DL-Kynurenine is a racemic mixture of D-kynurenine and L-kynurenine. Kynurenine is the precursor of kynurenic acid, an endogenous antagonist of the glycine site of the NMDA (N-methyl-D-aspartate) receptor. Kynurenine has been identified as an endogenous ligand of the aryl hydrocarbon receptor (AhR), a receptor known to be activated by various environmental toxicants, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

Oxfenicine is a CPT-1b-specific inhibitor. It must be transaminated to its active form, 4-hydroxyphenyl-glyoxylate, which is competitive with carnitine, preventing the formation of acylcarnitine. Because CPT-1b shows the highest sensitivity to 4-hydroxyphenyl-glyoxylate, inhibition of fatty acid oxidation by oxfenicine takes place selectively in those tissues that express this CPT isoform. It may be effective for treating noninsulin-dependent diabetes mellitus which is characterized by elevated fatty acid levels and obesity. In 1980 it was also tested in preclinical models of angina pectoris and ischemia.

3′,4′-Dihydroxyflavonol (diOHF) is an antioxidant compound capable of preserving Nitric Oxide activity in the presence of reactive oxygen species, and suppressing NADPH oxidase-dependent superoxide accumulation. It has generated interest as a potential therapeutic compound, and preliminary investigations have been conducted ina number animal and in vitro models for ischemic conditions and diabetes.

1-(5-iodonaphthalene-1-sulfonyl)-1H-hexahydro-1,4-diazepine (ML-7) is an inhibitor of myosin light chain kinase (MLCK). It is widely used to study MLCK signaling both in vitro and in vivo.

LY-255283 is a tetrazole derivative that acts as the competitive antagonist of the Leukotriene B4 (LTB4) receptor 2 (BLT2). LY255283 shows potent inhibition of LTB4 binding to human neutrophils and of LTB4-induced aggregation of guinea-pig neutrophils. In guinea-pigs, this compound also suppressed both specific binding of LTB4 to lung membrane and LTB4-induced contraction of lung parenchyma. Intravenous and oral administration of LY255283 dose-dependently reduced airway obstruction in guinea-pigs induced by LTB4, but not by histamine and U- 46619. Antigen-induced lung eosinophilia in rats was inhibited by orally administered LY255283. LY255283 exhibited the ability to suppress the shock induced by endotoxin and splanchnic artery occlusion in rats. LY255283 (bolus i.v. and subsequent infusion) attenuated endotoxin-induced adult respira¬tory distress syndrome in the pig model. LY255283 is used in leukotriene receptor research along with other selective leukotriene receptor agonists and antagonist to identify and differentiate the physiological and cell signaling effects of the leukotriene B4 receptor on processes such as paclitaxel resistance in MCF-7/DOX breast cancer cells, monocyte-derived dendritic cell chemotaxis, and 5-lipoxygenase activity and interleukin-8 production in human neutrophils.

Pratol is an O-methylated flavone that can be found in Trifolium pratense and Caragana microphylla. It has been found to induce melanogenesis and stimulate tyrosinase activity in melanoma cells and may have potential as a tanning agent in the cosmetics industry. Pratol has also been investigated for potential anti-ischemic effects.

GR79236 is an adenosine A1 receptor agonist, which possesses cardiovascular and antilipolytic properties. GR79236 was studied in model animals for the treatment of diabetic ketoacidosis and in patients for pain relief. However, these studies were discontinued. In addition, analgesic efficacy of GR79236 was investigated in the dental pain model. Nevertheless, there was no evidence of efficacy of GR79236. A higher dose of GR79236 might have been effective or that was suggested, that intravenous administration of that drug did not achieve appropriate concentrations in the brain or peripheral nerves.

The cyclopentenone prostaglandin A1 (PGA1) is considered as an antitumor agent. Its action basis on two distinct mechanisms: direct cytostatic/cytotoxic effects on cancer cells. In addition, the second one is the inhibitory activity of a tumor-associated enzymatic function (i.e., telomerase) that is responsible for cancer cell immortality. In addition, was shown, that PGA1 triggers apoptosis by a process that entails the specific activation of H- and N-Ras isoforms, leading to caspase activation. Rodent models with focal cerebral ischemia have shown that PGA1 has the neuroprotective potential.

Adenosine monophosphate (AMP) is a nucleotide, consisting of a phosphate group, the sugar ribose, and the nucleobase adenine. AMP is an activator of several enzymes in the tissues. In the glycolytic pathway, the enzyme phosphofructokinase is inhibited by ATP but the inhibition is reversed by AMP, the deciding factor for the reaction being the ratio between ATP and AMP. In medicine, AMP is used mainly as an alternative to adenosine for treatment of ischemia and as a tool compound to measure hyperresponsiveness of airways.

Isorhynchophylline is a plant alkaloid isolated from Uncaria species with therapeutic potential for cardiovascular and central nervous system diseases. The antihypertensive effect of isorhynchophylline was firstly observed in 1989, which was strongly linked to the traditional use of Uncaria species (Gouteng in Chinese). Isorhynchophylline and rhynchophylline were the main hypotensive constituents in Uncaria rhynchophylla. In rat isolated mesenteric arteries and tail artery, isorhynchophylline inhibited the increased infusion pressure induced by high K+ and norepinephrine in a concentration-dependent manner. The potency of isorhynchophylline and rhynchophylline was similar in mesenteric arteries, but in the tail artery, the effect of isorhynchophylline on high K+ induced infusion pressure increase was stronger than that of rhynchophylline, and there was a similar trend in the contractile response induced by norepinephrine. Isorhynchophylline also inhibited the hypertensive effect of angiotensin II. The results indicate that in small blood vessels of rat, isorhynchophylline can directly inhibit the contractile responses induced by several agonists. In vivo, ouabain and CaCl2 were used to establish experimental arrhythmic models in guinea pigs and rats. In vitro, the whole-cell patch-clamp technique was used to study the effect of isorhynchophylline on action potential duration and calcium channels in acutely isolated guinea pig and rat cardiomyocytes. Isorhynchophylline, infusion 0–16 mg/kg at a constant rate, dose-dependently decreased heart rate, prolonged sinus node recovery time, and PR, AH, HV intervals. Isorhynchophylline significantly inhibited the heart rate and atrioventricular conduction. These inhibitory effects of isorhynchophylline were partially antagonized by isoprenaline, but not by atropine. Isorhynchophylline inhibited the automaticity and contractile force of isolated guinea pig atrium in a concentration-dependent manner. Isorhynchophylline significantly depressed adrenaline-induced automaticity, and prolonged functional refractory period and decreased excitability. Furthermore, 10 μmol/L of isorhynchophylline reduced the effect of ouabain on the contractile force in the left atrium and significantly inhibited the response to paired stimulation. In anesthetized dogs, isorhynchophylline markedly reduced the tension-time index which indicated myocardial oxygen consumption. The result indicates that the decrease of myocardial oxygen consumption by isorhynchophylline would protect the heart against ischemia induced by hypertension. Isorhynchophylline showed a mild central depressive effect in mice. Isorhynchophylline significantly decreased locomotor activity after oral administration to mice. The depression of locomotor activity upon administration of the alkaloid appears to be due to mediating of the central dopaminergic system. Isorhynchophylline dose-dependently inhibited 5-hydroxytryptamine (5-HT)2A receptor-mediated head-twitch but not 5-HT1A receptor-mediated head-weaving responses evoked by 5-methoxy-N, N-dimethyltryptamine. Isorhynchophylline attenuated the in vitro ischemia-induced neuronal damage in a dose-dependent manner. Isorhynchophylline protects against glutamate-induced neuronal death in cultured cerebellar granule cells by inhibition of Ca2+ influx. Pretreatment with isorhynchophylline significantly elevated cell viability, decreased the levels of intracellular reactive oxygen species and malondialdehyde, increased the level of glutathione, and stabilized mitochondrial membrane potential in β- amyloid(25–35)-induced neurotoxicity in rat pheochromocytoma cells. In unthoracotomized dogs, isorhynchophylline (5 mg/kg, iv) reduced the mean arterial pressure but did not affect renal blood flow. Isorhynchophylline did not block nictitating membrane contraction induced by stimulating collum sympathetic nerve and did not decrease blood pressure after injected in the cerebral ventricle.