Coupling of signals to brown fat: α and β adrenergic responses in intact rats

K. E. Flaim, Barbara A Horwitz, J. M. Horowitz

Research output: Chapter in Book/Report/Conference proceedingChapter

57 Citations (Scopus)

Abstract

The present study examines the effects of α- and β-adrenergic antagonists (phentolamine and propranolol, respectively) and agonists (phenylephrine, isoproterenol) on the neurally induced temperature changes and membrane potentials of interscapular brown adipocytes. These studies, performed in vivo with anesthetized rats, indicate that both α- and β-adrenergic components are associated with the biphasic temperature changes observed following sympathetic activation of the tissue. Specifically, the initial transient temperature decrease seen after brown fat stimulation appeared to reflect vasoconstriction mediated primarily via α-receptors, while the subsequent rise in tissue temperature was associated primarily (though perhaps not entirely) with β-adrenergic pathways. In contrast, the redistribution of ions across the membrane of the brown adipocyte, a phenomenon manifested as a membrane depolarization, was elicited by phenylephrine (an α-agonist) as well as by isoproterenol (a β-agonist), with the magnitude of the isoproterenol-induced depolarization being comparable to that of the phenylephrine-induced effect.

Original languageEnglish (US)
Title of host publicationAmerican Journal of Physiology
Volume232
Edition2
StatePublished - 1977

Fingerprint

Brown Adipose Tissue
Adrenergic Agents
Phenylephrine
Isoproterenol
Brown Adipocytes
Temperature
Adrenergic Antagonists
Membranes
Phentolamine
Vasoconstriction
Propranolol
Membrane Potentials
Ions

ASJC Scopus subject areas

  • Medicine(all)

Cite this

Flaim, K. E., Horwitz, B. A., & Horowitz, J. M. (1977). Coupling of signals to brown fat: α and β adrenergic responses in intact rats. In American Journal of Physiology (2 ed., Vol. 232)

Coupling of signals to brown fat : α and β adrenergic responses in intact rats. / Flaim, K. E.; Horwitz, Barbara A; Horowitz, J. M.

American Journal of Physiology. Vol. 232 2. ed. 1977.

Research output: Chapter in Book/Report/Conference proceedingChapter

Flaim, KE, Horwitz, BA & Horowitz, JM 1977, Coupling of signals to brown fat: α and β adrenergic responses in intact rats. in American Journal of Physiology. 2 edn, vol. 232.
Flaim KE, Horwitz BA, Horowitz JM. Coupling of signals to brown fat: α and β adrenergic responses in intact rats. In American Journal of Physiology. 2 ed. Vol. 232. 1977
Flaim, K. E. ; Horwitz, Barbara A ; Horowitz, J. M. / Coupling of signals to brown fat : α and β adrenergic responses in intact rats. American Journal of Physiology. Vol. 232 2. ed. 1977.
@inbook{16b7ec098147489fb153ff0786dff9d8,
title = "Coupling of signals to brown fat: α and β adrenergic responses in intact rats",
abstract = "The present study examines the effects of α- and β-adrenergic antagonists (phentolamine and propranolol, respectively) and agonists (phenylephrine, isoproterenol) on the neurally induced temperature changes and membrane potentials of interscapular brown adipocytes. These studies, performed in vivo with anesthetized rats, indicate that both α- and β-adrenergic components are associated with the biphasic temperature changes observed following sympathetic activation of the tissue. Specifically, the initial transient temperature decrease seen after brown fat stimulation appeared to reflect vasoconstriction mediated primarily via α-receptors, while the subsequent rise in tissue temperature was associated primarily (though perhaps not entirely) with β-adrenergic pathways. In contrast, the redistribution of ions across the membrane of the brown adipocyte, a phenomenon manifested as a membrane depolarization, was elicited by phenylephrine (an α-agonist) as well as by isoproterenol (a β-agonist), with the magnitude of the isoproterenol-induced depolarization being comparable to that of the phenylephrine-induced effect.",
author = "Flaim, {K. E.} and Horwitz, {Barbara A} and Horowitz, {J. M.}",
year = "1977",
language = "English (US)",
volume = "232",
booktitle = "American Journal of Physiology",
edition = "2",

}

TY - CHAP

T1 - Coupling of signals to brown fat

T2 - α and β adrenergic responses in intact rats

AU - Flaim, K. E.

AU - Horwitz, Barbara A

AU - Horowitz, J. M.

PY - 1977

Y1 - 1977

N2 - The present study examines the effects of α- and β-adrenergic antagonists (phentolamine and propranolol, respectively) and agonists (phenylephrine, isoproterenol) on the neurally induced temperature changes and membrane potentials of interscapular brown adipocytes. These studies, performed in vivo with anesthetized rats, indicate that both α- and β-adrenergic components are associated with the biphasic temperature changes observed following sympathetic activation of the tissue. Specifically, the initial transient temperature decrease seen after brown fat stimulation appeared to reflect vasoconstriction mediated primarily via α-receptors, while the subsequent rise in tissue temperature was associated primarily (though perhaps not entirely) with β-adrenergic pathways. In contrast, the redistribution of ions across the membrane of the brown adipocyte, a phenomenon manifested as a membrane depolarization, was elicited by phenylephrine (an α-agonist) as well as by isoproterenol (a β-agonist), with the magnitude of the isoproterenol-induced depolarization being comparable to that of the phenylephrine-induced effect.

AB - The present study examines the effects of α- and β-adrenergic antagonists (phentolamine and propranolol, respectively) and agonists (phenylephrine, isoproterenol) on the neurally induced temperature changes and membrane potentials of interscapular brown adipocytes. These studies, performed in vivo with anesthetized rats, indicate that both α- and β-adrenergic components are associated with the biphasic temperature changes observed following sympathetic activation of the tissue. Specifically, the initial transient temperature decrease seen after brown fat stimulation appeared to reflect vasoconstriction mediated primarily via α-receptors, while the subsequent rise in tissue temperature was associated primarily (though perhaps not entirely) with β-adrenergic pathways. In contrast, the redistribution of ions across the membrane of the brown adipocyte, a phenomenon manifested as a membrane depolarization, was elicited by phenylephrine (an α-agonist) as well as by isoproterenol (a β-agonist), with the magnitude of the isoproterenol-induced depolarization being comparable to that of the phenylephrine-induced effect.

UR - http://www.scopus.com/inward/record.url?scp=0017359803&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0017359803&partnerID=8YFLogxK

M3 - Chapter

C2 - 842692

AN - SCOPUS:0017359803

VL - 232

BT - American Journal of Physiology

ER -