Relative inhibitory potency

FIGURE 4. Correlation between the relative inhibitory potencies of various drugs at high- and low-affinity [ H]MDA binding and between drug lipophilicities and inhibition potencies of [ H]MDA binding... 

Fig. 5. Structure and biological activities of Kiessling s initial carbohydrate-substituted polymers generated by ROMP. Relative inhibitory potency the saccharide residue concentration needed to inhibit the agglutination of red blood cells mediated by the protein concana-valin A... 

Diedrich, D. F., 7n Vitro Evaluation of Relative Inhibitory Potency of... 

Kj values, however, were in the nanomolar range, with the Kj for the maltohexaosyl acarbose, 33 nM for A. oryzae a-amylase, 37 nM for B. amyloliquefaciens a-amylase, 14nM for human salivary a-amylase and 7.0nM for porcine pancreatic a-amylase. These inhibition constants represented relative inhibitory potency over acarbose of 8200-, 351 -, 90- and 114-times, respectively for the four a-amylases.220d... 

FIGURE 57.8. Spectrum of log values of relative inhibitory potency (RIP) = 7i(AChE)/ i(NTE), where = himolecular rate constant of inhibition. As log(RIP) becomes more positive, cholinergic potential increases as log(RIP) becomes more negative, delayed neuropathic potential increases. CPMO-chlorpyrifos methyl oxon. DCV derivatives refer to symmetrical dialkyl-2,2-dichlorovinyl phosphate (dichlorvos) compounds. EOPF - ethyl n-octylphosphonofluoridate. Data from Kropp and Richardson (2003) Richardson (1992) and Wu and Casida (1996). 

In keeping with the concept of the RIP discussed under Relative Inhibitory Potency , above, inhibition of lymphocyte and/or platelet NTE and possibly erythrocyte LysoPC hydrolase should be used in conjunction with inhibition of erythrocyte AChE and plasma butyryl-cholinesterase (BChE) to assess the likelihood that an exposure to OP compounds would produce cholinergic and/ or delayed neuropathic effects. Erythrocyte AChE inhibition has long been used as a biomarker of exposure to conventional nerve agents or OP insecticides (Lotti, 1995 Wilson and Henderson, 1992). BChE can be sensitive to both conventional and DN agents, and its inhibition could thus serve as a general biomarker for OP agents (Kropp and Richardson, 2007 Van der Schans et al, 2008). 

Kropp, T.J., Richardson, R.J. (2003). Relative inhibitory potencies of chlorpyrifos oxon, chlorpyrifos methyl oxon, and mipafox for acetylcholinesterase versus neuropathy target esterase. J. Toxicol. Environ. Health Part A 66 1145-57. 

Relative inhibitory potencies (rIPs) of Oligosaccharide Inhibitors of MAG [32]... 

In a homologous series of OP compounds, increasing potency for AChE inhibition and cholinergic toxicity correlates with decreasing potency for NTE inhibition and OPIDN. The relative inhibitory potency (RIP) of an OP compound or its active metabolite for NTE versus AChE in vitro can be used as a convenient index of the probable neuropathic potential of the compound. A commonly used measure of inhibitory potency is the IC50, the concentration required to inhibit 50% of the enzyme activity under a standardized set of reaction conditions and time of incubation of the inhibitor with the enzyme preparation. A better measure of inhibitory potency is the bimolecular rate constant of inhibition, ki. When... 

TABLE 2. Influence of fluorine atoms on relative inhibitory potency... 

To select the antiserum best suited for detection of 3-Cys-A adducts in the presence of free acetaminophen, the relative inhibitory potencies of... 

To evaluate the amount of acetaminophen bound to proteins, utilizing the competitive A-B ELISA or PCFIA, inhibition by unknown samples was compared with an assay standard prepared by derivatizing protein with NAPQI. For some experiments, 3-(N-acetyl-L-cystein-S-yDacetaminophen was used as an assay standard, in which case, the values obtained were corrected for differences in the relative inhibitory potency of 3-(N-acetyl-L-cystein- yl)acetaminophen and 3-Cys-A protein adduct (120 fmol/well and 2300 finol/well, respectively) (14). After dialysis, unknown samples were diluted to a final concentration of approximately 4 / g protein/assay well, assayed in duplicate, and expressed as nmoles of 3-Cys-A per mg of protein. The ELISA and PCFIA were shown to have similar limits of detection (20 pmole/mg protein) and to recognize the same itope as demonstrated by similar relative inhibitory potencies for N-acetylcysteine-acetaminophen, acetaminophen-bound... 

NSAIDs can be classified on the basis of their COX inhibitory and selectivity properties. In general, most NSAIDs inhibit both COX-1 and COX-2 to some extent, but most are mainly COX-1-selective (e.g., aspirin, sulindac, indomethacin, ketoprofen, piroxicam) some are somewhat selective for COX-1 (e.g., ibuprofen, diclofenac, naproxen) others are slightly selective for COX-2 (etodolac, meloxicam) while NSAIDs like luntiracoxib, rofecoxib, and cele-coxib are clear selective inhibitors of COX-2 (Fig. 9.3). Clearly, knowing the relative inhibitory potencies of different NSAIDs for COX-1 and COX-2 would be useful in attempting to... 

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