Vasopressin receptors influencing the secretion of ACTH by the rat adenohypophysis

1987 ◽  
Vol 113 (3) ◽  
pp. 389-396 ◽  
Author(s):  
J. C. Buckingham
Keyword(s):  
Receptor Antagonist ◽  
Arginine Vasopressin ◽  
Receptor Agonist ◽  
Intrinsic Activity ◽  
Corticotrophin Releasing Factor ◽  
Low Concentrations ◽  
Vasopressin Receptors ◽  
Acth Release

ABSTRACT The effects of selective agonists and antagonists of type 1 (V1) and type 2 (V2) vasopressin receptors on the secretion of ACTH in vitro by segments of adenohypophysial tissue and in vivo in rats pretreated with pentobarbitone and chlorpromazine were studied in the presence and absence of the 41 amino acid-containing peptide, corticotrophin-releasing factor-41 (CRF-41). The non-selective vasopressin receptor agonist, arginine vasopressin (AVP) and the V1-receptor agonist, felypressin caused dose-related increases in ACTH release in vivo and in vitro but the V2-receptor agonist, desmopressin was only weakly active in this respect. Their actions in vitro were antagonized competitively by the V1-receptor antagonist, d(C2H5)2-AVP, but were unaffected by the V2-receptor antagonist, d(CH2)5-d-Iso2-Thr4-AVP. Arginine vasopressin, felypressin and desmopressins in concentrations considerably lower than those necessary to elicit directly the release of ACTH, potentiated, in a dose-related manner, the activity of CRF-41 in vitro. The potentiating effects were not antagonized by the V2-receptor antagonist or by low concentrations of the V1 -receptor antagonist. At a higher concentration, the V1-receptor antagonist reduced, but did not abolish, the potentiating effects of AVP and its analogues. However, at this concentration, it also exhibited weak intrinsic activity and, like the agonists, potentiated the response to CRF-41. The results suggest that the direct effect of AVP on ACTH release is mediated by V1-like receptors. The vasopressin receptors involved in the potentiation of CRF-41 activity appear to be different. J. Endocr. (1987) 113, 389–396

scholarly journals The 5-HT4 receptor agonist, tegaserod, is a potent 5-HT2B receptor antagonist in vitro and in vivo

2004 ◽  
Vol 143 (5) ◽  
pp. 549-560 ◽  
Author(s):  
D T Beattie ◽  
J A M Smith ◽  
D Marquess ◽  
R G Vickery ◽  
S R Armstrong ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Receptor Agonist

scholarly journals Intrinsic activity of the non-prostanoid thromboxane A2 receptor antagonist, daltroban (BM 13,505), in human platelets in vitro and in the rat vasculature in vivo

1995 ◽  
Vol 115 (1) ◽  
pp. 210-216 ◽  
Author(s):  
Frédéric Bertolino ◽  
Jean-Pierre Valentin ◽  
Myriam Maffre ◽  
Françoise Grelac ◽  
Anne-Marie Bessac ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Thromboxane A2 ◽  
Human Platelets ◽  
Intrinsic Activity ◽  
Thromboxane A2 Receptor

Effect of selective serotonin agonists on basal, corticotrophin-releasing hormone- and vasopressin-induced ACTH release in vitro from rat pituitary cells

1993 ◽  
Vol 136 (3) ◽  
pp. 381-387 ◽  
Author(s):  
A. E. Calogero ◽  
G. Bagdy ◽  
M. L. Moncada ◽  
R. D'Agata
Keyword(s):  
Receptor Antagonist ◽  
Receptor Agonist ◽  
Receptor Subtype ◽  
Pituitary Cells ◽  
Releasing Hormone ◽  
Rat Pituitary ◽  
Rat Pituitary Cells ◽  
Level 2 ◽  
Acth Release

ABSTRACT The present study was undertaken to evaluate the serotonin (5-HT) receptor subtype(s) by which 5-HT acts on the pituitary to stimulate ACTH secretion. We tested the effects of the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT), the 5-HT1C receptor agonist metachloro-phenylpiperazine (m-CPP), which also binds to other 5-HT receptors with lower affinity, and the 5-HT2/1C receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on basal, corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP)-stimulated ACTH release from primary rat anterior pituitary cell cultures. 5-HT, 8-OH-DPAT and DOI significantly increased basal ACTH release, an effect which was antagonized by 5-HT receptor antagonists. 5-HT and DOI were effective at nanomolar concentrations whereas 8-OH-DPAT was effective at higher concentrations. 5-HT, 8-OH-DPAT (both at 10 nmol/l) and DOI (at higher concentrations) blunted the stimulatory effect of CRH. The suppressive effects of 8-OH-DPAT and DOI on CRH-stimulated ACTH release were antagonized by (−)propranolol, a β-adrenergic receptor antagonist which binds the 5-HT1A receptor with elevated affinity, and ketanserin, a 5-HT2 receptor antagonist respectively. 5-HT, 8-OH-DPAT and DOI showed additive stimulatory effects with AVP but only at the highest concentration tested, whereas m-CPP potentiated AVP-induced ACTH release at concentrations of 1 nmol/l or more. This effect was antagonized by metergoline, a non-selective 5-HT receptor antagonist and mianserin, an antagonist which binds the 5-HT1C receptor with elevated affinity. Thus (1) 5-HT and selective 5-HT agonists such as 8-OH-DPAT, m-CPP and DOI modulate ACTH release by acting directly at the pituitary level; (2) serotonergic stimulation of basal ACTH release is mediated by both 5-HT2 and 5-HT1A receptors; (3) serotonergic inhibition of CRH-stimulated ACTH release is mediated by 5-HT1A and 5-HT2 receptors; whereas (4) serotonergic potentiation of AVP-stimulated ACTH release is mediated mainly by 5-HT1C receptors. Journal of Endocrinology (1993) 136, 381–387

SLV313 is a dopamine D2 receptor antagonist and serotonin 5-HT1A receptor agonist: In vitro and in vivo neuropharmacology

2002 ◽  
Vol 12 ◽  
pp. 277 ◽  
Author(s):  
J. Glennon ◽  
A.C. McCreary ◽  
E. Ronken ◽  
R. Siarey ◽  
M.B. Hesselink ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Receptor Agonist ◽  
Dopamine D2 Receptor ◽  
D2 Receptor ◽  
Dopamine D2 ◽  
Dopamine D2 Receptor Antagonist

ACTH secretion from isolated hypophysial anterior lobes of male and female newborn rats: effects of corticotrophin-releasing factor, arginine vasopressin and oxytocin alone or in combination

1993 ◽  
Vol 137 (1) ◽  
pp. 123-132 ◽  
Author(s):  
L. Hary ◽  
J. P. Dupouy ◽  
A. Chatelain
Keyword(s):  
Arginine Vasopressin ◽  
Anterior Pituitary ◽  
Newborn Rats ◽  
Acth Secretion ◽  
Peripheral Plasma ◽  
Corticotrophin Releasing Factor ◽  
Males And Females ◽  
Dose Dependent ◽  
Acth Release

ABSTRACT ACTH release by the anterior pituitary lobes of 8-day-old newborn rats (males and females) in the presence of rat corticotrophin-releasing factor (rCRF), arginine vasopressin (AVP) and oxytocin, given alone or in association, was measured in vitro. Rat CRF and AVP induced a dose-dependent release of ACTH in both sexes, while oxytocin was unable to stimulate ACTH secretion except at the highest dose tested. No sex-related difference was noted for any of the responses. Oxytocin (1 nmol/l) potentiated the response to rCRF (0·20 nmol/l) by the anterior pituitary lobes of females but not by those of males. This oxytocin potentiation was abolished when female newborn rats were injected at birth with testosterone (1 mg). AVP (1 nmol/l) alone stimulated ACTH release from the anterior pituitary lobes of the newborn rats of both sexes and markedly potentiated the ACTH response to rCRF. Although no difference between the sexes was noted for basal levels of AVP and oxytocin in the hypothalamus, the neurointermediate lobe and the peripheral plasma, the present data on the sex-related effect of oxytocin on the newborn adenohypophysis could, in part, explain why ACTH release in response to ether stress was previously reported to be more lasting in females than in males on day 8 postpartum. Journal of Endocrinology (1993) 137, 123–132

In-vitro effects of corticosterone, synthetic ovine corticotrophin releasing factor and arginine vasopressin on the release of adrenocorticotrophin by fetal rat pituitary glands

1984 ◽  
Vol 101 (3) ◽  
pp. 339-344 ◽  
Author(s):  
J. P. Dupouy ◽  
A. Chatelain
Keyword(s):  
Arginine Vasopressin ◽  
Fetal Life ◽  
Spontaneous Release ◽  
Sharp Rise ◽  
Corticotrophin Releasing Factor ◽  
Fetal Rat ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Acth Release

ABSTRACT The in-vitro release of ACTH by fetal rat pituitary glands on days 17, 19 and 21 of pregnancy was measured using radioimmunoassay. The spontaneous release of ACTH, expressed in pg ACTH/gland per h, increased with fetal age, in correlation with the sharp rise in pituitary ACTH content. However, since pituitary ACTH content was nearly sevenfold higher at term than on day 17, while basal release of ACTH was only threefold higher, one can speculate that the spontaneous release of ACTH was proportionally greater on day 17 than on day 21 of gestation. As corticosterone, at a physiological concentration (865 nmol/l), reduced ACTH release, it was concluded that the pituitary gland was one site of the negative feedback action of the corticosteroids during fetal life. Quantities of synthetic ovine corticotrophin releasing factor (CRF) which gave concentrations of 0·3–30 nmol/l in the incubation medium induced a sharp rise in ACTH release which was log-dose dependent between 0·3 and 3 nmolCRF/1 on day 17 and between 0·3 and 30 nmolCRF/1 on days 19 and 21. The response to CRF increased with fetal age. Quantities of arginine vasopressin (AVP) which gave concentrations of 2–200 nmol/l stimulated ACTH release at all stages of gestation investigated. However, the response to AVP was much lower than that to CRF. Potentiation of CRF-induced ACTH release was not observed when whole pituitary glands from 21-day-old fetuses were incubated with AVP (20 nmol/l) + CRF (3 nmol/l). Such results were correlated with the ontogenesis of immunoreactive vasopressin- and CRF-containing fibres in the median eminence of the rat fetus, as well as with the CRF-like immunoreactivity present in adult rat pituitary portal plasma and the AVP content of the fetal rat hypophysis. J. Endocr. (1984) 101, 339–344

Effects of rat corticotrophin-releasing factor, arginine vasopressin and oxytocin on the secretions of adrenocorticotrophic hormone and corticosterone in the fetal rat in late gestation: in vivo and in vitro studies

1994 ◽  
Vol 130 (3) ◽  
pp. 313-319 ◽  
Author(s):  
S Deloof ◽  
V Montel ◽  
A Chatelain
Keyword(s):  
Arginine Vasopressin ◽  
Anterior Pituitary ◽  
Late Gestation ◽  
Adrenocorticotrophic Hormone ◽  
Rat Fetuses ◽  
Corticotrophin Releasing Factor ◽  
Fetal Rat ◽  
Pituitary Glands

Deloof S, Montel V, Chatelain A. Effects of rat corticotrophin-releasing factor, arginine vasopressin and oxytocin on the secretions of adrenocorticotrophic hormone and corticosterone in the fetal rat in late gestation: in vivo and in vitro studies. Eur J Endocrinol 1994;130:313–19. ISSN 0804–4643 The effects of rat corticotrophin-releasing factor (rCRF), arginine vasopressin (AVP) and oxytocin (OT) were investigated in vivo in 21 -day-old rat fetuses injected through the umbilical vein and in vitro on perifused anterior pituitary glands from 21-day-old rat fetuses. In vivo, rCRF (1.25 pmol • 50 μl−1 • fetus−1), AVP (5 pmol • 50 μl−1 •fetus−1) alone and rCRF in association with AVP or oxytocin (12.5 pmol • 50 μl−1 • fetus−1) increased plasma adrenocorticotrophic hormone (ACTH) and corticosterone levels only 30 min after the start of injection. During the first 10 min of the sampling period, the injection of these peptides alone or in combination and the injection of saline decreased the plasma ACTH concentration, which was lower than that of uninjected fetuses, but had no effect on the plasma corticosterone concentration. In vitro, the release of ACTH by perifused anterior pituitary glands was increased strongly by rCRF (4 pmol/0.5 ml) but only slightly by AVP (92 pmol/0.5 ml) and oxytocin (198 pmol/0.5 ml). Arginine vasopressin and oxytoxin potentiated the release of ACTH stimulated by rCRF in vitro but not in vivo. Our results suggest that rCRF is the major peptide that controls ACTH secretion in the fetal rat at term. In conclusion, the rise of the ACTH level observed only 30 min after injection of rCRF or AVP suggests the existence of a factor able to inhibit the ACTH response after injection of these peptides. This factor might be elicited by the blood volume expansion. A Chatelain, Laboratoire de Neuroendocrinologie du Développement, Université des Sciences et Technologies de Lille, Bâtiment SN4, 59655 Villeneuve d'Ascq cédex, France

Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
Author(s):  
C. Schümichen ◽  
B. Mackenbrock ◽  
G. Hoffmann
Keyword(s):  
Normal Saline ◽  
Half Life ◽  
Compound A ◽  
Short Half Life ◽  
Low Concentrations ◽  
The Stability ◽  
Kinetics Of ◽  
In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

scholarly journals Synthesis, in vitro and in vivo evaluation of 11C-O-methylated arylpiperazines as potential serotonin 1A (5-HT1A) receptor antagonist radiotracers

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Vidya Narayanaswami ◽  
Junchao Tong ◽  
Ferdinando Fiorino ◽  
Beatrice Severino ◽  
Rosa Sparaco ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
In Vivo Evaluation
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