Ernest H Polak

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For certain odorants, the amplitude of the rat electro-olfactogram is reduced if the olfactory epithelium is treated with the lectin concanavalin A. When normal and cycloalkanes of one to ten carbon atoms are used as odorants at equimolar concentration, the maximum reduction in amplitude is found to correlate with the size of the stimulus molecule. This(More)
Carvone enantiomers (D and L optical isomers) have been shown to be discriminable by humans even though the odor qualities are quite similar. Our experiment is based on a finding (J. Steroid Biochem. Molec. Biol. 1991;39(4B):621) that Concanavalin A (ConA) applied to a frog olfactory epithelium preparation blocks cAMP transduction induced by D- but not by(More)
Human odor responses to alpha-ionone enantiomers were measured by psycho-physical methods. Surprisingly, subjects' relative sensitivities for these enantiomers were found to diverge widely, some subjects being much more sensitive to (+) than to (-) and vice versa. In 63 subjects the (+)/(-) threshold concentration ratio varied over 4 orders of magnitude.(More)
Rats were trained using an olfactometer to detect low concentrations of ethyl acetate (EA) or dimethyl disulphide vapor (DMDS). Concanavalin A (ConA) applied to the olfactory mucosa had no effect on ability of rats to detect low concentrations of EA but produced a marked deficit in detection in DMDS. DMDS detection performance returned to control levels 3(More)
The lectin concanavalin A (ConA) when applied to the olfactory mucosa (OM) of frog and rat, is reported to partially inhibit electro-olfactogram (EOG) responses to fatty acid odours. Control odours like isoamyl acetate were not affected. We have now studied in the frog whether this treatment affects the corresponding olfactory bulb (OB) response. The OB(More)
We have studied the effect of concanavalin A (Con A) on the rat electro-olfactogram response to several odorants. Each odorant was applied over a range of concentrations. For hydrophobic odorants whose response was affected by Con A, the diminution in response was maximal at odorant concentrations of about 1 microM in the olfactory mucus. The (odour)(More)
Odor similarity to the odor of 4-mercapto-4-methyl-2-pentanone (I) was measured on eight rats by generalization of a conditioned avoidance response tocis- andtrans-8-mercapto-p-menthan-3-one (II and III), 3-mercapto-3-methyl-2-pentanone (V), andt-amyl mercaptan (VI). Previously, these odorants had been found to induce stress in rats in an open-field(More)
1. A rat olfactory preparation, suitable for biochemical studies in vitro on olfactory mechanisms, is described. 2. The effects of the impermeant chemical modification reagents mersalyl (a thiol reagent) and enzymatic iodination, on the amplitude of the electroolfactogram (EOG) responses elicited from rat olfactory mucosa by pulses of odorant vapours was(More)
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