Glucocorticoid receptors in PVN: interactions with NE, NPY, and Gal in relation to feeding

1993 ◽  
Vol 265 (5) ◽  
pp. E794-E800 ◽  
Author(s):  
D. L. Tempel ◽  
S. F. Leibowitz
Keyword(s):  
Glucocorticoid Receptors ◽  
Steroid Receptors ◽  
Carbohydrate Intake ◽  
Type I ◽  
Fat Intake ◽  
Type Ii ◽  
Stimulatory Action ◽  
Carbohydrate Ingestion ◽  
Ru 486 ◽  
Ru 28318

Norepinephrine (NE) and neuropeptide Y (NPY) potentiate carbohydrate ingestion after injection into the paraventricular nucleus (PVN), whereas injection of galanin (Gal) potentiates fat intake. The present study examines the relation between these neurochemically induced feeding behaviors and the adrenal steroids acting locally within the PVN. Results demonstrate that PVN NE- and NPY-induced carbohydrate intake is abolished by adrenalectomy surgery (ADX) and by local PVN implants of the type II receptor antagonist RU-486. Carbohydrate intake in response to PVN NE or NPY injection is unaffected by the type I antagonist RU-28318. In contrast, the stimulatory effect of PVN Gal injection on fat intake is unchanged by surgical ADX or by PVN administration of RU-486 or RU-28318, suggesting that the stimulatory action of Gal on fat ingestion occurs independently of corticosterone (Cort) and of PVN type I or type II steroid receptors. It is concluded that endogenous Cort has a permissive effect on the carbohydrate feeding responses elicited by NE and NPY in the PVN and that this interaction is mediated by type II glucocorticoid receptors within this nucleus.

Type II glucocorticoid receptors in the CNS regulate metabolism in ob/ob mice independent of protein synthesis

1994 ◽  
Vol 266 (3) ◽  
pp. E427-E432
Author(s):  
H. L. Chen ◽  
D. R. Romsos
Keyword(s):  
Protein Synthesis ◽  
Glucocorticoid Receptors ◽  
Type I ◽  
Intracerebroventricular Injection ◽  
Type Ii ◽  
Ru 486 ◽  
Brown Adipose ◽  
Brown Adipose Tissue Thermogenesis ◽  
Cerebral Protein Synthesis ◽  
Corticoid Receptor

A single intracerebroventricular injection of dexamethasone rapidly (within 30 min) decreases brown adipose tissue thermogenesis by 25% as assessed by GDP binding and increases plasma insulin twofold in adrenalectomized ob/ob mice. The present study investigated the type of corticoid receptor(s) that mediate these effects and determined whether protein synthesis was necessary for expression of these glucocorticoid actions in ob/ob mice. Intracerebroventricular injection of aldosterone (a type I-corticoid receptor agonist) was ineffective in altering peripheral metabolism in adrenalectomized ob/ob mice, whereas RU-486 (a type II-corticoid receptor antagonist) abolished the effects of dexamethasone. Thus type II-like corticoid receptors, not type I receptors, mediated the rapid effects of dexamethasone in adrenalectomized ob/ob mice. Anisomycin (0.5 mg) administered subcutaneously almost completely suppressed (-92%) cerebral protein synthesis, but anisomycin did not abolish the rapid effects of dexamethasone in adrenalectomized ob/ob mice. Thus protein synthesis is not a prerequisite for rapid effects of dexamethasone in adrenalectomized ob/ob mice.

Mifepristone (RU 486), a blocker of type II glucocorticoid and progestin receptors, reverses a dietary form of obesity

1992 ◽  
Vol 262 (6) ◽  
pp. R1106-R1110 ◽  
Author(s):  
S. Okada ◽  
D. A. York ◽  
G. A. Bray
Keyword(s):  
Body Weight ◽  
Glucocorticoid Receptors ◽  
Body Weight Gain ◽  
The Body ◽  
Receptor Activity ◽  
Minor Role ◽  
Type Ii ◽  
Fat Pad ◽  
Ru 486 ◽  
A Minor

The effect of mifepristone (RU 486), a blocker of type II glucocorticoid receptors on the development of obesity that follows the feeding of a high-fat (HF) diet to Osborne-Mendel (OM) rats, has been investigated. OM rats fed a HF diet gained more weight and had larger retroperitoneal and parametrial fat pads than OM rats fed a high-carbohydrate low-fat (LF) diet. RU 486 (30 mg.kg-1.day-1) for 14 days completely reversed the body weight gain and the increase in fat pad size of OM rats fed a HF diet. RU 486 had no effect on body weight of OM rats fed a LF diet, but did reduce fat pad weights. The data suggest that type II glucocorticoid receptor activity modulates body fat deposition and is essential for the development of obesity, although a minor role for progestin receptor activity cannot be ruled out.

scholarly journals Regulatory role of BMP2 and BMP7 in spermatogonia and Sertoli cell proliferation in the immature mouse

2004 ◽  
pp. 511-520 ◽  
Author(s):  
R Puglisi ◽  
M Montanari ◽  
P Chiarella ◽  
M Stefanini ◽  
C Boitani
Keyword(s):  
Cell Proliferation ◽  
Sertoli Cell ◽  
Receptor Expression ◽  
Postnatal Life ◽  
Type I ◽  
Type Ii ◽  
Testicular Cell ◽  
Stimulatory Action ◽  
Paracrine Signalling ◽  
Receptor Complexes

AIM: The aim of this study was to determine the action of bone morphogenetic proteins (BMPs) on testicular cell proliferation during early postnatal life, a definite developmental time at which crucial changes in germ cell and Sertoli cell maturation occur. METHODS: We investigated the effect of BMP2 and BMP7, two factors which belong to the relatively distant decapentaplegic (DPP) and 60 A classes of the large BMP family, upon spermatogonial and Sertoli cell proliferation, and we examined the expression of activin/BMP type II and type I receptors. We used in vitro cultured testis fragments from 7-day-old mice, highly purified populations of somatic and germ cells and total testes from mice of different ages. Cell proliferation was assessed by BrdU labelling and [3H]-thymidine incorporation. Ribonuclease protection assays and Northern blotting were performed to analyse receptor expression. RESULTS AND CONCLUSIONS: We have demonstrated a stimulatory action of BMP2 and BMP7 in spermatogonia and Sertoli cell proliferation respectively. ActRIIB is the type II receptor expressed most in spermatogonia, whereas Sertoli cells specifically expressed BMPRIIB, in addition to ActRIIB. By contrast, the presence of ActRIIA was undetectable in either germ or somatic cells. The type I receptors ActRIA, ActRIB and BMPRIA were all found in both cell types, indicating that the observed effect of BMP2 and BMP7 on testicular cell proliferation may be mediated by a number of combinatorial interactions in the receptor complexes. These findings suggest that BMPs are involved in physiological paracrine signalling during the first wave of spermatogenesis.

CARBOHYDRATE INGESTION IMPROVES OXIDATIVE ATP RESYNTHESIS IN TYPE I AND TYPE II MUSCLE FIBRES DURING PROLONGED EXERCISE.

1998 ◽  
Vol 30 (Supplement) ◽  
pp. 175
Author(s):  
K. Tsintzas ◽  
C. Williams ◽  
D. Constantin-Teodosiu ◽  
E. Hultman ◽  
L. Boobis ◽  
...  
Keyword(s):  
Prolonged Exercise ◽  
Muscle Fibres ◽  
Type I ◽  
Type Ii ◽  
Carbohydrate Ingestion

Effects of corticoid agonists and antagonists on apical Na+ permeability of toad urinary bladder

1994 ◽  
Vol 266 (1) ◽  
pp. F108-F116 ◽  
Author(s):  
H. Garty ◽  
K. Peterson-Yantorno ◽  
C. Asher ◽  
M. M. Civian
Keyword(s):  
Urinary Bladder ◽  
Glucocorticoid Receptors ◽  
Membrane Vesicles ◽  
Receptor Occupancy ◽  
Toad Urinary Bladder ◽  
Type I ◽  
Type Ii ◽  
Plasma Membrane Vesicles ◽  
Mineralocorticoid Antagonist ◽  
Amphibian Urinary Bladder

Effects of RU-28362 (glucocorticoid agonist), RU-38486 (glucocorticoid antagonist), and RU-26752 (mineralocorticoid antagonist) on the apical Na+ permeability of toad bladder were measured and correlated with occupancies of cytosolic type I (mineralocorticoid) and type II (glucocorticoid) receptors. Effects of the above steroids were measured in whole bladders, plasma membrane vesicles, and RNA-injected Xenopus oocytes. RU-38486 was found to fully displace aldosterone from type II receptors without affecting type I occupancy. Under these conditions, RU-38486 inhibited approximately 35% of the effect of aldosterone measured in the whole tissue and isolated membranes. Unexpectedly, oocytes injected with RNA from tissue stimulated with aldosterone plus RU-38486 expressed channel activity that was much higher than the sum of activities induced by either steroid alone. RU-28362 and RU-26752 at concentrations sufficient to fully occupy both receptors had only partial agonistic and antagonistic effects, respectively. The results suggest that at least one-third of the natriferic action of aldosterone measured in the amphibian urinary bladder is mediated by the glucocorticoid receptor. However, some of the effects observed cannot be accounted for by a simple receptor occupancy-response scheme.

Aldosterone receptors in A6 cells: physicochemical characterization and autoradiographic study

1989 ◽  
Vol 257 (4) ◽  
pp. C665-C677 ◽  
Author(s):  
M. Claire ◽  
B. Machard ◽  
M. Lombes ◽  
M. E. Oblin ◽  
J. P. Bonvalet ◽  
...  
Keyword(s):  
Glucocorticoid Receptors ◽  
Physicochemical Characterization ◽  
Sedimentation Coefficient ◽  
Size Exclusion ◽  
Type I ◽  
Type Ii ◽  
Homogeneous Population ◽  
Binding Characteristics ◽  
A6 Cells ◽  
Receptor Complexes

The A6 cell line is derived from the kidney of Xenopus laevis. Aldosterone increases sodium transport across A6 cell epithelia. In the present study, aldosterone binding characteristics were studied in A6 cell cytosol. Both type I (mineralocorticoid) and type II (glucocorticoid) receptors are present in the cytosolic fraction of these cells. Aldosterone and corticosterone had a high affinity for type I sites (Kd = 1.25 and 0.16 nM, respectively) and a lower affinity for type II sites (Kd = 39 and 10 nM, respectively). Testosterone and estradiol did not compete for aldosterone binding. RU 26988, a highly specific glucocorticoid agonist, competed with aldosterone for type II but not for type I sites. Hydrodynamic parameters of both type I and type II corticosterone receptor complexes were identical. Their Stokes radius was approximately 6 nm, as estimated by high-performance size-exclusion chromatography, and their sedimentation coefficient determined by ultracentrifugation on glycerol gradients was approximately 9s. The molecular mass calculated from these parameters was approximately 200 kDa, a value that is very close to the value estimated for nontransformed mineralocorticoid and glucocorticoid receptors of other species. The [3H]aldosterone labeling of intact A6 cells was examined by autohistoradiography. At every concentration tested (2, 20, and 50 nM), all cells were found to be specifically labeled in both cytoplasm and nucleus. At 20 nM, in the presence of an excess of RU 26988, labeling was also detected. At every concentration the labeling data was compatible with a Gaussian distribution, indicating that A6 cells correspond to a homogeneous population with regard to aldosterone binding and that probably both type I and type II sites are present in the same cells.

Sign in / Sign up

Export Citation Format

Share Document