PubMed Health⌕ Search

Biomedical subjects

W A Watson

Publications and source records attributed to W A Watson.

At least 145 records · Page 8Linked to original sources

Properties of substituted 2-trifluoromethylbenzimidazoles as uncouplers of oxidative phosphorylation.

1. The activity of 25 substituted 2-trifluoromethylbenzimidazoles in uncoupling oxidative phosphorylation by rat-liver mitochondria has been compared. 2. For halogen- or mixed-halogen- and alkyl-substituted analogues, uncoupling activity was proportional to the acidity of the imidazole -NH group. Tetrachloro-2-trifluoromethylbenzimidazole was the most active (50% uncoupling of oxidative phosphorylation at 7.9x10(-8)m, pK5.04). Nitro-substituted analogues were less active than predicted from pK considerations or from partition-coefficient measurements. 3. Introduction of an -NH(2) or -CO(2)H substitutent caused a loss of uncoupling activity, as did alkylation at position 1 of the imidazole ring. 4. Benzimidazoles active as uncouplers stimulated mitochondrial adenosine triphosphatase but not all stimulated the oxidation of succinate in the absence of a phosphate acceptor. 5. 4,5-Dichloro-2-trifluoromethylbenzimidazole inhibited the succinate-oxidase system at about the same concentration required for uncoupling (0.52mum for 50% inhibition of both activities) and the site of this inhibition appears to lie between succinate dehydrogenase and cytochrome b.

Animals↗

Recovery of cyclic antidepressants with gastric lavage.

The role of lavage fluid volume in recovery of cyclic antidepressant with gastric lavage was determined in 13 patients treated for moderate to severe cyclic antidepressant intoxication. An orogastric tube was placed, gastric contents aspirated, and gastric lavage performed with 60 to 180 mL aliquots of tap water or 0.9% NaCl for irrigation. A volume of 12.8 +/- 4.4 liters of lavage fluid was instilled, and 97.6 +/- 6.9% of this volume was recovered. The recovered aspirate and lavage fluid were inspected for the presence of particulate matter and saved in 4 to 5 liter collections. Determination of cyclic antidepressant and metabolite concentrations was performed using gas chromatography-mass spectrometry, and the amount of cyclic antidepressant recovered was calculated. The mean total amount recovered was 110 mg and ranged from 2.4 mg to 342 mg. Of the total amount recovered, 88% +/- 13% was recovered in the first 4 to 5 liters of lavage fluid. An estimate of the dose ingested was available in 7 patients, with 8.7% (0.4% to 21.7%) of the estimated dose recovered by lavage. There were no cases of significant drug recovery in clear lavage fluid. We conclude that if gastric lavage is undertaken in cyclic antidepressant intoxications, it should utilize 5 liters initially and then continue only if particulate matter is seen.

Adolescent↗