Fig. 2.
Odor-induced changes in calcium in fura-2-loaded human OSNs isolated from older subjects (>65 years old). (a and b) show odor responses in two cells. Red and blue points display fura-2 ratio in different cells. Fura-2 ratio was measured in the apical end of the dendrite (squares) and the cell body (diamonds). In panel a the cell whose fura-2 ratio is displayed in red showed increases in intracellular calcium when stimulated with odor mixture B2. The same cell responded to A with a decrease in calcium (panel b). (c) Example of an OSN that responded with increases in calcium when stimulated with different odor mixtures. A1=PEA, hedione, geraniol; A2= citralva, citronellal, A3= eugenol, menthone, B1= lyral, lillial, B2= triethylamine, isovaleric acid, phenylethyl-amine, B3= ethyl-vanillin, R’s= Ringer’s solution. The criterion for judging whether the cell responded to an odor was a change in the ratio more than two standard deviations.