objective(s) four novel losartan analogues 5a-d were synthesized by connecting a dihydropyridine nucleus to imidazole ring. the effects of 5a and 5b on angiotensin receptors (at') and l-type calcium channels were investigated on isolated rat aorta. materials and methods aortic rings were pre-contracted with 1 pm angiotensin ii or 80 mm kcl and relaxant effects of losartan, nifedipine, 5a a...

Polyclonal antibodies to the 32,000-Da polypeptide of the 1,4-dihydropyridine receptor of the voltage-dependent Ca2+ channel have been produced and used to characterize the association of the 32,000-Da polypeptide (gamma subunit) with other subunits of the dihydropyridine receptor. The 32,000-Da polypeptide was found to copurify with alpha 1 and alpha 2 subunits at each step of the purification...

a series of 1,4-dihydropyridine calcium channel blockers bearing 1-(4-x -benzyl)-5-imidazolyl substituent at 4 position (5a-e) (x=h, f) were synthesized and tested for antihypertensive activity in desoxycorticosterone acetate (doca)-induced hypertension in rats. amlodipine was used as the standard dihydropyridine. all compounds tested showed lower antihypertensive activity than that of amlodipi...

Nicardipine hydrochloride (Nic), a calcium channel antagonist, is used for the treatment of hypertension. In the present study, we estimated its effects on the levels and activities of hepatic cytochrome P450 isoforms in spontaneously hypertensive rats given p.o. with Nic at a dose of 0.5, 2.5, 5, or 12.5 mg/kg at 24-hr intervals for 14 days. Therapeutic effects on the development of hypertensi...

The experiment was conducted to investigate the effects of dihydropyridine on laying performance and fat metabolism of laying hens. Five hundred and forty laying hens, 40 weeks old, were randomly allotted to three groups, each of which included four replicates of 45 hens. The groups were given a basal corn-soybean meal diet supplemented with 0, 150 mg/kg and 300 mg/kg dihydropyridine. Results s...

Isothiazolopyridines, pyridothiazines and pyridothiazepines are important compounds that possess valuable biological activities. This paper reports on the synthesis of these compounds using both conventional chemical methods and modern microwave techniques. 3-Bromo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide, 5-arylazo-6-hydroxy-4-methyl-2-thioxo-1,2-dihydropyridine-3-carboxam...

Abstract: Amlodipine is a dihydropyridine calcium channel blocker mainly indicated in the treatment of essential hypertension and angina pectoris. Overdose blocker, results toxicity along with profound hypotension shock. Here, 20-year-old female patient was admitted to MICU complaints severe breathing difficulty, multiple episodes vomiting one day earlier. After chest x-ray, ECG, blood investig...

In the title compound, C(18)H(17)N(3), the dihedral angle between the dihydropyridine and phenyl rings is 72.57 (5)° and that between the dihydropyridine ring and malononitrile plane is 5.19 (20)°. The C-C bond lengths in the pyridine ring are considerably shorter than those of normal single bonds, indicating that electrons on the dihydropyridine ring, including the non-bonding electrons of the...

Various 1and 2-substituted and 1,2-fused 1,4-dihydropyridine-5-phosphonate derivatives were designed and synthesized as analogues of 1,4-dihydropyridine-3,5-dicarboxylate, and their antihypertensive activities were examined. Several compounds proved to be equal or superior to nifedipine in lowering blood pressure in normotensive and spontaneously hypertensive rats. Among these compounds, 1-subs...

The dihydropyridine Ca2+ antagonist drugs used in the therapy of cardiovacular disorders inhibit L-type Ca2+ channels by binding to a single high affinity site. Photoaffinity labeling and analysis of mutant Ca2+ channels implicate the IIIS6 and IVS6 segments in high affinity binding. The amino acid residues that are required for high affinity binding of dihydropyridine Ca2+ channel antagonists ...