Drugs online research references
Arzneimittelforschung. 1993 Mar;43(3):320-3.
In vitro and in vivo studies on slow release propranolol hydrochloride suppositories. Pharmacokinetic and pharmacodynamic evaluation.
Sastri MS, Satyanarayana NV, Krishna DR, Diwan PV.
Pharmacology Section, Indian Institute of Chemical Technology, Hyderabad.
Matrix-based slow release (SR) compressed propranolol HCl (25 mg) suppositories were formulated using PEG 4000 and either stearic acid or bees wax at different concentrations (5, 7.5 and 10%). In vitro studies revealed good slow release characteristics from the suppositories. Their in vivo performances--pharmacokinetics and pharmacodynamics--were evaluated in rabbits. Different pharmacokinetic parameters were determined from the plasma concentration-time profiles using a model-independent computer programme, RAMKIN. The relative bioavailability of propranolol (CAS 525-66-6) from three SR suppositories containing stearic acid, 7.5 and 10% and bees wax, 5%, was 86.4, 87.8, and 83.6% respectively. Pharmacodynamic response (beta-blockade) was assessed by determining the degree of reduction of isoprenaline-induced tachycardia at different time intervals. A minimum concentration of 40-60 ng/ml drug in plasma was maintained during 1-10 h, and there has been a minimum of about 40-50% of beta-blockade during 1-9 h post administration. A good correlation between pharmacokinetic and pharmacodynamic profiles was observed.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8489559&dopt=Abstract
FEBS Lett. 1993 May 24;323(1-2):23-6.
Enhancement of phospholipase A2 activation by phosphatidic acid endogenously formed through phospholipase D action in rat peritoneal mast cell.
Sato T, Ishimoto T, Akiba S, Fujii T.
Department of Biochemistry, Kyoto Pharmaceutical University, Japan.
Contribution of phosphatidic acid (PA) generated by activated phospholipase (PL) D to PLA2 activation was studied in rat peritoneal mast cells. Exogenous didecanoyl PA induced arachidonate liberation in the permeabilized cells which was inhibited by p-bromophenacyl bromide. Upon exposure of the cells to ethanol in a high enough concentration to prevent PA formation, A23187-induced arachidonate liberation was suppressed by 50% and the rest was completely inhibited by p-bromophenacyl bromide. In contrast, propranolol, which enhanced PA accumulation, significantly increased the arachidonate liberation. These results suggest that A23187-induced PLA2 activation may be potentiated, at least in part, by PA generated through PLD action.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8495740&dopt=Abstract
Dig Dis Sci. 1985 Jul;30(7):664-8.
Effect of substance P on opossum duodenal smooth muscle.
Nowak TV, Anuras S.
Opossum duodenum was cut into strips measuring 2.0 X 15.0 mm. Strips cut along the oral-caudal axis were called longitudinal strips, while those cut 90 degrees to that axis were called circular strips. Each strip was placed in a heated, oxygenated organ bath and attached to a force-displacement transducer. Substance P produced tonic contraction in longitudinal strips and tonic and phasic contraction in circular strips. The ED50 for longitudinal and circular muscle was 1.9 X 10(-7) M and 2.8 X 10(-7) M, respectively. Longitudinal muscle was 1.3 times more sensitive to substance P than circular muscle. Phenoxybenzamine, atropine, curare, propranolol, haloperidol, and tetrodotoxin had no effect on the substance P-produced contractions in circular and longitudinal muscle. Trifluoperazine (10(-5) and 10(-4) M), D600 (10(-7) M), and nifedipine (10(-8) and 10(-7] inhibited both tonic and phasic contraction in circular and longitudinal strips. These studies suggest that substance P acts on both muscle layers at a site located at the muscle cell and that it produces tonic and phasic contraction through similar calcium-activating pathways.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2408832&dopt=Abstract
Herbs and Pharmaceuticals Online ||
Hair Million herbal formula for hair loss and hair growth ||
Wellstreet online pharmacy for click-order prescription medications ||
Altace Online Pharmacy ||
Rx Drugs USA, Prescription Drugs Online Pharmacy ||
Insurance plans and information ||
Insurance policies for all purposes ||
Antibiotics and prescription medications online literature ||