Corticosterone responses, hurdle-jump acquisition, and the effects of dexamethasone using classical conditioning of fear

Coover, Gary D.; Sutton, Betty R.; Welle, Stephen; Hart, Robert P.

doi:10.1016/0018-506x(78)90032-6

Cited by 22 publications

(9 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, in adult Norway rats, shock-induced defensive freezing and crouching postures (Blanchard & Blanchard, 1969;Fanselow & Bolles, 1979), which are behavioral indices of fear in animals (Ratner, 1967) are reported to occur more frequently as the intensity of electric foot shock increases. Adrenal corticosterone secretion also increases positively as a function of stressor intensity (Coover, Sutton, Welle, & Hart, 1978). By having the capacity…”

mentioning

confidence: 98%

Development of stress‐induced responses in preweanling rats

Takahashi

Turner

Kalin

1991

Developmental Psychobiology

View full text Add to dashboard Cite

This study examined in postnatal Days 7, 14, and 21 male rats the effects of social isolation and social isolation with administration of brief foot shocks on the development of stress-induced behavioral and pituitary-adrenal hormone responses. Day 21 rats appeared similar to adult rats in their repsonses to the two test conditions. That is, exposure to either isolation or to shock increased both pituitary-adrenal hormone secretion and tail-flick latencies but only administration of shock potentiated freezing and ultrasonic vocalizations. Younger rats differed from Day 21 rats in their responses to the two test conditions. In both tests, Day 7 rats produced the highest number of ultrasounds, which may be due to a significant decrease in body temperature. In contrast, in Day 14 pups, exposure to shock significantly reduced isolation-induced ultrasonic vocalizations. Additional age-dependent differences were found in the analgesic responses of Days 7 and 14 rats. Day 7 rats exposed to stress became consistently hyperalgesic whereas Day 14 rats showed only a short-lasting analgesic response. Although in Days 7 and 14 rats exposure to the two stress conditions produced significant elevations in pituitary-adrenal hormone concentrations, plasma levels were lower than those measured in Day 21 rats. To summarize, preweanling rats exhibit varied age-dependent responses when exposed to different stress environments.

show abstract

mentioning

confidence: 98%

Development of stress‐induced responses in preweanling rats

Takahashi

Turner

Kalin

1991

Developmental Psychobiology

View full text Add to dashboard Cite

show abstract

“…The necessity for the inclusion of such an additional step in the normal procedures is surprising because there is a relatively large literature reporting successful escape-from-fear learning without such a requirement. These studies have been conducted in a number of laboratories with different experimenters, with different strains and sex of rats, and with differences in a number of specific details of apparatus and procedure (e.g., Brown & Jacobs, 1949;Coover, Sutton, Welle, & Hart, 1978;Daly, This research was supported in part by Grant MH-29232 from the National Institute of Mental Health. The authors are indebted to Stephen E. Dieter, Michael J. Grelle, and Teresa Owens Smith for aid in the collection and analysis of the data.…”

mentioning

confidence: 99%

Escape-from-fear performance as affected by handling method and an additional CS-shock treatment

McAllister

Hampton

et al. 1980

Animal Learning & Behavior

View full text Add to dashboard Cite

Experiment 1 demonstrated that hurdle-jumping, escape-from-fear (EFF) performance was affected deleteriously when the handling of the rats was by the tail rather than the body and was facilitated by the administration, just prior to EFF training, of one additional CS-shock pairing along with the opportunity to jump the hurdle. Additional experiments elucidated the basis for the effect of these two variables. Experiment 2 indicated that tail handling degraded performance by decreasing reinforcement. In Experiment 3, the facilitatory effect of the extra CS-shock treatment was found to result from the occurrence of a response at the termination of the pairing and not from the CS-shock pairing per se.In a typical escape-from-fear (EFF) task, classical fear-conditioning trials (CS-shock) are administered in one side of a two-compartment apparatus. Later, in the absence of shock, subjects are allowed to jump a hurdle to an adjacent safe compartment and, thereby, to escape the fear-eliciting CS and situational cues in the shock compartment. Theoretically, the learning of the instrumental hurdle-jumping response is motivated by these two sources of fear and is reinforced by the reduction of this fear following the response.Recently, Crawford, Masterson, and Wilson (1977) have reported difficulty in consistently obtaining such instrumental learning based either on fear of the CS alone or on fear of both the CS and situational cues. In order to obtain learning, they found it necessary to administer not only the classicalfear-conditioning trials but also an additional such trial, along with the opportunity to jump the hurdle, just prior to regular hurdle-jumping training. The necessity for the inclusion of such an additional step in the normal procedures is surprising because there is a relatively large literature reporting successful escape-from-fear learning without such a requirement. These studies have been conducted in a number of laboratories with different experimenters, with different strains and sex of rats, and with differences in a number of specific details of apparatus and procedure (e.g., Brown & Jacobs,

show abstract

“…We expected a positive incentive effect of pituitary-adrenal inhibition, without undue direct effects of the additional dehydration and hyperglycemia produced by the consumption of the concentrated sugar solution. After all, even feeding deprived rats food mash without water being available, which should have dehydrating consequences, decreases corticosterone levels for up to 40 min (Levine & Coover, 1976), and hyperglycemia does occur within 10 min of initiation of food mash consumption (Coover, Welle, & Hart, 1978). The effect of consumption of concentrated sucrose solution must be due to dehydration or hyperglycemia that is extreme and acute.…”

mentioning

confidence: 99%

Plasma corticosterone elevations in rats in response to consumption of concentrated sugar solutions.

Hart¹,

Coover²,

Shnerson³

et al. 1980

Journal of Comparative and Physiological Psychology

Self Cite

View full text Add to dashboard Cite

The results of three experiments indicated that male hooded rats exhibit marked corticosterone elevations when they freely consume .740 mol/1 (23.2% w/w) sucrose in tap water while nondeprived or .298 mol/1 (9.8% w/w) sucrose when deprived of water for 36 hr. The magnitude of the corticosterone elevation was increased by lengthening the duration of prior water deprivation (2, 24, or 48 hr) and by raising the sucrose solution concentration (.189, .298, or .470 mol/1). Free ingestion of tap water following sucrose consumption accelerated the decline from peak level of corticosterone during the period 60-120 min following the onset of sucrose consumption Glucose (.470 or 1.166 mol/1) consumption by 36-hr water-deprived rats also elevated corticosterone levels, but less effectively than equimolar sucrose. These data suggest strongly that the pituitary-adrenal system is activated by rapid, acute dehydration. The effect is surprising, considering the minimal effects of water deprivation per se on corticosterone levels and the interpretation of increased pituitary-adrenal activity as a sign of psychological stress.

show abstract

Corticosterone responses, hurdle-jump acquisition, and the effects of dexamethasone using classical conditioning of fear

Cited by 22 publications

References 16 publications

Development of stress‐induced responses in preweanling rats

Development of stress‐induced responses in preweanling rats

Escape-from-fear performance as affected by handling method and an additional CS-shock treatment

Plasma corticosterone elevations in rats in response to consumption of concentrated sugar solutions.

Contact Info

Product

Resources

About