TY - JOUR
T1 - Fear-potentiated startle response in mice
T2 - Genetic analysis of the C57BL/6J and DBA/2J intercross
AU - McCaughran, James A.
AU - Bell, James
AU - Hitzemann, Robert J.
N1 - Funding Information:
This research was supported by grants from the National Science Foundation (IBN9811426 to J.A.M.), Department of Veteran's Affairs (R.H.), United States Public Health Service (MH-51372 to R.H. and MH12318-02 to J.B.III)
PY - 2000/2
Y1 - 2000/2
N2 - The role of genetic factors in the fear-potentiated startle (FPS) response was examined in the inbred C57BL/6J (B6) and DBA/2J (D2) mouse strains. Mice in the D2 strain displayed a significant potentiation in the acoustic startle response (ASR) when presented with a visual condition stimulus (CS) previously paired with an aversive unconditioned stimulus (US). The maximal FPS response was observed following 20 conditioning trials but a near maximal response was noted following as few as five trials. Forty conditioning trials produced a significant reduction in the FPS response that may be related to overtraining. The FPS response in the B6 strain was significantly lower than the D2 strain, regardless of the number of conditioning trials. The contrasting FPS responses were not related to differences in auditory sensitivity known to exist between these strains. Analysis of a full Mendelian cross formed from the B6 and D2 strains found that the FPS response was a highly heritable trait, best described by a simple additive model of inheritance and with a broad-sense heritability of 0.46. The distribution of the FPS response in F2 hybrids formed from the intercross of the D2 and B6 strains was continuous which suggests a multigenic substrate. The light + noise and noise-alone trial types were highly correlated, but no association was detected between the baseline ASR amplitude and the FPS response. Mice from the phenotypic extremes of the F2 distribution displayed FPS responses that were more extreme than either of the progenitor strains. However, both baseline startle amplitude and the salience of auditory stimuli did not differ in these groups. The results of this study confirm an early report by Falls et al. (1997), and provide additional quantitative genetics information necessary for the eventual mapping of the chromosomal regions or genes associated with the FPS response in mice. (C) 2000 Elsevier Science Inc.
AB - The role of genetic factors in the fear-potentiated startle (FPS) response was examined in the inbred C57BL/6J (B6) and DBA/2J (D2) mouse strains. Mice in the D2 strain displayed a significant potentiation in the acoustic startle response (ASR) when presented with a visual condition stimulus (CS) previously paired with an aversive unconditioned stimulus (US). The maximal FPS response was observed following 20 conditioning trials but a near maximal response was noted following as few as five trials. Forty conditioning trials produced a significant reduction in the FPS response that may be related to overtraining. The FPS response in the B6 strain was significantly lower than the D2 strain, regardless of the number of conditioning trials. The contrasting FPS responses were not related to differences in auditory sensitivity known to exist between these strains. Analysis of a full Mendelian cross formed from the B6 and D2 strains found that the FPS response was a highly heritable trait, best described by a simple additive model of inheritance and with a broad-sense heritability of 0.46. The distribution of the FPS response in F2 hybrids formed from the intercross of the D2 and B6 strains was continuous which suggests a multigenic substrate. The light + noise and noise-alone trial types were highly correlated, but no association was detected between the baseline ASR amplitude and the FPS response. Mice from the phenotypic extremes of the F2 distribution displayed FPS responses that were more extreme than either of the progenitor strains. However, both baseline startle amplitude and the salience of auditory stimuli did not differ in these groups. The results of this study confirm an early report by Falls et al. (1997), and provide additional quantitative genetics information necessary for the eventual mapping of the chromosomal regions or genes associated with the FPS response in mice. (C) 2000 Elsevier Science Inc.
KW - C57BL/6J
KW - Conditioned fear
KW - DBA/2J
KW - Fear-potentiated startle
KW - Genetics
KW - Inbred mice
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U2 - 10.1016/S0091-3057(99)00216-6
DO - 10.1016/S0091-3057(99)00216-6
M3 - Article
C2 - 10672983
AN - SCOPUS:0033953006
SN - 0091-3057
VL - 65
SP - 301
EP - 312
JO - Pharmacology Biochemistry and Behavior
JF - Pharmacology Biochemistry and Behavior
IS - 2
ER -