Strain-Dependent Changes in Acoustic Startle Response and its Plasticity Across Adolescence in Mice

Abstract

Acoustic startle response and its plasticity, e.g., habituation and prepulse inhibition (PPI), have been extensively investigated, being altered in several neuropsychiatric disorders. Yet, little is known about the expression of startle-related behaviors during adolescence, a critical phase in the development of a variety of major neuropsychiatric pathologies. The present study investigated for the first time startle behaviors across adolescence in male mice of the inbred strains C57BL/6J and DBA/2J. Pre-pubertal (4 weeks of age) mice displayed reduced startle reactivity and altered PPI compared to adult animals (8 weeks of age), but these effects were observed only in the C57BL/6J strain. Strain differences were also clearly detected for startle response, habituation, and PPI. All effects were modulated by the intensity of the pulse stimulus and were not confounded by differences in anxiety levels. Our data demonstrate that genetic factors and the early adolescent phase are critically important considerations in the design of mouse models of neuropsychiatric disturbances.

Vulnerability to omega-3 deprivation in a mouse model of NMDA receptor hypofunction

“…Sensorimotor gating can be affected by the testing age, where deficits are more pronounced in younger mice. 38, 39 In addition, genetic background can affect sensorimotor gating. 40 Our study used mice on a genetically-defined, F1 C57/129 background, and not the C57Bl/6J strain used in Federova et al .…”

“…40 Our study used mice on a genetically-defined, F1 C57/129 background, and not the C57Bl/6J strain used in Federova et al . 37, 38 It is interesting that the ω-3 supplemented diet produced impairments in the wild-type acoustic startle response. A possible explanation for this phenomenon is the effect of diet on ω-6 levels in the brain.…”

Genetic-Background Modulation of Core and Variable Autistic-Like Symptoms in Fmr1 Knock-Out Mice

“…The apparatus (SR-LAB, San Diego Instruments, San Diego, CA, USA) and procedures were previously described in detail [60], [61], [62], [63], [64]. Briefly, animals were acclimatized to the apparatus for 5 min.…”

“…The data obtained in the remaining trials were categorized into three main different subsets according to their relevance to distinct behavioral constructs [60], [61], [62], [63], [64]. First, startle reactivity was assessed by the reactivity scores obtained in the intermediate pulse-alone trials.…”

Linking Stress and Schizophrenia: A Focus on Prepulse Inhibition

“…Due to the small number of available studies, it is difficult to draw definite conclusion from this finding. Clearly, the rodent PPI response is strain, age and gender dependent (Palmer et al, 2000;Swerdlow et al, 2006;Pietropaolo & Crusio, 2009), and stress appears to differentially influence PPI across strains and sexes (Varty & Geyer, 1998;Faraday et al, 1999). Despite these limitations, it could be speculated that psychological stressors may have a higher ethological validity, which could produce more pronounced effects on PPI.…”