Proactive influence of a surgical stressor on locomotor activity, exploration and anxiety-related behaviour following acute footshock in the mouse.
The putative proactive influence of graded surgical stressors including intraventricular cannulation, sham surgery and no surgery on footshock-associated variations of locomotor activity, rearing and anxiogenic behaviour in the light-dark paradigm was evaluated among CD-1 mice. Neither sham surgery nor cannulation of the lateral ventricle altered baseline measures of locomotor activity or rearing relative to the performance of nonoperated control animals. Cannulation exacerbated the depressant influence of acute footshock on locomotor activity, while sham surgery mitigated the disruptive effect of the stressor on locomotor activity during the initial 15-min period of the test session. Footshock suppressed the vertical activity scores of mice regardless of surgical history. Only intraventricular cannulation reduced the baseline time in light scores of mice in the light-dark paradigm with repeated testing relative to animals in the sham surgery and no-surgery conditions. Baseline transition scores were not differentially affected by surgical history. Typically, transition scores were reduced on day 2 relative to day 1, but additional performance decrements were precluded on day 3. Footshock interacted with the surgical stressor of intraventricular cannulation in exaggerating reduced time in light relative to the performance of mice in the remaining surgical conditions. Transition frequency was not differentially influenced by the nature of the surgical stressor and subsequent exposure to footshock. The implications of these data for stressor-induced pathology are discussed.
Zacharko
R M
RM
Carleton University, Institute of Neuroscience, Unit for Behavioural Medicine and Pharmacology, Ottawa, Ontario, Canada. rzachark@ccs.carleton.ca
MacNeil
G
G
Mendella
P D
PD
Hebb
A L
AL
D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000503:physiopathology*; D001522:Behavior, Animal / Q000502:physiology; D002404:Catheterization / Q000523:psychology; D003624:Darkness; D004597:Electroshock; D007276:Injections, Intraventricular; D008029:Lighting; D008124:Locomotion / Q000502:physiology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009042:Motivation; D011183:Postoperative Complications / Q000503:physiopathology* / Q000523:psychology; D013315:Stress, Psychological / Q000503:physiopathology*