Corticosterone was the first biologically active hormone to be isolated from adrenal gland extracts (1, 2). Although contributing little to the body pool of adrenocortical steroids in man, it is one of the major adrenocortical secretory products in some animals, e.g., rodents (3). In man the major glucocorticosteroid is cortisol and the major mineralocorticosteroid is probably aldosterone; neve...

Corticosterone has received considerable attention as the principal hormonal mediator of allostasis or physiological stress in wild animals. More recently, it has also been implicated in the regulation of parental care in breeding birds, particularly with respect to individual variation in foraging behavior and provisioning effort. There is also evidence that prolactin can work either inversely...

introduction: the role of different parts of the extended amygdala in metabolic signs of stress is not well understood. in the present study, we decided to evaluate the impact of the shell part of nucleus accumbens (nac) on metabolic disturbance induced by electro foot shock stress using transient inactivation method in the rat.  methods: male wistar rats (w: 230-250 g) were canuulated unilater...

Glucocorticoids are widely administered for the treatment of various disorders, although their long-term use results in adverse effects associated with glucocorticoid excess. We investigated the pathophysiological roles of glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs) in the cardiac changes induced by exogenous corticosterone in rats. Corticosterone or vehicle was injecte...

Repeatability of physiological response variables, such as the stress hormone corticosterone, across numerous sampling occasions is an important assumption for their use as predictors of behaviour, reproduction and fitness in animals. Very few studies have actually tested this assumption in free-living animals under uncontrolled natural conditions. Non-invasive urine sampling and standard captu...

Repeated stress induces corticosterone release. However, it is not clear that stress results in further elevation of corticosterone levels, and the roles of released corticosterone to aggravate stress-related symptoms are also not clear. This study investigated whether neuronal modulation was induced in the amygdala after two kinds of stress, that is, such as electric shock and corticosterone i...

Plasma levels of corticosterone are often used as a measure of "stress" in wild animal populations. However, we lack conclusive evidence that different stress levels reflect different survival probabilities between populations. Galápagos marine iguanas offer an ideal test case because island populations are affected differently by recurring El Niño famine events, and population-level survival c...

The present study examined the feasibility of measuring the steroid hormone corticosterone in fecal extracts of epaulette sharks, Hemiscyllium ocellatum. Six immature, captive-raised epaulette sharks (four females and two males) were obtained from two different zoos and were maintained in a closed-system, 530-liter aquarium. After a one-month adaptation, fecal samples were collected daily from ...

An earlier study of free-living male dark-eyed juncos found an increase in plasma corticosterone (B) in response to experimental elevation of plasma testosterone (T) (E. D. Ketterson et al., 1991, Horm. Behav. 25, 489-503). To investigate whether the increase was caused by enhanced secretion of corticosterone or by a slower clearance rate, or both, we exposed 52 captive yearling male dark-eyed ...

The relationship between glucocorticoids (GCs) and memory is complex, in that memory impairments can occur in response to manipulations that either increase or decrease GC levels. We investigated this issue by assessing the relationship between serum corticosterone (the primary rodent GC) and memory in rats trained in the radial arm water maze, a hippocampus-dependent spatial memory task. Each ...