Pituitary-Adrenal Function in the Absence of Vasopressin

McCann, Samuel M.; Antunes‐Rodrigues, José; Nallar, R; Valtin, Heinz

doi:10.1210/endo-79-6-1058

Cited by 99 publications

(23 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…rats in various ways, many differences possibly associated secondarily with the loss of vasopressin. These include impaired growth (Haack, Homsy, Kohrs, Mohring, Oster & Mohring, 1975), an impaired ability to learn avoidance behaviour in response to noxious stimuli (Bohus, Van Wimersma Greidanus, & De Wied, 1975) and an impaired adrenal response to stress (McCann, Antunes-Rodriguez, Nallar & Valtin, 1966). This latter impairment may be particularly relevant since glucocorticoids appear to be necessary for the normal response to stress, such as the restitution of blood volume after haemorrhage (Gann & Pirkle, 1975).…”

Section: Resultsmentioning

confidence: 99%

The cardiovascular effects of vasopressin after haemorrhage in anaesthetized rats.

Chapman¹,

Hreash²,

Laycock³

et al. 1986

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. The cardiovascular effects of an acute haemorrhage (2 % of the body weight)were studied over a 60 min period in three groups of rats: (a) Brattleboro rats with hereditary hypothalamic diabetes insipidus (b.d.i.) lacking circulating vasopressin, (b) control rats of the parent Long Evans (l.e.) strain, and (c) l.e. rats treated with an antagonist of the vascular action of vasopressin.2. Prior to the haemorrhage there were no significant differences between the three groups of rats with respect to mean arterial blood pressure, cardiac output, stroke volume or total peripheral resistance.3. Following the haemorrhage cardiac output and stroke volume were severely reduced in all three groups of rats. Total peripheral resistance was relatively unaffected in antagonist-treated l.e. rats and b.d.i. rats, but rose substantially in response to the loss of blood in the control l.e. group. Both total peripheral resistance and mean arterial blood pressure were markedly greater in the untreated l.e. control rats than in the other two groups of animals during the first 20 min after haemorrhage.4. The mean heart rate measured in Brattleboro rats was elevated compared with that of control l.e. rats throughout the experiment and, in addition, significantly greater than that of antagonist-treated l.e. rats during the first 40 min after the haemorrhage.5. Survival rate for the b.d.i. rats following the 2 % haemorrhage was lower than that for l.e. control rats and antagonist-treated l.e. rats.6. The results indicate that the recovery of the blood pressure following an acute arterial haemorrhage is significantly influenced by vasopressin, particularly during the first 20 min, and that the predominant effect of the hormone is to increase the total peripheral resistance. The higher mortality associated with volume depletion in the b.d.i. rats is unlikely to be directly related to the absence of the vascular action of vasopressin, since administration of the vasopressin antagonist to normal l.e. rats does not reduce their survival rate.

show abstract

Section: Resultsmentioning

confidence: 99%

The cardiovascular effects of vasopressin after haemorrhage in anaesthetized rats.

Chapman¹,

Hreash²,

Laycock³

et al. 1986

The Journal of Physiology

View full text Add to dashboard Cite

show abstract

“…The ACTH content of the adenohypophysis is readily influenced by minor stressful stimuli (Buckingham, 1979) and, therefore, the housing conditions, handling regimes and techniques for collecting the tissue are all important. Furthermore, the animals used in our experiments were weight-matched while those employed by McCann et al (1966) and The reduced corticotrophic activity of the anterior pituitary tissue from rats with inherited diabetes insipidus is probably the result of lack of trophic stimuli from the hypothalamus in vivo. The present data not only confirm previous findings that the CRF content of hypothalami from Brattleboro rats is reduced (Krieger, Liotta & Brownstein, 1977;Gillies & Lowry, 1979) but also show that the ability of the organ to secrete CRF in response to acetylcholine or 5-hydroxytryptamine is impaired.…”

Section: Resultsmentioning

confidence: 99%

“…Nevertheless, a substantial amount of evidence suggests that vasopressin may be involved in the sequence of events which leads to ACTH secretion (McCann, AntunesRodrigues, Nallar & Valtin, 1966;Yates, Russell, Dallman, Hedge, McCann & Dhariwal, 1971). Attempts to investigate this aspect of hypothalamo-pituitaryadrenocortical physiology in rats congenitally lacking vasopressin (Brattleboro 0022-3751/80/1380-0636 $07.50 © 1980 The Physiological Society strain) have yielded conflicting data (McCann et al 1966;Arimura, Saito, Bowers & Schally, 1967), probably because only indirect or insensitive methods were employed to assess hypothalamo-pituitary adrenocorticotrophic activity. Sensitive and precise bioassay methods for the determination of ACTH (Alaghband-Zadeh, Daly, Bitensky & Chayen, 1974) and CRF (Buckingham & Hodges, 1977a) have been developed recently for the measurement of very small changes in the concentrations of these hormones.…”

Section: Introductionmentioning

confidence: 99%

Hypothalamo‐pituitary‐adrenocortical function in rats with inherited diabetes insipidus.

Buckingham¹,

Leach²

1980

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. Hypothalamo-pituitary-adrenocortical activity in male homozygous and heterozygous Brattleboro rats was compared with that in normal (Long Evans) controls in an attempt to elucidate the role of vasopressin in the control of the secretion of corticotrophin.2. The concentrations of corticosterone and corticotrophin in the plasma, corticotrophin in the adenohypophyses and corticotrophin releasing factor in the hypothalami were lower in the heterozygotes than in the controls and lower still in the homozygotes.3. The capacities of adenohypophyses and hypothalami to secrete in vitro corticotrophin and corticotrophin releasing factor respectively in response to trophic stimuli were also reduced in the heterozygotes and, to an even greater extent, in the homozygotes.4. The results suggest that vasopressin is not the corticotrophin releasing factor but they do not exclude the possibility that it may be involved in the sequence of events which leads to the secretion of corticotrophin in the rat.

show abstract

“…It is well recognized that CRF and AVP interact synergistically to stimulate ACTH secretion (47)(48)(49)(50)(51), and studies in either AVP-deficient (Brattleboro) or normal rats treated with an anti-AVP serum or AVP receptor antagonists have shown that in the absence of AVP signaling, pituitary-adrenal responses to stressful stimuli are blunted (52)(53)(54)(55)(56)(57). The present studies are the first of which we are aware that show that the acute removal of AVP availability for interaction with its receptors in vivo blunts the pituitary ACTH response to CRF itself and indicate that endogenous AVP potentiates the response to elevated levels of CRF.…”

Section: Discussionmentioning

confidence: 99%

Urocortin Is Not a Significant Regulator of Intermittent Electrofootshock-Induced Adrenocorticotropin Secretion in the Intact Male Rat

Turnbull

1999

Endocrinology

View full text Add to dashboard Cite

Urocortin (Ucn) is a newly identified mammalian member of the CRF family of peptides. Ucn activates CRF receptors (both CRF-R1 and CRF-R2) with greater potency than CRF itself, suggesting that Ucn may play an endogenous role in eliciting (at least some) CRF receptor-mediated events. Because the most characterized physiological function of CRF receptors is the activation of pituitary ACTH secretion, we have compared the effects and potential endogenous roles of CRF and Ucn in regulating plasma ACTH concentrations in intact male rats. Synthetic rat Ucn injected iv (0.09 -9.0 nmol/kg) elicited ACTH secretion in a dose-dependent manner, causing greater ACTH secretion than CRF at each dose tested. The increases in plasma ACTH concentrations produced by CRF or Ucn were virtually abolished by pretreatment with the CRF receptor antagonist, astressin (3 mg/kg), and were partially attenuated (by 27-37%) by an antiarginine vasopressin serum. These data indicate that both Ucn and CRF elicit ACTH secretion via CRF receptor-dependent mechanisms, and that the ACTH-releasing activities of both CRF and Ucn are potentiated by endogenous arginine vasopressin. Intravenous administration of rabbit anti-Ucn serum, which inhibited ACTH secretion produced by Ucn, but not CRF, had no statistically significant effect on either resting (midday) plasma ACTH concentrations or the rise in ACTH levels elicited by 30 min of intermittent electrofootshocks. By contrast, treatment with a rabbit anti-CRF serum that specifically inhibited the ACTH response to CRF lowered plasma concentrations in control unstressed rats and largely prevented the plasma ACTH response to electrofootshocks. These data indicate that although Ucn is a more potent ACTH secretagogue than CRF in the intact male rat, it is not a major endogenous regulator of pituitary ACTH secretion under basal (midday) conditions or during acute footshock stress. (Endocrinology 140: [71][72][73][74][75][76][77][78] 1999) C RF IS A 41-amino acid mammalian neurohormone that is best known as the major physiological regulator of pituitary ACTH secretion and, in addition, stimulates complimentary stress-related endocrine, autonomic, and behavioral responses (1-5). CRF belongs to a family of structurally related peptides, including amphibian sauvagine and piscine urotensin I (4, 5). The effects of CRF-related peptides in mammalian systems are mediated via interaction with a number of distinct CRF receptors that have distinct pharmacologies and fairly exclusive anatomical distributions (6 -10). CRF receptor type I (CRF-R1) messenger RNA (mRNA) is expressed in the brain and pituitary (6,(11)(12)(13)(14)(15). Within the pituitary CRF-R1 mRNA is colocalized with ACTH immunoreactivity, indicating that CRF-R1 is expressed by corticotropes (6). CRF-R2 has at least two splice variants; in the rat, 2␣ mRNA is found only in the brain, whereas 2␤ is present in both the brain and peripheral tissues (heart, skeletal muscle), but not the pituitary (7-9, 16 -19). In addition to interacting with CRF r...

show abstract

Pituitary-Adrenal Function in the Absence of Vasopressin

Cited by 99 publications

References 0 publications

The cardiovascular effects of vasopressin after haemorrhage in anaesthetized rats.

The cardiovascular effects of vasopressin after haemorrhage in anaesthetized rats.

Hypothalamo‐pituitary‐adrenocortical function in rats with inherited diabetes insipidus.

Urocortin Is Not a Significant Regulator of Intermittent Electrofootshock-Induced Adrenocorticotropin Secretion in the Intact Male Rat

Contact Info

Product

Resources

About