Drugs online research references
Biochem Pharmacol. 1995 Mar 1;49(5):739-41.
Structure-activity relationships of alkylamines that inhibit rat liver hydroxysteroid sulfotransferase activities in vitro.
Matsui M, Takahashi M, Miwa Y, Motoyoshi Y, Homma H.
Kyoritsu College of Pharmacy, Tokyo, Japan.
Tetraalkylammonium salts having n-propyl to n-amyl side chains inhibited rat liver sulfotransferase (ST) activities toward dehydroepiandrosterone and cortisol, but not ST activity toward 2-naphthol, whereas trialkylamines having ethyl to n-amyl side chains inhibited ST activity toward dehydroepiandrosterone, but not ST activities toward cortisol and 2-naphthol. A comparison of I50 values, which represent inhibitor concentration resulting in 50% inhibition of dehydroepiandrosterone ST activity, revealed that the values for the tetraalkylammonium salts were 0.015 to 0.017 mM, whereas the values for the trialkylamines were 0.20 to 0.33 mM. Introduction of hydrophilic groups such as hydroxyl, thiol, nitrile and acetamide groups or substitution by methyl and allyl groups in the alkyl side chains markedly diminished the inhibitory effect of triethylamine. These data indicate that ethyl to n-amyl side chains are a prerequisite for the alkylamine-type inhibitor. Tertiary amine drugs such as imipramine, dimenhydrinate, cyclizine, chlorpromazine and promethazine inhibited ST activities toward dehydroepiandrosterone and cortisol similar to the tetraalkylammonium salts, although the drugs were weaker inhibitors of hydroxysteroid ST activities. These results imply that in addition to trialkylamine side chains, the other portion of the drugs may participate in the inhibition of hydroxysteroid ST activities.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7887990&dopt=Abstract
Eur J Pharmacol. 1994 Jan 1;266(1):99-102.
Inhibition by histamine H1 receptor antagonists of endogenous glibenclamide-sensitive K+ channels in follicle-enclosed Xenopus oocytes.
Sakuta H.
Department of Pharmacology, National Defense Medical College, Saitama, Japan.
Effects of histamine receptor ligands on the glibenclamide-sensitive K+ currents induced by K+ channel openers, cromakalim and Y-26763, were examined in follicle-enclosed Xenopus oocytes. Histamine H1 receptor antagonists, promethazine, dimethindene and chlorpheniramine all decreased cromakalim-induced K+ currents with IC50 values of 31.5 microM, 29.5 microM and 138 microM, respectively. These compounds also blocked Y-26763-induced K+ currents with comparable IC50 values. Histamine (1 mM) and histamine H2 receptor antagonists, cimetidine (0.5 mM) and ranitidine (1 mM) had little effect on these K+ currents. These results suggest that histamine H1 receptor antagonists inhibit glibenclamide-sensitive K+ currents by a mechanism other than the histamine H1 receptor antagonism. The inhibitory effects might explain, in part, the reported actions of histamine H1 receptor antagonists in ischemia.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7907990&dopt=Abstract
Arzneimittelforschung. 1994 Mar;44(3):327-9.
Inhibitory effect of epinastine on bronchoconstriction induced by histamine, platelet activating factor and serotonin in guinea pigs and rats.
Tasaka K, Kamei C, Nakamura S.
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Okayama University, Japan.
Effects of epinastine ((+/-)-3-amino-9,13b-dihydro-1H-dibenz[c,f]imidazo[1,5-a]azepine hydrochloride, WAL 801 CL, CAS 80012-43-7) and reference drugs on bronchoconstriction induced by histamine, platelet activating factor (PAF) and serotonin were studied in guinea pigs and rats. Oral administration of epinastine resulted in a potent inhibition on bronchoconstriction induced by all three bronchoconstrictor agents, and especially, an inhibitory effect on histamine-induced response was remarkable. The effect of epinastine was stronger than that of ketotifen in inhibiting the responses induced by both PAF and serotonin. However, the extent of inhibition in the latter was less remarkable than that seen after histamine. Azelastine was 1.36-4.57 times less potent than epinastine in inhibiting the bronchoconstriction induced by either bronchospasmogen. Although promethazine displayed inhibitory effects on the responses induced by histamine, PAF and serotonin, the inhibiting potency was distinctly inferior to that of epinastine.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7910745&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 ||