Presence of estradiol-binding proteins in gastrointestinal tract of male rats

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

In the cytosol from pancreas, fundus, and antrum of rats, two classes of specific, estradiol (E2)-binding proteins (EBPs) were observed, with 5- to 10-fold differences in their binding capacities. EBPs, both type I [high affinity, dissociation constant (K(d))<1.0 nM] and type II (low affinity, K(d)>5 nM), in the fundus were found to be specific for estrogens. None of the corticoids, or androgenic and progesteronic steroids tested demonstrated any significant inhibition of binding of radiolabeled E2 to EBP at doses as high as 5 x 10-6 to 5 x 10-5 M. At high concentrations of E2 (>2-5 nM), nonsaturable EBPs were additionally observed in the pancreatic cytosol. In the intestine, however, EBP was not detected at E2 concentrations of less than 2-5 nM. Similarly, progesterone-binding proteins were nonmeasurable in either pancreas or gastrointestinal tissues at less than 5 nM concentrations of the ligand, indicating questionable physiological significance of the latter binding sites. The two classes of EBPs in the pancreas and stomach of rats, measured at near physiological E2 concentrations of less than 2 nM, however, may play a significant role in gastric and pancreatic functions, since sex steroids have been documented to have specific effects on structure and function of pancreas and stomach.

Original languageEnglish (US)
Pages (from-to)1648-1653
Number of pages6
JournalEndocrinology
Volume119
Issue number4
StatePublished - 1986

Fingerprint

Gastrointestinal Tract
Estradiol
Carrier Proteins
Pancreas
Stomach
Cytosol
Progesterone-Binding Globulin
Steroids
Intestines
Adrenal Cortex Hormones
Estrogens
Binding Sites
Ligands

ASJC Scopus subject areas

  • Endocrinology
  • Endocrinology, Diabetes and Metabolism

Cite this

Presence of estradiol-binding proteins in gastrointestinal tract of male rats. / Singh, Pomila; Townsend, Courtney; Thompson, J. C.

In: Endocrinology, Vol. 119, No. 4, 1986, p. 1648-1653.

Research output: Contribution to journalArticle

@article{e977196a363148d79cad623e8e36a0f8,
title = "Presence of estradiol-binding proteins in gastrointestinal tract of male rats",
abstract = "In the cytosol from pancreas, fundus, and antrum of rats, two classes of specific, estradiol (E2)-binding proteins (EBPs) were observed, with 5- to 10-fold differences in their binding capacities. EBPs, both type I [high affinity, dissociation constant (K(d))<1.0 nM] and type II (low affinity, K(d)>5 nM), in the fundus were found to be specific for estrogens. None of the corticoids, or androgenic and progesteronic steroids tested demonstrated any significant inhibition of binding of radiolabeled E2 to EBP at doses as high as 5 x 10-6 to 5 x 10-5 M. At high concentrations of E2 (>2-5 nM), nonsaturable EBPs were additionally observed in the pancreatic cytosol. In the intestine, however, EBP was not detected at E2 concentrations of less than 2-5 nM. Similarly, progesterone-binding proteins were nonmeasurable in either pancreas or gastrointestinal tissues at less than 5 nM concentrations of the ligand, indicating questionable physiological significance of the latter binding sites. The two classes of EBPs in the pancreas and stomach of rats, measured at near physiological E2 concentrations of less than 2 nM, however, may play a significant role in gastric and pancreatic functions, since sex steroids have been documented to have specific effects on structure and function of pancreas and stomach.",
author = "Pomila Singh and Courtney Townsend and Thompson, {J. C.}",
year = "1986",
language = "English (US)",
volume = "119",
pages = "1648--1653",
journal = "Endocrinology",
issn = "0013-7227",
publisher = "The Endocrine Society",
number = "4",

}

TY - JOUR

T1 - Presence of estradiol-binding proteins in gastrointestinal tract of male rats

AU - Singh, Pomila

AU - Townsend, Courtney

AU - Thompson, J. C.

PY - 1986

Y1 - 1986

N2 - In the cytosol from pancreas, fundus, and antrum of rats, two classes of specific, estradiol (E2)-binding proteins (EBPs) were observed, with 5- to 10-fold differences in their binding capacities. EBPs, both type I [high affinity, dissociation constant (K(d))<1.0 nM] and type II (low affinity, K(d)>5 nM), in the fundus were found to be specific for estrogens. None of the corticoids, or androgenic and progesteronic steroids tested demonstrated any significant inhibition of binding of radiolabeled E2 to EBP at doses as high as 5 x 10-6 to 5 x 10-5 M. At high concentrations of E2 (>2-5 nM), nonsaturable EBPs were additionally observed in the pancreatic cytosol. In the intestine, however, EBP was not detected at E2 concentrations of less than 2-5 nM. Similarly, progesterone-binding proteins were nonmeasurable in either pancreas or gastrointestinal tissues at less than 5 nM concentrations of the ligand, indicating questionable physiological significance of the latter binding sites. The two classes of EBPs in the pancreas and stomach of rats, measured at near physiological E2 concentrations of less than 2 nM, however, may play a significant role in gastric and pancreatic functions, since sex steroids have been documented to have specific effects on structure and function of pancreas and stomach.

AB - In the cytosol from pancreas, fundus, and antrum of rats, two classes of specific, estradiol (E2)-binding proteins (EBPs) were observed, with 5- to 10-fold differences in their binding capacities. EBPs, both type I [high affinity, dissociation constant (K(d))<1.0 nM] and type II (low affinity, K(d)>5 nM), in the fundus were found to be specific for estrogens. None of the corticoids, or androgenic and progesteronic steroids tested demonstrated any significant inhibition of binding of radiolabeled E2 to EBP at doses as high as 5 x 10-6 to 5 x 10-5 M. At high concentrations of E2 (>2-5 nM), nonsaturable EBPs were additionally observed in the pancreatic cytosol. In the intestine, however, EBP was not detected at E2 concentrations of less than 2-5 nM. Similarly, progesterone-binding proteins were nonmeasurable in either pancreas or gastrointestinal tissues at less than 5 nM concentrations of the ligand, indicating questionable physiological significance of the latter binding sites. The two classes of EBPs in the pancreas and stomach of rats, measured at near physiological E2 concentrations of less than 2 nM, however, may play a significant role in gastric and pancreatic functions, since sex steroids have been documented to have specific effects on structure and function of pancreas and stomach.

UR - http://www.scopus.com/inward/record.url?scp=0023023130&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023023130&partnerID=8YFLogxK

M3 - Article

VL - 119

SP - 1648

EP - 1653

JO - Endocrinology

JF - Endocrinology

SN - 0013-7227

IS - 4

ER -