The uptake of dibucaine into large unilamellar vesicles in response to proton gradients (delta pH; inside acidic) or membrane potentials (delta psi; inside negative) has been investigated. Dibucaine uptake in response to delta pH proceeds rapidly in a manner consistent with permeation of the neutral (deprotonated) form of the drug, reaching a Henderson-Hasselbach equilibrium where [dibucaine]in...

Serum cholinesterase activity and the dibucaine numbers have been determined by using a hydrogen peroxide electrode and the enzyme choline oxidase immobilized on a nylon net. The analysis procedure is extremely simple and very fast allowing 30 cholinesterase determinations per hour. Both cholinesterase activity and dibucaine number measurements could be performed in 5 min and by using serum sam...

In 1986, Ondrias et al. [Stud. Biophys. 115 (1986) 17] reported that dibucaine and other local anesthetics reduced the conductivity of membranes containing gramicidin ion channels. They attributed this behavior to a local anesthetic induced swelling of the membrane. Then in 1992, Bridal and Busath [Biochim. Biophys. Acta 1107 (1992) 31] re-examined this system using single channel measurements ...

The association o f the lipophilic tertiary amine and local anesthetic dibucaine with osmotically shocked chloroplasts o f Spinacia oleracea L. cv. Monatol was investigated. Dibucaine, known as an effective inhibitor o f thylakoid membrane energization and ATP synthesis, ex­ hibited three distinct binding classes with chloroplasts: partitioning in the lipid phase o f the membranes, electrostati...

Recurring waves of peri-infarct depolarizations (PIDs) propagate across gray matter in the hours and days following stroke, expanding the primary site of injury. Ischemic depolarization (termed anoxic depolarization or AD in live brain slices) is PID-like but immediately arises in the more metabolically compromised ischemic core. This causes dramatic neuronal and astrocyte swelling and dendriti...

diabetic nephropathy is common in mazandaran and a significant number of patients under chornic hemodialysis are diabetics. the present study was designed to study the prevalence and predisposing factors of diabetic nephropathy (dn) in mazandaran. methods: during a 20 months period from june 1993 through december 1994, 490 (350 female, 140 male) cases of non-insulin dependent diabetes mellitus ...

Cholinesterase activity was estimated in the serum of a Trinidadian female of Asian Indian descent. Her serum cholinesterase was pathologically low (0.17 U/ml) compared to the average reported for the population (10.59 ± 2.77 U/ml), and her dibucaine number could not be estimated. In a pedigree study her sister displayed similar enzyme activity and cholinesterase was 0.09 U/ml. Cholinesterase c...

The interaction of the local anesthetic dibucaine with the isolated toad skin and membrane models is described. The latter consisted of human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), large unilamellar vesicles (LUV) of dimyristoylphosphatidylcholine (DMPC) and phospholipid multilayers built-up of DMPC and dimyristoylphosphatidylethanolamine (DMPE), representative of ph...

This study aimed to illustrate the dose-response relationships of direct scavenging activity amide-based local anesthetics against multiple free radicals in vitro. We have demonstrated that amide-type selectively and directly scavenge some radicals. Three kinds were eliminated by all four examined. Mepivacaine, lidocaine, bupivacaine, dibucaine scavenged hydroxyl dose-dependent manners. Ascorby...

the solvatochromism of fluoresceine and its derivatives was studied in solvents of different hydrogen bond donor (hbd), hydrogen bond acceptor (hba), donor number (dn) and acceptor number (an) by their uv-vis spectra. results showed that position, intensity and shape of absorption bands change with type of solvent. these changes can be rationalized by solvatochromic parameters such as α, β, et ...