1. The contribution of taste bud populations to bitter avoidance in mouse strains differentially sensitive to sucrose octa-acetate and quinine.
John D Boughter Jr, Steven J St John. Chem Senses. 2004 Nov; 29(9): 775-87. DOI: 10.1093/chemse/bjh082. PMID: 15574813.
Mice of the SWR/J (SW) strain avoid orally delivered sucrose octa-acetate (SOA), whereas the mice of the C3HeB/FeJ (C3) strain are insensitive to SOA. Mice of both strains and of a congenic strain (C3.SW) that shares more than 99% of the C3 genome, were tested in a taste-salient brief-access taste test for responses to SOA and quinine hydrochloride, before and after transection of the glossopharyngeal or chorda tympani nerve, or sham surgery. Prior to surgery, congenic SOA tasters (C3.SW(T)) were phenotypically identical to the SW strain in avoidance of SOA, but showed a greater reduction in sensitivity after nerve transection. For quinine avoidance, which is thought to be a polygenic trait, SW mice showed the greatest sensitivity to quinine, C3 the least and C3.SW(T) mice were different from both parental strains, showing intermediate sensitivity. Nerve transections had only a moderate effect on quinine sensitivity, suggesting that both anterior and posterior taste bud fields contribute to behavioral quinine avoidance. These findings are discussed with regard to the distribution in the oral cavity of putative taste receptors for quinine and SOA and the peripheral organization of bitter taste.
2. Nonaqueous titration of sulfates of quinine and quinidine using barium acetate.
H Abdine, N A Zakhari, S A Soliman. J Pharm Sci. 1976 Mar; 65(3): 424-7. DOI: 10.1002/jps.2600650327. PMID: 1263094.
A nonaqueous titrimetric method is proposed for determining the diastereomeric sulfates of quinine and quinidine. The sulfuric acid content of the alkaloid salts is precipitated, in the form of barium sulfate, with acetous barium acetate solution before the liberated alkaloid is titrated; the necessary calculations are provided. A favorable characteristic of the proposed procedure is the accuracy, speed, and ease of performance. The mean percent recoveries (p = 0.05) obtained with the proposed method for the sulfates of quinine and quinidine were 98.84 +/- 1.00 and 99.74 +/- 1.27, respectively, compared with 100.73 +/- 1.44 and 100.82 +/- 1.16, respectively, when the BP 1968 procedure was applied.
