The hypophyseal–adrenocortical response to various different stressing procedures in ACTH-treated rats

1968 ◽  
Vol 46 (4) ◽  
pp. 567-571 ◽  
Author(s):  
E. Stark ◽  
Zs. Ács ◽  
G. B. Makara ◽  
K. Mihály
Keyword(s):  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Release Mechanism ◽  
Significant Elevation ◽  
Plasma Corticosterone Level ◽  
Corticosterone Concentration ◽  
Corticotrophin Releasing Factor ◽  
Adrenocortical Response ◽  
The Difference ◽  
Acth Release

Twenty-four hours after the last of 14 daily injections of ACTH, the administration of ether, histamine, 1% formalin, or lysine-8-vasopressin produced no rise in the plasma corticosterone level in rats but raised it significantly in saline-treated control animals. As assayed by the plasma corticosterone concentration, ACTH release was found to be inhibited when hypophyseal–adrenocortical responsiveness was not impaired and the peripheral corticosterone level was normal or less than normal. Endotoxin induced nearly the same statistically significant elevation in the ACTH-treated and saline-treated animals. It would appear that it is the high corticosterone level produced by the last ACTH injection that suppresses the corticotrophin-releasing factor (CRF) 24 h later (feedback action) when this level returns to normal or less than normal; and that certain stressors liberate CRF whereas others do not. An explanation for the latter assumption may be found either in the difference in intensity between the stimuli or, more probably, in that the high corticosterone level inhibits the ACTH release mechanism for certain individual stressors, but not for others.

PITUITARY-ADRENAL ACTIVATION IN RATS WITH HEREDITARY HYPOTHALAMIC DIABETES INSIPIDUS

1967 ◽  
Vol 54 (1) ◽  
pp. 155-165 ◽  
Author(s):  
Akira Arimura ◽  
Takashige Saito ◽  
Cyril Y. Bowers ◽  
Andrew V. Schally
Keyword(s):  
Diabetes Insipidus ◽  
Normal Structure ◽  
Plasma Corticosterone ◽  
Posterior Pituitary ◽  
Corticosterone Concentration ◽  
Corticotrophin Releasing Factor ◽  
Significant Difference ◽  
The Difference ◽  
Hereditary Hypothalamic Diabetes Insipidus ◽  
And Control

ABSTRACT Pituitary adrenal activation in rats with hereditary hypothalamic diabetes insipidus (DI) and normal control rats (Brattleboro strain) was studied under various conditions. Plasma corticosterone concentration was essentially the same in resting DI and control rats. No significant difference in plasma corticosterone was observed after giving the animals ether, histamine, vasopressin or acetylcholine. Since DI rats lack vasopressin, these findings provide some evidence that vasopressin is unlikely to be the physiological corticotrophin releasing factor (CRF). Epinephrine induced a smaller increase in plasma corticosterone in DI rats than control animals, but the difference was not statistically significant. However, intraperitoneal injection of 0.9% saline resulted in significantly less elevation of plasma corticosterone in DI rats than normal. This suggests certain differences in responses between normal and DI rats depending upon the intensity or nature of the stress. Hypothalamic CRF in control and DI rats was determined using rats treated with chlorpromazine, morphine and Nembutal®. The CRF of hypothalami of DI rats was about half of that of control animals. In the extracts of posterior pituitary lobes, corticotrophin (ACTH) activity was found in almost the same amount in DI and control rats. The posterior pituitary lobe of DI rats lacked CRF activity when tested in neurohypophysectomized rats. Histological examination of the adrenals of DI rats revealed normal structure, suggesting normal ACTH secretion at rest.

AFFERENT PATHWAYS OF STRESSFUL STIMULI: CORTICOTROPHIN RELEASE AFTER PARTIAL DEAFFERENTATION OF THE MEDIAL BASAL HYPOTHALAMUS

1969 ◽  
Vol 44 (2) ◽  
pp. 187-193 ◽  
Author(s):  
G. B. MAKARA ◽  
E. STARK ◽  
M. PALKOVITS ◽  
T. RÉVÉSZ ◽  
K. MIHÁLY
Keyword(s):  
Escherichia Coli ◽  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Neural Pathways ◽  
Plasma Corticosterone Level ◽  
Nerve Fibres ◽  
Afferent Pathways ◽  
Medial Basal Hypothalamus ◽  
Noise And Vibration ◽  
Acth Release

SUMMARY Corticotrophin (ACTH) release induced by various stressful stimuli has been studied in rats with antero-lateral deafferentation of the medial basal hypothalamus (MBH). The plasma corticosterone level was determined as an index of ACTH release. In rats with antero-lateral deafferentation of the MBH, ACTH release was prevented after exposure to noise and vibration, sham adrenalectomy and s.c. injection of 1% formalin. ACTH release induced by the injection of histamine (1 mg./100 g., i.p.) and capsaicin (0·25 mg./100 g., s.c.) was significantly less than in the controls. Escherichia coli lipopolysaccharide (25 μg./100 g., i.p.) induced an ACTH release that could not be distinguished from that in the controls. We suggest that (a) noise and vibration, sham adrenalectomy and injection of 1% formalin trigger ACTH release through neural pathways arriving at the MBH from anterior, lateral and dorsal directions, (b) histamine or capsaicin releases ACTH partly through antero-lateral neural afferents to the MBH. In contrast, the ACTH-releasing stimulus of bacterial endotoxin injection reaches the hypothalamo—hypophysial unit by humoral pathways and/or posterior nerve fibres.

CORTICOTROPHIN RELEASE INDUCED BY SURGICAL TRAUMA AFTER TRANSECTION OF VARIOUS AFFERENT NERVOUS PATHWAYS TO THE HYPOTHALAMUS

1972 ◽  
Vol 53 (3) ◽  
pp. 389-395 ◽  
Author(s):  
G. B. MAKARA ◽  
E. STARK ◽  
J. MARTON ◽  
T. MÉSZÁROS
Keyword(s):  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Surgical Trauma ◽  
Plasma Corticosterone Level ◽  
Nerve Fibres ◽  
Hypothalamic Area ◽  
Medial Basal Hypothalamus ◽  
Median Forebrain Bundle ◽  
Significant Difference ◽  
Acth Release

SUMMARY Corticotrophin (ACTH) release induced by surgical trauma under pentobarbitone anaesthesia was studied in rats. The plasma corticosterone level was used as an index of 'rapid' ACTH release. One hour after surgical trauma the plasma corticosterone level had risen in rats with various cuts around the medial basal hypothalamus except in the group with lateral cuts. After stress no significant difference was found between the plasma levels of the controls and those of the rats with anterior, 'low' superior, 'low' anterosuperior, and 'short' posterior cuts. In contrast, in rats with 'high' superior, 'high' anterosuperior, 'long' posterior and lateral cuts the plasma corticosterone level was lower than in the appropriate sham-operated controls. It is suggested that the nerve fibres initiating ACTH release after surgical trauma ascend the spinal cord to the medulla and mid-brain whence the pathways pass forward in the region of the dorsal longitudinal fasciculus and/or the median forebrain bundle to the lateral hypothalamic area, and from there to the medial basal hypothalamus.

AFFERENT PATHWAYS OF STRESSFUL STIMULI: CORTICOTROPHIN RELEASE AFTER HYPOTHALAMIC DEAFFERENTATION

1970 ◽  
Vol 47 (4) ◽  
pp. 411-NP ◽  
Author(s):  
G. B. MAKARA ◽  
E. STARK ◽  
M. PALKOVITS
Keyword(s):  
Intraperitoneal Administration ◽  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Afferent Input ◽  
Neural Pathways ◽  
Plasma Corticosterone Level ◽  
Afferent Pathways ◽  
Medial Basal Hypothalamus ◽  
E Coli ◽  
Acth Release

SUMMARY Corticotrophin (ACTH) release induced by stressful stimuli has been studied in rats with completely deafferentated medial basal hypothalamus (MBH) pituitary islands or median eminence (ME)-stalk pituitary islands. The plasma corticosterone level was used as index of ACTH release. In rats with MBH pituitary islands, capsaicin failed to raise the plasma corticosterone level, but the intraperitoneal administration of E. coli endotoxin, histamine, insulin or a large subcutaneous dose of formaldehyde caused ACTH release which could not be distinguished from that in the controls. Histamine and insulin induced ACTH release even in rats with a ME-stalk pituitary island. It is suggested that E. coli endotoxin, histamine, insulin hypoglycaemia and large doses of formaldehyde may be classified as 'humoral' stimuli of ACTH release, since a neural afferent input to the MBH is not essential for their action. On the other hand, the integrity of some neural pathways to the MBH is essential for the ACTH-releasing effect of capsaicin.

EFFECT OF STRESS AND ENVIRONMENTAL TEMPERATURE ON ADRENAL FUNCTION IN RANA ESCULENTA

1973 ◽  
Vol 57 (3) ◽  
pp. 385-391 ◽  
Author(s):  
M. JURÁNI ◽  
K. MURGAŠ ◽  
L. MIKULAJ ◽  
F. BABUŠÍKOVÁ
Keyword(s):  
Environmental Temperature ◽  
Corticosterone Level ◽  
Rana Esculenta ◽  
Plasma Corticosterone ◽  
Plasma Corticosterone Level ◽  
Corticosterone Concentration ◽  
Stress Changes ◽  
Prolonged Immobilization ◽  
Rapid Activation ◽  
Environmental Temperatures

SUMMARY The effect of immobilization for 60 min on the adrenal activity of frogs (Rana esculenta) was studied by measuring corticosterone in plasma and corticosterone and catecholamines in adrenorenal homogenates. An increase in plasma corticosterone and in noradrenaline in the adrenorenal homogenate was observed after immobilization for 5 min and there was further increase after prolonged immobilization. However, there was no change throughout the period of immobilization in the corticosterone and adrenaline content of the adrenorenal homogenates. When frogs were exposed to various environmental temperatures the resting plasma corticosterone level did not change at temperatures below 20 °C, but rose significantly at temperatures above 20 °C. No increase in plasma corticosterone concentration occurred at 1 °C after corticotrophin (ACTH) administration. At higher temperatures (up to 30 °C) a significant correlation was found between plasma corticosterone levels after ACTH administration and environmental temperature. No further increase in plasma corticosterone took place at temperatures up to 40 °C. The results indicate a rapid activation of both the interrenal and chromaffin components of the adrenal gland in Rana esculenta when subjected to this type of stress. Changes in plasma corticosterone levels resulting from changes in environmental temperature may be either an expression of specific changes in steroidogenesis of the adrenals, or of the entire metabolic activity of the organism.

Dissociation of adrenal corticosteroid production from ACTH in water-restricted female rats

1981 ◽  
Vol 241 (1) ◽  
pp. R21-R24 ◽  
Author(s):  
R. G. Doell ◽  
M. F. Dallman ◽  
R. B. Clayton ◽  
G. D. Gray ◽  
S. Levine
Keyword(s):  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Female Rats ◽  
Adrenocorticotrophic Hormone ◽  
Corticosterone Concentration ◽  
Acth Concentration

These experiments were undertaken to investigate the mechanism whereby a precipitous drop in plasma corticosterone concentration is brought about following drinking in rats on a restricted water schedule. No alteration in adrenocorticotrophic hormone (ACTH) output was found, nor was catabolism of corticosterone sufficient to account for the drop. It is concluded that corticosterone level is controlled under these conditions by a mechanism independent of ACTH concentration.

Bacopa monnieri alleviates aluminium chloride-induced anxiety by regulating plasma corticosterone level in Wistar rats

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Senthil Murugan Murugaiyan ◽  
Rajesh Bhargavan
Keyword(s):  
Oral Administration ◽  
Corticosterone Level ◽  
Tween 80 ◽  
Treated Group ◽  
Plasma Corticosterone ◽  
Bacopa Monnieri ◽  
Aluminium Chloride ◽  
Control Group ◽  
Plasma Corticosterone Level ◽  
Protective Groups

AbstractObjectivesAluminium is present in food preparations, antacids and many medications. It causes neurodegeneration thereby resulting in a spectrum of neurological disorders such as dementia, Alzheimer’s disease and anxiety. Bacopa monnieri (BM) is widely used in ayurvedic medicine to improve memory functions. Its anxiolytic property was investigated in this study by using elevated plus maze (EPM) and plasma corticosterone level.MethodsThirty rats were assigned into five groups. Control group received distilled water, and 0.5% tween 80, AlCl3 group received Aluminium Chloride (AlCl3), Protective groups (BM100 + AlCl3 group and BM200 + AlCl3 group) received AlCl3 and BM at two different doses, and the BM200 group received BM. The EPM experiment was performed at the end of the 4th week of oral administration of BM and AlCl3 followed by the measurement of plasma corticosterone.ResultsOral administration of AlCl3 to rats increases the levels of anxiety as seen in a decrease in the percentage of entries into the open arms of EPM, an increase in grooming frequency and defecation index. However, the rats in the protective groups shown an increase in the percentage of open arm entries and rearing frequency, and decreased grooming frequency and defecation index. AlCl3 alone treated group showed a significant increase in the plasma corticosterone levels compared to the control group. Whereas the protective groups have shown a significant decrease in the plasma corticosterone levels than the AlCl3 alone treated group.ConclusionsHence the BM has potential role in reverting the anxiogenic effect of AlCl3 in the amygdala as it is evident from the plasma corticosterone levels and the EPM parameters of different groups under study.

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