Vasodilatory agent

Viprostol (81) also incorporates a hydroxy group moved to C-16 and protects this from facile metabolic oxidation by vinylation. It is a potent hypotensive and vasodilatory agent both orally and transdermally. The methyl ester moiety is rapidly hydrolyzed in skin and in the liver so it is essentially a prodrug. It is synthesized from protected E-iodo olefin 78 (compare with 75) by conversion to the mixed organocuprate and this added in a 1,4-sense to olefin 79 to produce protected intermediate 80. The synthesis of viprostol concludes by deblocking with acetic acid and then reesterification with diazomethane to give 81 [19]. 

The direct injection of potent vasodilatory agents such as papaverine or isosor-bide dinitrate, into the ventricles of the heart reverses the action of palytoxin in approximately one-half of the animals. These extreme measures are required because palytoxin kills quickly. Antidotes injected into the venous circulation were not able to reach the heart because the stagnation of venous blood occurs so rapidly that antidotes are simply pooled on the venous side of the circulation and never reach the heart. In these studies isosorbide dinitrate appeared to be approximately twice as effective as papaverine in reversing the toxic effects of palytoxin. 

Vasodilatory agent, 13 Verapamil, 34 Viprostol, 13 Vitamin A aeetate, 7 Von Braun reaetion, 30... 

As well as their chemical importance, appropriate oxy-1,6-naphthyridines have shown appreciable (but not outstanding) biological activities as metal-binding antibacterials,110 or as antineoplastic agents.572,cf 843 Medorinone, 5-methyl-1,6-naphthyridin-2(lH)-one, has been used as a cardiotonic/vasodilatory agent.490, 716,1224,cf. 320 QXy derivatives of fused/unfused 1,6-naphthyridines have been iso-lated from manne sponges. ... 

The rate of removal of the local anesthetic from the site of injection also affects its profile. AH local anesthetic agents possess some vasodilatory activity at clinically useful concentrations. Agents which are more potent in this regard tend to be absorbed more rapidly by the vasculature. They are less potent anesthetics and have shorter durations than those having lower vasodilatory activity. A comparison of potency, onset, and duration as a function of physiochemical properties is presented in Table 4. 

In vivo, lacidipine -when administered orally - was found to be an effective and potent antihypertensive agent in different animal models, including SHR (ED25 = 0.5 mg kg-1, per os) and renally hypertensive dogs (ED25 = 0.004 mg kg-1, i.v.) with a sustained duration of action [11,12]. Lacidipine was also found to possess coronary and cerebral vasodilatory activity [13]. 

Dipyridamole (peisantine), a vasodilatory and antiplatelet agent, has been widely used clinically tor many yeais (54). Dipyridamole is a weak inhibitor of cAMP PDB 20 pM) (55), whereas,... 

Kakoki M, Hirata Y, Hayakawa H, Suzuki E, Nagata D, Nishimatsu H, Kimura K, Goto A, Omata M Effects of vasodilatory antihypertensive agents on endothelial dysfunction in rats with ischemic acute renal failure. Hypertens Res 23 527-33, 2000... 

A-Acetylcysteine is administered in the ace-toaminophen toxicity. It replenishes the hepatic stores of glutathione (Chapter 17). A-Acetylcysteine is also used in the treatment of pulmonary diseases including cystic fibrosis (Chapter 12). In patients with chronic renal insufficiency, prophylactic oral administration of A-Acetylcysteine have been used in the prevention of further renal impairment due to administration of radiographic contrast agents. In this setting presumably A-Acetylcysteine functions as an antioxidant and augments the vasodilatory effect of nitric oxide via the formation of S-nitrosothiol (Chapter 17). 

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