Limits...
Influence of daily social stimulation on behavioral and physiological outcomes in an animal model of PTSD.

Seetharaman S, Fleshner M, Park CR, Diamond DM - Brain Behav (2016)

Bottom Line: We also found that social stimulation and psychosocial stress produced equivalent outcomes in some measures, including adrenal and heart hypertrophy, thymus atrophy, and a reduction in poststress corticosterone levels.It is notable that daily social stimulation normalized a subset, but not all, of the PTSD-like effects.We discuss our findings in the context of the literature demonstrating that social stimulation can counteract the adverse effects of traumatic stress on behavioral and physiological measures, as well as to produce its own stress-like outcomes.

View Article: PubMed Central - PubMed

Affiliation: Department of PsychologySt. Ambrose UniversityDavenportIowa52803; Center for Preclinical and Clinical Research on PTSDUniversity of South FloridaTampaFlorida33620.

ABSTRACT

Introduction: We have shown in previous work that acute episodes of predator exposure occurring in the context of chronic social instability produced PTSD-like sequelae in rats. Our animal model of PTSD contained two components: (1) acute trauma, immobilization of rats in close proximity to a cat twice in 10 days, and (2) chronic social instability, 31 days of randomized housing of cage cohorts. Here we tested the hypothesis that daily social stimulation would block the development of the PTSD-like sequelae.

Methods: Beginning 24 h after the first cat exposure, adult male rats were given our established PTSD model, alone or in conjunction with daily social stimulation, in which all rats within a group interacted in a large apparatus for 2 h each day for the final 30 days of the PTSD regimen. All behavioral, for example, anxiety, memory, startle testing, and physiological assessments, for example, body growth, organ weights, and corticosterone levels, took place following completion of the psychosocial stress period.

Results: Daily social stimulation blocked the expression of a subset of PTSD-like effects, including predator-based cued fear conditioning, enhanced startle response, heightened anxiety on the elevated plus maze and the stress-induced suppression of growth rate. We also found that social stimulation and psychosocial stress produced equivalent outcomes in some measures, including adrenal and heart hypertrophy, thymus atrophy, and a reduction in poststress corticosterone levels.

Conclusions: Daily exposure of rats to a highly social environment blocked the development of a subset of trauma-induced sequelae, particularly fear-related outcomes. It is notable that daily social stimulation normalized a subset, but not all, of the PTSD-like effects. We discuss our findings in the context of the literature demonstrating that social stimulation can counteract the adverse effects of traumatic stress on behavioral and physiological measures, as well as to produce its own stress-like outcomes.

No MeSH data available.


Related in: MedlinePlus

Timeline for psychosocial stress procedures and testing. Rats were exposed to the cat on Days 1 and 11. Beginning on Day 1, rats were also administered daily social instability, composed of pseudorandomized housing of each pair of rats in their home cages (brown arrow). Beginning on the day after the cat exposure (indicated by the white arrow within the brown arrow), rats in the social stimulation groups were brought to the laboratory and exposed to the social apparatus each day (Social) or they remained in their home cages (No Social). Social and stress manipulations terminated on Day 31, followed by the behavioral and physiological test battery, which began on Day 32.
© Copyright Policy - creativeCommonsBy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4834360&req=5

brb3458-fig-0001: Timeline for psychosocial stress procedures and testing. Rats were exposed to the cat on Days 1 and 11. Beginning on Day 1, rats were also administered daily social instability, composed of pseudorandomized housing of each pair of rats in their home cages (brown arrow). Beginning on the day after the cat exposure (indicated by the white arrow within the brown arrow), rats in the social stimulation groups were brought to the laboratory and exposed to the social apparatus each day (Social) or they remained in their home cages (No Social). Social and stress manipulations terminated on Day 31, followed by the behavioral and physiological test battery, which began on Day 32.

Mentions: An illustration of the timeline of all procedures is provided in Figure. 1.


Influence of daily social stimulation on behavioral and physiological outcomes in an animal model of PTSD.

Seetharaman S, Fleshner M, Park CR, Diamond DM - Brain Behav (2016)

Timeline for psychosocial stress procedures and testing. Rats were exposed to the cat on Days 1 and 11. Beginning on Day 1, rats were also administered daily social instability, composed of pseudorandomized housing of each pair of rats in their home cages (brown arrow). Beginning on the day after the cat exposure (indicated by the white arrow within the brown arrow), rats in the social stimulation groups were brought to the laboratory and exposed to the social apparatus each day (Social) or they remained in their home cages (No Social). Social and stress manipulations terminated on Day 31, followed by the behavioral and physiological test battery, which began on Day 32.
© Copyright Policy - creativeCommonsBy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4834360&req=5

brb3458-fig-0001: Timeline for psychosocial stress procedures and testing. Rats were exposed to the cat on Days 1 and 11. Beginning on Day 1, rats were also administered daily social instability, composed of pseudorandomized housing of each pair of rats in their home cages (brown arrow). Beginning on the day after the cat exposure (indicated by the white arrow within the brown arrow), rats in the social stimulation groups were brought to the laboratory and exposed to the social apparatus each day (Social) or they remained in their home cages (No Social). Social and stress manipulations terminated on Day 31, followed by the behavioral and physiological test battery, which began on Day 32.
Mentions: An illustration of the timeline of all procedures is provided in Figure. 1.

Bottom Line: We also found that social stimulation and psychosocial stress produced equivalent outcomes in some measures, including adrenal and heart hypertrophy, thymus atrophy, and a reduction in poststress corticosterone levels.It is notable that daily social stimulation normalized a subset, but not all, of the PTSD-like effects.We discuss our findings in the context of the literature demonstrating that social stimulation can counteract the adverse effects of traumatic stress on behavioral and physiological measures, as well as to produce its own stress-like outcomes.

View Article: PubMed Central - PubMed

Affiliation: Department of PsychologySt. Ambrose UniversityDavenportIowa52803; Center for Preclinical and Clinical Research on PTSDUniversity of South FloridaTampaFlorida33620.

ABSTRACT

Introduction: We have shown in previous work that acute episodes of predator exposure occurring in the context of chronic social instability produced PTSD-like sequelae in rats. Our animal model of PTSD contained two components: (1) acute trauma, immobilization of rats in close proximity to a cat twice in 10 days, and (2) chronic social instability, 31 days of randomized housing of cage cohorts. Here we tested the hypothesis that daily social stimulation would block the development of the PTSD-like sequelae.

Methods: Beginning 24 h after the first cat exposure, adult male rats were given our established PTSD model, alone or in conjunction with daily social stimulation, in which all rats within a group interacted in a large apparatus for 2 h each day for the final 30 days of the PTSD regimen. All behavioral, for example, anxiety, memory, startle testing, and physiological assessments, for example, body growth, organ weights, and corticosterone levels, took place following completion of the psychosocial stress period.

Results: Daily social stimulation blocked the expression of a subset of PTSD-like effects, including predator-based cued fear conditioning, enhanced startle response, heightened anxiety on the elevated plus maze and the stress-induced suppression of growth rate. We also found that social stimulation and psychosocial stress produced equivalent outcomes in some measures, including adrenal and heart hypertrophy, thymus atrophy, and a reduction in poststress corticosterone levels.

Conclusions: Daily exposure of rats to a highly social environment blocked the development of a subset of trauma-induced sequelae, particularly fear-related outcomes. It is notable that daily social stimulation normalized a subset, but not all, of the PTSD-like effects. We discuss our findings in the context of the literature demonstrating that social stimulation can counteract the adverse effects of traumatic stress on behavioral and physiological measures, as well as to produce its own stress-like outcomes.

No MeSH data available.


Related in: MedlinePlus