Drugs online research references
J Cardiovasc Pharmacol. 1987;10 Suppl 9:S27-34.
Effects of alpha 1-inhibition on lipid metabolism in the rat.
Woodside WF, Swindell AC.
Department of Pharmacology, University of New Mexico Medical School, Albuquerque 87131.
Prazosin or doxazosin, selective alpha 1-adrenergic receptor inhibitors used in the treatment of hypertension, are known from clinical studies to lower plasma lipids. When diets and dosing regimens are carefully controlled, both agents produce similar effects on plasma lipids in rats, i.e., decreases in triglycerides and in the non-high density lipoprotein (non-HDL) fraction of cholesterol. In order to conduct these studies, models of rats partially fasting (PF) and eating a high-sucrose diet were developed. The effects of prazosin 2.3 mg/kg/day and doxazosin 20 mg/kg/day on plasma levels of triglycerides, total and HDL cholesterol, free fatty acids (FFA), ketones, and other metabolites were measured in rats in the fed, fasting, or PF states, at various times after a meal, and with a high-cholesterol diet. The pattern of responses leads to the hypothesis that, under conditions of partial or complete fasting, alpha 1-adrenergic receptor inhibition can alter intrahepatic FFA metabolism, causing increased ketogenesis and diminished triglyceride synthesis, possibly through potentiation of beta-adrenergic or related pathways. If these concepts prove to be valid in humans, they suggest that factors such as the rate of very-low-density lipoprotein (VLDL) production or the state of sympathetic nervous activity may influence the changes in lipids induced by these agents.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2447438&dopt=Abstract
J Cardiovasc Pharmacol. 1987;10 Suppl 9:S35-41.
Studies with doxazosin on the saturable binding of 125I-LDL by liver in normocholesterolemic mice.
Nanjee MN, Miller NE.
Department of Chemical Pathology and Metabolic Disorders, St. Thomas' Campus, United Medical School of Guy's Hospital, London, U.K.
Tissue culture studies have provided evidence that alpha 1-adrenergic receptor inhibition with doxazosin increases the number of low-density lipoprotein (LDL) receptors in human fibroblasts. A similar effect occurring in vivo might explain the reduction of plasma LDL concentration observed in some clinical trials of prazosin. In order to examine this question further, mice were given doxazosin 100 or 400 micrograms/kg/day by i.p. injection for 4 days, after which they were killed, blood was collected and livers were excised. Binding of 125I-labelled human LDL to tissue homogenates, over the concentration range 30-120 micrograms LDL protein/ml, was measured at 37 degrees C in the absence and presence of excess unlabelled LDL. Woolf plots of the results for saturable binding were found to be compatible with a single class of binding site. In control animals Bmax for this receptor was 867 +/- 117 ng LDL protein/mg tissue protein, and the equilibrium dissociation constant was 32.7 +/- 6.6 micrograms LDL protein/ml (mean +/- SD, n = 5). Doxazosin treatment had no effect on either parameter of 125I-LDL binding. A trend towards a decrease in liver triglyceride concentration with increasing doses of doxazosin was recorded, but there was no evidence for effects on liver cholesterol or serum lipid concentrations.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2447439&dopt=Abstract
J Cardiovasc Pharmacol. 1988 Mar;11(3):373-7.
Action of dopamine on isolated human saphenous veins.
Hughes A, Inkpen P, Sever P.
Department of Clinical Pharmacology, St. Mary's Hospital Medical School, London, England.
We have investigated the subtype of alpha-adrenoceptor responsible for the contractile effect of dopamine using isolated human saphenous vein. Lengths of saphenous vein were obtained surplus to coronary artery bypass graft operations and studied as intact rings using a conventional organ bath technique. Contractile responses to dopamine (10(-7)-10(-3) M) in the presence of propranolol, cocaine, and 17 beta oestradiol were competitively antagonised by the alpha 2-selective adrenoceptor antagonist yohimbine (10(-8)-10(-6) M) but unaffected by the alpha 1 selective adrenoceptor antagonist doxazosin (10(-8)-10(-6) M), whereas the response to norepinephrine (NE) (10(-8)-10(-3) M) was antagonised by doxazosin (10(-8)-10(-6) M), thus demonstrating the presence of alpha 1-adrenoceptors in this preparation. We conclude that the contractile effects of dopamine in isolated human saphenous vein are mediated predominantly by an action on alpha 2-adrenoceptors.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2452932&dopt=Abstract
online pharmacies ||
Hair Million herbal formula for hair loss and hair growth ||
Amoxicillin ||
Tramadol ||
Paxil ||
Rx Drugs USA, Prescription Drugs Online Pharmacy ||
Zithromax ||
online pharmacy ||
Antibiotics and prescription medications online literature ||
Antibiotics