Disease relevance of octanol

• The cytotoxic activities of several natural and semisynthetic anthracyclines against L1210 leukemia and two human colon tumor cells (Colon 4, HT 29) in vitro were examined after short (1 h) and long (7 days) incubation times and correlated with the water/octanol partition coefficients and the DNA-binding affinity of the compounds [1].
• A mechanism-based model for prediction of acute nitrile toxicity was developed using octanol-water partition coefficients (log P) and estimated rates of alpha-hydrogen atom abstraction as variables [2].
• Growth on octane alters the membrane lipid fatty acids of Pseudomonas oleovorans due to the induction of alkB and synthesis of octanol [3].
• Radiolabeled 2-nitroimidazoles have been used for imaging hypoxia, and the octanol/water partition coefficient (P) of these compounds appears to play a crucial role in their suitability for imaging [4].
• One set contains the inhibition concentration at 50% for 121 HIV-1 protease inhibitors, while the second set contains 12865 octanol/water partitioning coefficients (Log P) [5].

Psychiatry related information on octanol

• After correction for individual differences in protein binding, volume of distribution (Vd) of unbound drug was highly correlated with HPLC retention (r = 0.91), but not significantly related to octanol/buffer partition coefficient [6].
• The rapid brain entry of exendin-4, helped by its high lipophilicity as demonstrated by the octanol/buffer partition coefficient, was not dependent upon circumventricular organs and was not affected by food deprivation for 24 h [7].
• The results indicate that the grass is behaving as a two-compartment system: (1) a fast-exchanging surface adsorption site with a response time of hours and a capacity essentially independent of K(OA), the octanol-air partition coefficient and (2) a slow responding site with a response time of weeks, the capacity of which is related to K(OA) [8].

High impact information on octanol

• The gap junction blocker octanol attenuated the neuronal response, which suggests that the astrocytic-neuronal signaling is mediated through intercellular connections rather than synaptically [9].
• In contrast, gastric ADH has a high affinity for octanol, and 66% of this compound was metabolized during gastric absorption [10].
• Junctional conductance (gj) between hepatocyte pairs is reduced by exposure to octanol (0.1 mM) and by intracellular acidification [11].
• This effect was significantly eliminated in cells pretreated with a 1 mM dose of octanol, which inhibits gap junction-mediated intercellular communication, or in cells carrying a dominant negative connexin 43 vector [12].
• The free energy of salt-bridge formation in octanol is approximately -4 kcal/mol (1 cal = 4.184 J), which is equal to or slightly larger than the sum of the solvation energies of noninteracting pairs of charged side chains [13].

Chemical compound and disease context of octanol

• Because synchrony in some networks is mediated by gap junctions, we examined whether the gap junction blockers heptanol, octanol, carbenoxolone, and mefloquine suppress tremor in the mouse harmaline model, and performed an open-treatment clinical study of mefloquine for essential tremor [14].
• IMPLICATIONS: Lidocaine and octanol have different inhibitory effects on the function of tetrodotoxin-resistant Na(+) channels in rat dorsal root ganglion cells, as well as noncompetitive modes of action, as investigated by the whole-cell patch-clamp method, and therefore are likely to have different binding sites on the channel [15].
• The aim of the study was to investigate whether toxic fine chemical production can be improved using the solvent-tolerant Pseudomonas putida S12 in a two-liquid-phase system consisting of aqueous media and a water-immiscible octanol phase with production of 3-methylcatechol from toluene as the model conversion [16].
• Kinetic resolutions of octan-3-ol, 1-octen-3-ol and 1-octyn-3-ol by esterification with decanoic acid have been performed using Chromobacterium viscosum (CV) lipase [17].

Biological context of octanol

• We have shown previously that conductance of rat liver gap junctions is blocked by an affinity-purified polyclonal antibody generated against rat liver junctional membranes, is not affected by moderate transjunctional or transmembrane potentials, and is reversibly decreased by cytoplasmic acidification and perfusion with octanol [18].
• Consistent with this hypothesis, we found that pharmacologically uncoupling VZ cells with octanol decreases the percentage of VZ cells that enter S phase [19].
• The general anesthetic alcohols, butanol and octanol, further shifted lambda(max) of the PKCdelta C1B-bound sapintoxin-D in a concentration-dependent, saturable manner to approximately 415 nm, suggesting that alcohols interact at a discrete allosteric binding site [20].
• Na+/K(+)-ATPase IC50 values decrease linearly with increasing octanol/water partition coefficients (log-log plot) for a series of dimethylethylamine-containing drugs (i.e., chlorpromazine, amitriptyline, imipramine, doxepin, and diphenhydramine), emphasizing hydrophobicity in inhibition [21].
• Mitotic rates of GJIC in SIGC were comparable to values obtained in interphase cells partially uncoupled by 0.5 mM octanol [22].

Anatomical context of octanol

• The octanol/water partition coefficient for compound 10 was 2.09, suggesting that it has excellent physiochemical properties for crossing the blood brain barrier and penetrating brain tissue [23].
• Furthermore, since we did not observe any significant number of cytoplasmic bridges at the EM and Gj is sensitive to octanol, it is probable that blastomeres in the 2-cell and 32-cell embryos are in communication by gap junctions [24].
• As is the case for excess plasma membrane cholesterol, treating human fibroblasts with octanol, diglyceride, or ceramide stimulated the rapid inactivation of their hydroxymethylglutaryl-CoA reductase, presumably through an increase in the pool of endoplasmic reticulum cholesterol [25].
• Paradoxically, tracer molecules injected into the fiber mass were able to pass into the epithelium via a pathway that was not blocked by incubation at 4 degrees C or by treatment with octanol and which excluded large (approximately 10 kDa) molecular mass tracers [26].
• Consistent with the observed Cx43 immunostaining, octanol-sensitive in situ dye-coupling was observed between Leydig cells, between peritubular cells and between Sertoli cells, suggesting the occurrence of functional gap junctions in these cell types [27].

Associations of octanol with other chemical compounds

• The gap junction blockers octanol and 18alpha-glycyrrhetinic acid markedly reduced dye uptake, suggesting that uptake was mediated by opening of unapposed hemichannels [28].
• Conditions expected to close gap junction hemichannels (exposure to octanol and low intracellular pH) did not decrease ATP-induced Lucifer Yellow uptake, whereas conditions expected to increase hemichannel opening either did not affect ATP permeabilization (dibutyryl adenosine monophosphate) or decreased it (zero extracellular CA+2) [29].
• In vitro determination of high-performance liquid chromatography mobility, octanol/ water partitioning, cholesterol solubilizing capacity, and sensitivity to enzyme deconjugation by bacteria and cholylglycine-hydroxylase were performed [30].
• The octanol/saline partition coefficients of radioactive iron in solution with transferrin, nitrilotriacetic acid, or chloride were all less than 0.06 [31].
• The washout (15 min) led to a complete recovery of junctional currents after treatment with octanol; the action of halothane was irreversible [32].

Gene context of octanol

• The gap-junction inhibitor octanol reduced TGFbeta3-increased levels of bFGF in FS cells [33].
• CFTR activation by octanol requires phosphorylation by protein kinase-A (PKA) since it was prevented by H-89, a PKA inhibitor [34].
• This work examines the inter-relationship between the unbound drug fractions in blood and brain homogenate, passive membrane permeability, P-glycoprotein (Pgp) efflux ratio, and log octanol/water partition coefficients (cLogP) in determining the extent of central nervous system (CNS) penetration observed in vivo [35].
• The octanol/buffer partition coefficient of 0.232 showed that orexin A was highly lipophilic, whereas the value for orexin B was only 0.030 [36].
• In excised membrane patches, application of flufenamic acid or octanol to the extracellular surface of Cx50 hemichannels reduced single channel-open probability without altering the single-channel conductance, but application to the cytoplasmic surface had no effect on the channels [37].

Analytical, diagnostic and therapeutic context of octanol

• The additional hydroxyl group of 1,8 octan-diol is thereby forced to reside in a hydrophobic pocket, and isothermal titration calorimetry experiments indicate that this is accompanied by a standard free energy penalty of +21 kJ/mol with respect to octanol and +18 kJ/mol with respect to nonanol [38].
• Following disruption of gap junctional dye coupling by treatment with 1 mM octanol, microinjection of Lucifer yellow CH revealed the extent and distribution of follicle cell intercellular bridges to be confined to arrays of no more than eight cells/cluster, with many such independent clusters comprising the epithelium [39].
• The in vitro conversion of the lipophilic molecule [99mTc]-d,l-hexamethylpropyleneamine oxime [( 99mTc]-d,l-HM-PAO) to a hydrophilic form was studied in saline, plasma, and blood at 37 degrees C by paper chromatography and by octanol extraction [40].
• A technique is presented for the direct measurement of octanol-water partition coefficients by HPLC [41].
• Micellar electrokinetic chromatography (MEKC) was evaluated as a new technique for the rapid estimation of octanol-water partition coefficient (logKow) [42].

References