Inhibition dihydropyridines

Duarte CB, Rosario LM, Sena CM, Carvalho AR A toxin fraction (FTX) from the funnel-web spider poison inhibits dihydropyridine-insensitive Ca channels coupled to catecholamine release in bovine adrenal chromaffin cells. J Neurochem 1993 60(3) 908-13. 

Hypertension Calcium channel blockers ACE inhibitors ARBs Diltiazem, verapamil inhibit CSA/TAC metabolism Dihydropyridines may potentiate CSA-gingival hyperplasia May exacerbate hyperkalemia monitor K+, SCr to assess for renal allograft vascular disease may be useful in posttranplant erythrocytosis (hematocrit greater than 55%)... 

Kostic, D. et al. (1995). Intestinal absorption, serum clearance, and interactions between lutein and beta-carotene when administered to human adults in separate or combined oral doses. Am. J. Clin. Nutr. 62 604—610. Kuo, S. M. et al. (2001). Dihydropyridine calcium channel blockers inhibit ascorbic acid accumulation in human intestinal Caco-2 cells. Life Sci. 68(15) 1751-1760. 

Similar to dihydropyridine calcium blockers, many 0-adrenoreceptor antagonists exhibit antioxidant activity. Mak and Weglinski [290] showed that the pretreatment of canine myocytic sarcolemmal membranes with 0-adrenoreceptor antagonists (propranolol, pindolol, metoprolol, atenolol, or sotalol) (Figure 29.15) inhibited superoxide-induced sarcolemmal... 

Sevanian, A., Shen, L., and Ursini, P., 2000, Inhibition of LDL oxidation and oxidized LDL-induced cytotoxicity by dihydropyridine calcium antagonists, Pbami. Res. 17 999-1006. 

Wang Z, Watanabe S, Kobayashi Y, Tanaka M, Matsui T. (2010) Trp-His, a vasorelaxant di-peptide, can inhibit extracellular Ca entry to rat vascular smooth muscle cells through blockade of dihydropyridine-like L-type Ca channels. Peptides 31 2060-2066. 

Bepridil also inhibits fast sodium inward channels. Galcium channel blockers are classified by structure as follows Diphenylalkylamines - verapamil benzothiazepines - diltiazem dihydropyridines - amlodipine, felodipine, isradipine, nicardipine, nifedipine, nimodipine, nisoldipine. 

Diltiazem and verapamil inhibit other CYP3A4 substrates, whereas the dihydropyridines do not. 

Meyer EB, Tally PW, Anderson RE, et al Inhibition of electrically induced seizures by a dihydropyridine calcium channel blocker. Brain Res 384 180-183, 1986 Meyer HH, Gottlieb R Theory of narcosis, in Experimental Pharmacology as a Basis for Therapeutics, 2nd Edition. Translated by Henderson VE. Philadelphia, PA, JB Lippincott, 1926, pp 116-29... 

Lehn and coworkers have profitably employed tartaric acid-containing crown ethers as enzyme models. The rate of proton transfer to an ammonium-substituted pyridinium substrate from a tetra-l,4-dihydropyridine-substituted crown ether was considerably enhanced compared to that for a simple 1,4-dihydropyridine. The reaction showed first order kinetic data and was inhibited by potassium ions. Intramolecular proton transfer from receptor to substrate was thus inferred via the hydrogen bonded receptor-substrate complex shown in Figure 16a (78CC143). 

Carbanions, such as that from malonodinitrile, generate dienes (66) which ring-close to iV-acyl-l,2-dihydropyridines (67). Subsequently these products may rearrange to 2-amidopyridines (Scheme 21) (75BCJ73). However, if substituted malonodinitriles are employed in this reaction the intermediate 6H-1,3-oxazines can be isolated for now deprotonation and ring opening are inhibited. 

Hopf, F.W., Reddy, P., Hong, J., and Steinhardt, R.A., 1996a, A capacitative calcium current in cultured skeletal muscle cells is mediated by the calcium-specific leak channel and inhibited by dihydropyridine compounds, J Biol Chem, 271, pp 22358-22367. 

Neither the increase in cytosolic [Ca2+] nor the associated cell retraction or inhibition of bone resorption appear to involve voltage-dependent L-type Ca2+ channels. These were largely insensitive to both dihydropyridine or phenylalky-lamine Ca2+ channel specific reagents even under depolarizing conditions (Datta et al., 1990 see also Zaidi et al., 1990). The available evidence favours specialist cellular mechanisms that sense ambient [Ca2+] that parallel situations described in... 

Calcium channel blockers (CCBs) prevent the flow of calcium ions through channels in heart tissue. Inhibiting calcium flow decreases the strength of contraction of the heart and decreases blood pressure. Most CCBs fall into the dihydropyridine structural class, with nifedipine (Adalat, A.132) being the prototypical example (Figure A.38). Nondihydropyridine CCBs include diltiazem (Cardizem, A.135) and verapamil (Calan, A.136). 

Non-dihydropyridine caldumantagonist (Class IV MD) that inhibits the calcium mediated depolarization of the AV-node, increasing the nodal effective refractory period and reducing ventricular rate in AF... 

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