Correlation between choline acetyltransferase activity and learning ability in different mice strains and their offspring

The enzymes related to acetylcholine metabolism were investigated in several cortical regions of 3 inbred strains of mice (SEC, DBA and C57) differing in learning ability, and in their F1 offsprings. A higher choline acetyltransferase (ChAc) activity was found in the temporal lobe of mice with high learning ability (SEC and DBA) than in C57 mice which score poorly. The genetic behavioural analysis conducted on the F1 offsprings of these strains¹⁸ demonstrated that F1 hybrids of SEC and C57 crosses were able to reach the same high learning levels as the parental SEC strain. In contrast, the DBA × C57 offsprings performed as poorly as the C57 strain which had low levels of performance. We showed that ChAc activity in the temporal lobe of the SEC × C57 hybrids was close to that of the SEC strain and in the F1 offspring of DBA × C57 crosses, near the values of the parental line C57.It was suggested that these differences may constitute a neurochemical correlate of the differences in learning abilities of these mice strains.