Pentaerythritol tetranitrate is an organic nitrate that has been used for the treatment of angina pectoris. Upon administration, the drug undergoes exstensive metabolism to NO which causes vasodilation and the relaxation of smooth muscle cells. The compound belongs to a familiy of explosive substances and may be used accordingly.

Omecamtiv mecarbil (CK-1827452) is a specific cardiac myosin activator and a clinical drug for left ventricular systolic heart failure (in Phase 2 of development). Omecamtiv mecarbil is an inotropic agent that prolongs systolic ejection time and increases ejection fraction through myosin ATPase activation.

Kynurenine is a metabolite of the amino acid L-tryptophan used in the production of niacin. Kynurenine is synthesized by the enzyme tryptophan dioxygenase, which is made primarily but not exclusively in the liver, and indoleamine 2,3-dioxygenase, which is made in many tissues in response to immune activation. Kynurenine and its further breakdown products carry out diverse biological functions, including dilating blood vessels during inflammation and regulating the immune response. Evidence suggests that increased kynurenine production may precipitate depressive symptoms associated with interferon treatment for hepatitis C. Cognitive deficits in schizophrenia are associated with imbalances in the enzymes that break down kynurenine. Kynurenine production is increased in Alzheimer's disease and cardiovascular disease where its metabolites are associated with cognitive deficits and depressive symptoms.

Thiorphan is the first potent synthetic inhibitor of enkephalinase. Thiorphan displays antinociceptive activity after systemic administration. Thiorphan also inhibits to a lesser extent the widely distributed angiotensin-converting enzyme, a carboxydipeptidase implicated in blood pressure regulation. Thiorphan failed to potentiate allergen-induced airway responses in asthma. Thiorphan significantly reduced the castor oil-induced diarrhea in rats when administered intravenously but not when administered intracerebroventricularly. Racecadotril, via its active metabolite thiorphan, was consistently effective in animal models and patients with various forms of acute diarrhea by inhibiting pathologic (but not basal) secretion from the gut without changing gastro-intestinal transit time or motility.

Carmoxirole is a dopamine D2 receptor agonist with limited central activity that modulates sympathetic activation and subsequently reduces pre-load and afterload in animals. It was shown, that carmoxirole induced beneficial effects on hemodynamic and neurohumoral parameters in heart failure. In addition, experimental evidence showed that carmoxirole lowered blood pressure in various models of hypertension mainly or exclusively through inhibition of noradrenaline release from sympathetic nerve endings. That effect of carmoxirole was mediated by presynaptic dopamine receptors with the characteristic that release inhibition was restricted to low rates of sympathetic nerve discharge.

Thiorphan is the first potent synthetic inhibitor of enkephalinase. Thiorphan displays antinociceptive activity after systemic administration. Thiorphan also inhibits to a lesser extent the widely distributed angiotensin-converting enzyme, a carboxydipeptidase implicated in blood pressure regulation. Thiorphan failed to potentiate allergen-induced airway responses in asthma. Thiorphan significantly reduced the castor oil-induced diarrhea in rats when administered intravenously but not when administered intracerebroventricularly. Racecadotril, via its active metabolite thiorphan, was consistently effective in animal models and patients with various forms of acute diarrhea by inhibiting pathologic (but not basal) secretion from the gut without changing gastro-intestinal transit time or motility.

Piboserod (SB 207266) is a selective 5-HT(4) receptor, antagonist. The 5-HT4 receptor antagonists are thought to antagonize both the ability of serotonin to sensitize the peristaltic reflex and 5-HT-induced defecation, at least in animal studies. As 5-HT4 receptors are present in human atrial cells and when stimulated may cause atrial arrhythmias, piboserod was under investigation in clinical trials for atrial fibrillation. In addition, GlaxoSmithKline studied the drug for the management of irritable bowel syndrome. Nevertheless, development both indications had been discontinued. Piboserod has successfully passed phase II clinical trials for the treatment of patients with congestive heart failure.

Digoxin is a cardiac glycoside derived from the purple foxglove flower. In 1785, the English chemist, botanist, and physician Sir William Withering published his findings that Digitalis purpurea could be used to treat cardiac dropsy (congestive heart failure; CHF). Digoxin has been in use for many years, but was not approved by the FDA for treatment of heart failure (HF) until the late 1990s. Another FDA indication for digoxin is atrial fibrillation (AF). Digoxin also has numerous off-label uses, such as in fetal tachycardia, supra-ventricular tachycardia, cor pulmonale, and pulmonary hypertension. Digitoxin inhibits the Na-K-ATPase membrane pump, resulting in an increase in intracellular sodium and calcium concentrations. Increased intracellular concentrations of calcium may promote activation of contractile proteins (e.g., actin, myosin). Digoxin also has Para sympathomimetic properties. By increasing vagal tone in the sinoatrial and atrioventricular (AV) nodes, it slows the heart rate and AV nodal conduction.

Evans Blue (EBD) is an azo dye which has a very high affinity for serum albumin. It can be useful in physiology in estimating the proportion of body water contained in blood plasma. Evans Blue Dye is widely used to study blood vessel and cellular membrane permeability as it is non-toxic, it can be administered as an intravital dye and it binds to serum albumin – using this as its transporter molecule. The EBD–albumin conjugate (EBA) can be: (i) identified macroscopically by the striking blue colour within tissue; (ii) observed by red auto-fluorescence in tissue sections examined by fluorescence microscopy; and (iii) assessed and quantified by spectrophotometry for serum samples, or homogenised tissue. has recently been utilised in mdx mice to identify permeable skeletal myofibres that have become damaged as a result of muscular dystrophy. EBD has the potential to be a useful vital stain of myofibre permeability in other models of skeletal muscle injury and membrane-associated fragility. Evans Blue is a potent inhibitor of L-glutamate uptake into synaptic vesicles. It also inhibits AMPA and kainate receptor-mediated currents (IC50 values are 220 and 150 nM respectively). P2X-selective purinoceptor antagonist.

Fosfructose is a cytoprotective natural sugar phosphate under development by Questcor (formerly Cypros) for the potential treatment of cardiovascular ischemia, sickle cell anemia and asthma. Fosfructose acts by stimulating anaerobic glycolysis which generates adenosine triphosphate under ischemic conditions and improve the cellular energy metabolism in ischemic and hypoperfused tissues. Hypoxia forces ischemic tissue to anaerobic glycolysis for energy, which yields two molecules of ATP per glucose in contrast to 36 molecules of ATP generated during oxidative phosphorylation . Addition of exogenous Fosfructose can produce two more molecules of ATP in an uncompensated anaerobic environment and hence facilitate the recovery of ischemia tissue. Fosfructose breaks down into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate, which will further break down into two molecules of pyruvate and finally produce two molecules of ATP. Other mechanisms include inhibition of the generation of oxygen free radicals by neutrophils, stabilization of cell membranes, and maintainance of the correct xanthine dehydrogenase/oxidase ratio by preventing the depletion of phosphorylated compounds in ischemic tissues. In myocardial infarction patients, FDP can improve the hemodynamic parameters, attenuate ECG proven ischemic injury and arrhythmia, prevent ATP and creatine phosphate depletion from ischemic myocardium, reduce infarct size, and increase survival rate. Exogenously administered Fosfructose has also been proven beneficial for a variety of other ischemic organs, such as liver, kidney, bowel and even brain as a consequence of its ability to penetrate to the blood brain barrier. Fosfructose trisodium had been in phase I clinical trials for the treatment of heart transplant rejection. Fosfructose trisodium had been in phase II clinical trials for the treatment of heart failure, perioperativ eischaemia and reperfusion injury. Fosfructose trisodium had been in phase III clinical trials for the treatment of sickle cell anaemia. However, all these research has been discontinued. In China, FDP has been approved and marketed as a commercial drug.