ODOR DISCRIMINATION OF CAMP-INCREASING AND IP3-INCREASING ODORANTS ATHIGH-TEMPERATURE AND AT HIGH NACL CONCENTRATION IN TURTLE OLFACTORY SYSTEM

The ability of the turtle olfactory system to discriminate between var ious cAMP and IP3-increasing odorants at high temperature and at high NaCl concentration in the olfactory bulb was examined by the cross-ada ptation technique. The degrees of discrimination in high [Na+] solutio n were similar to those in normal Ringer's solution, suggesting that s electivities of receptors coupled with cAMP- and IP3-dependent pathway s are similar to those coupled with both cAMP- and IP3-independent pat hways. The mean values of the degree of discrimination among the IP3-i ncreasing odorants were higher than those among the cAMP increasing od orants at high temperature and at high [Na+] concentration. The degree s of discrimination among the IP3-increasing odorants at 40 degrees C were greater than those at 25 degrees C, while those among the cAMP-in creasing odorants at 40 degrees C were similar to those at 25 degrees C, suggesting that the features of the receptors of cAMP-increasing od orants are different from those which respond to IP3-increasing odoran ts.