic, antiobesity, and angiotensin II receptor blocker drugs …
Incretin-Based Therapies, Glucometabolic Health and Endovascular Inflammation
2013
Incretin peptides are a group of gastrointestinal hormones that play a prominent role in the regulation of glucose metabolism. Incretin-based therapies (IBTs) have recently emerged as an important treatment option for patients with type 2 diabetes mellitus (T2DM). These pharmaceutical agents may be specially well suited for patients who are overweight or obese with primarily post-meal glucose peaks, and in whom traditional first-line oral agents have failed to maintain adequate glycemic control. There are 2 classes of IBTs: the dipeptidyl peptidase-4 (DPP-4) inhibitors and the glucagon-like peptide 1 (GLP-1) receptor agonists. The ultimate effect of both types of agents is to augment GLP-1 …
Type 2 diabetes, dyslipidemia, and vascular risk: rationale and evidence for correcting the lipid imbalance.
2004
Type 2 diabetes is an important cardiovascular risk factor. A significant component of the risk associated with type 2 diabetes is thought to be because of its characteristic lipid "triad" profile of raised small dense low-density lipoprotein levels, lowered high-density lipoprotein, and elevated triglycerides (TGs). Trials of statins and fibrates have included substantial numbers of patients with diabetes and indicate that lipid lowering reduces cardiovascular event rates in these patients. However, statins alone do not always address all the lipid abnormalities of diabetes. Fibrates, which have low affinity for peroxisome proliferator-activated receptor alpha (PPARalpha), improve most asp…
Elevated Expression of Liver γ-Cystathionase Is Required for the Maintenance of Lactation in Rats
1999
Liver gamma-cystathionase activity increases in rats during lactation; its inhibition due to propargylglycine is followed by a significant decrease in lactation. This is reversible by N-acetylcysteine administration. To study the role of liver gamma-cystathionase and the intertissue flux of glutathione during lactation, we used lactating and virgin rats fed liquid diets. Virgin rats were divided into two groups as follows: one group was fed daily a diet containing the same amount of protein that was consumed the previous day by lactating rats (high protein diet-fed rats); the other virgin group was fed the normal liquid diet (control). The expression and activity of liver gamma-cystathionas…
Low-density lipoprotein size and cardiovascular risk assessment
2017
A predominance of small, dense low-density lipoproteins (LDL) has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart disease and evidences suggests that both quality (particularly small, dense LDL) and quantity may increase cardiovascular risk. However, other authors have suggested that LDL size measurement does not add information beyond that obtained by measuring LDL concentration, triglyceride levels and HDL concentrations. Therefore, it remains debatable whether to measure LDL particle size in cardiovascular …