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Journal ArticleDOI

The effects of ACTH, adrenalectomy and dexamethasone on the acquisition of an avoidance response in rats.

TL;DR: The action of ACTH on avoidance conditioning is clearly extra-adrenal, but ACTH is not essential to normal performance, at least when high levels of glucocorticoids are present.
About: This article is published in Physiology & Behavior.The article was published on 1970-08-01. It has received 75 citations till now. The article focuses on the topics: ACTH inhibitor & Avoidance response.
Citations
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Journal ArticleDOI
TL;DR: This work presents a meta-anatomy of the adrenal gland and its role in the development and management of disease and urges further investigation into the role of “cell reprograming” and “reconcretization” in the course of disease progression.

822 citations

Book ChapterDOI
01 Jan 1977
TL;DR: The pituitary—adrenal system plays an essential role in homeostatic functions and the brain as a target for these hormones has been paid little attention.
Abstract: The pituitary—adrenal system plays an essential role in homeostatic functions Numerous aspects of stress-induced pituitary—adrenal activation in relation to peripheral mechanisms of adaptation have been studied since Selye’s first observations on the general adaptation syndrome some 40 years ago (Selye, 1950) Little attention, however, has been paid to the brain as a target for these hormones Clinical observations frequently commented on psychological changes in addition to electrophysiological alterations in hyper- as well as hypocorticism (Cleghorn, 1957; Von Zerssen, 1976) Many a laboratory experiment during the last decade, however, disclosed the implication of a number of pituitary and hypothalamic hormonal peptides on various brain functions The importance of these entities was revealed by observations on behavioral disturbances following extirpation of the pituitary gland in rats (de Wied, 1969); in animals with hereditary diabetes insipidus, which lack the ability to synthesize vasopressin (de Wied et al, 1975a); or in rats in which the action of vasopressin in the brain is neutralized by intraventricular administration of specific vasopressin antiserum (van Wimersma Greidanus et al, 1975a)

180 citations

Journal ArticleDOI
TL;DR: The present study demonstrates that, when the increase of corticosterone in infancy is moderate, the adult rats show reduced anxiety, improved learning and a better coping strategy to deal with stressful situations.

144 citations

Journal ArticleDOI
TL;DR: An increase in response vigour on the first day of extinction, compared with acquisition asymptote, was observed in all placebo conditions; ACTH 1–24 and ACTH 4–10 reduced themagnitude of this effect;ACTH 4-10 (7-D-Phe) increased the magnitude of thiseffect.

143 citations

Journal ArticleDOI
TL;DR: The data indicate that CRF can affect behavior via a direct action on the central nervous system, and the question remains whether this activity is an intrinsic property of CRF, or mediated by the release of hormones or neuropeptides.
Abstract: In order to elucidate the involvement of the 41 amino-acid residue corticotropin-releasing factor (CRF) in the modulation of brain functioning, the behavioral profile of the releasing hormone was determined using tests for spontaneous behavior, grooming, active and passive avoidance behavior. Intracerebroventricular (ICV) administration of CRF in a dose that does not stimulate the pituitary-adrenal axis, resulted in an activation of open-field behavior, as measured by ambulation and rearing activities. Also grooming activity was significantly enhanced after central application of CRF. In hypophysectomized rats, which show an impaired shuttle-box avoidance acquisition, CRF restored acquisition for the duration of the treatment. Paradoxically, extinction of pole-jumping active avoidance behavior of intact rats was facilitated by the releasing factor, even in adrenalectomized animals. Passive avoidance behavior was affected bidirectional: higher doses of CRF (300 ng), given subcutaneously (SC), attenuated passive avoidance retention, probably via activation of the pituitary-adrenal system resulting in high corticosterone levels. Lower doses (30 ng), however, which were also given SC did not stimulate pituitary-adrenal activity, and facilitated retention of passive avoidance behavior. Central administration of CRF in very low doses (30 pg) had the same effect as higher doses of CRF given SC, i.e., inhibition of passive avoidance retention. Taken together, the data indicate that CRF can affect behavior via a direct action on the central nervous system. The question remains whether this activity is an intrinsic property of CRF, or mediated by the release of hormones or neuropeptides.

112 citations

References
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Journal ArticleDOI
TL;DR: A 100-fold increase in sensitivity has now been achieved by using tritiated steroids in place of 14C-labeled steroids, by utilizing the CBG's of species other than man, and by using adsorption in Place of dialysis or gel filtration.
Abstract: A method utilizing the steroid-binding properties of corticosteroid-binding globulin (CBG, transcortin) was described in 1963 for the routine determination of corticoids in 1 ml of plasma (J Clin Endocr 23: 293, 1963) and later modified to reduce the time required (J Clin Endocr 24: 919, 1964). A 100-fold increase in sensitivity has now been achieved by using tritiated steroids in place of 14C-labeled steroids, by utilizing the CBG's of species other than man, and by using adsorption in place of dialysis or gel filtration. The use of several insoluble adsorbing agents (Fuller's earth, Florisil, coated charcoal) to separate protein-bound and unbound steroids was investigated and their effects on specificity were studied. The use of these techniques in plasma, urine and cerebrospinal fluid was vindicated. With these methods, cortisol can be measured routinely in 0.01 ml of plasma or 0.1 ml of cerebrospinal fluid, and progesterone in 0.3 ml of plasma. Compound S (11-desoxycortisol), corticosterone, ...

2,059 citations

Journal ArticleDOI
D. de Wied1, B. Bohus1
24 Dec 1966-Nature
TL;DR: It is found that the rapid extinction of a CAR which occurs after posterior lobectomy or hypophysectomy can be prevented by treatment with ACTH, melanocyte stimulating hormone (α-MSH) or lysine vasopressin given during the extinction period.
Abstract: ATTENTION has recently been focused on the effect of peptides on conditioned avoidance behaviour. It has been shown that adrenocorticotrophic hormone (ACTH) administered during avoidance learning results in a delay of extinction of a conditioned avoidance response (CAR)1,2. We found that the rapid extinction of a CAR which occurs after posterior lobectomy or hypophysectomy can be prevented by treatment with ACTH, melanocyte stimulating hormone (α-MSH) or lysine vasopressin given during the extinction period3. Our observations indicate that the effect of ACTH which results in a delay of extinction of the CAR is located in the N-terminal part of the peptide, presumably within the first ten amino-acids4,5. The effect of lysine vasopressin or pitressin (posterior pituitary extract) administered during the extinction period appeared to be similar to that of ACTH and related peptides3. Accordingly, it was considered of interest to investigate whether the effect of vasopressin and of an ACTH-like peptide on extinction of the CAR involves the same mechanisms despite the structural difference of these two peptides.

249 citations

Journal ArticleDOI
D. de Wied1
TL;DR: ACTH, administered during extinction, delays extinction of an avoidance response in rats and results were interpreted to indicate that the active part of ACTH in this respect is located in the N-terminal part of the molecule, presumably in the first 10 amino acids.
Abstract: SummaryACTH, administered during extinction, delays extinction of an avoidance response in rats. To study structure activity relationships, the rate of extinction of an avoidance response performed in a shuttle-box and a pole jumping situation, was investigated in rats treated during the extinction period with ACTH (A3 peptide), synthetic ACTH β 1-24, β-MSH, α-MSH, ACTH 1-10, ACTH 5-10, and ACTH 11-24, administered as long acting zinc phosphate preparations. Zinc phosphate complex and protamine zinc insulin (PZI) were used as placebo control substances. It appeared that ACTH and related peptides significantly delayed the rate of extinction of the avoidance response. Full activity was obtained with ACTH 1-10 peptide while ACTH 5-10 was less active. ACTH 11-24 and PZI were without effect. These results were interpreted to indicate that the active part of ACTH in this respect is located in the N-terminal part of the molecule, presumably in the first 10 amino acids.

248 citations

Journal ArticleDOI
TL;DR: Adenohypophysectomized rats were subjected to an avoidance learning procedure and only 6 of 21 rats achieved the conditioning criterion against 14 of 18 sham-operated controls.
Abstract: Adenohypophysectomized rats were subjected to an avoidance learning procedure. Only 6 of 21 adenohypophysectomized rats achieved the conditioning criterion against 14 of 18 sham-operated controls. ...

188 citations