A novel response to propranolol: Contractile response in the isolated rabbit ear artery

Donald W. Ashbrook, Ralph E. Purdy, Diana E. Hurlbut, Leslie A. Rains, John P. Reidy, Robert Stratford Jr.

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Propranolol caused a contractile response in the isolated rabbit ear artery (EA). The concentration of propranolol causing a threshold contraction was 1.76 × 10-6M while that causing a maximal contraction of 2.2 ± 0.18 g was 3 × 10-5M. Higher concentrations caused tissue relaxation. Phentolamine, 10-7 and 10-6M reduced the propranolol-induced contractions by 50% and 90%, respectively while prazosin, 10-8, 10-7 and 10-6M caused reductions of 54, 74 and 88%, respectively. Reserpinization of the rabbit with 5 mg/kg 24 hours before use eliminated the EA contractile response to tyramine but had no effect on that to propranolol. Desmethylimipramine plus deoxycorticosterone acetate enhanced the submaximal contraction of the EA to propranolol. In vitro denervation with 6-hydroxydopamine (6-OHDA) decreased the response of the EA to tyramine and propranolol by 96% and 85% respectively but increased that to norepinephrine (NE) by 11%. Rabbit thoracic aorta (TA) did not respond to propranolol. In EA contracted with vasopressin o or 30 mM potassium, propranolol 10-4 and 3 × 10-4M caused a 20% and 100% relaxation, respectively. It is concluded that propranolol elicits a contractile response in the EA, at least in part, by direct activation of postsynaptic alpha adrenoceptors.

Original languageEnglish (US)
Pages (from-to)155-163
Number of pages9
JournalLife Sciences
Volume26
Issue number2
DOIs
StatePublished - Jan 14 1980
Externally publishedYes

Fingerprint

Propranolol
Ear
Arteries
Rabbits
Tyramine
Oxidopamine
Desoxycorticosterone
Desipramine
Prazosin
Phentolamine
Denervation
Vasopressins
Thoracic Aorta
Adrenergic Receptors
Norepinephrine
Potassium
Acetates
Chemical activation
Tissue

ASJC Scopus subject areas

  • Pharmacology

Cite this

A novel response to propranolol : Contractile response in the isolated rabbit ear artery. / Ashbrook, Donald W.; Purdy, Ralph E.; Hurlbut, Diana E.; Rains, Leslie A.; Reidy, John P.; Stratford Jr., Robert.

In: Life Sciences, Vol. 26, No. 2, 14.01.1980, p. 155-163.

Research output: Contribution to journalArticle

Ashbrook, Donald W. ; Purdy, Ralph E. ; Hurlbut, Diana E. ; Rains, Leslie A. ; Reidy, John P. ; Stratford Jr., Robert. / A novel response to propranolol : Contractile response in the isolated rabbit ear artery. In: Life Sciences. 1980 ; Vol. 26, No. 2. pp. 155-163.
@article{7b2ae5e6eda74a1ebc720b69de1f79b7,
title = "A novel response to propranolol: Contractile response in the isolated rabbit ear artery",
abstract = "Propranolol caused a contractile response in the isolated rabbit ear artery (EA). The concentration of propranolol causing a threshold contraction was 1.76 × 10-6M while that causing a maximal contraction of 2.2 ± 0.18 g was 3 × 10-5M. Higher concentrations caused tissue relaxation. Phentolamine, 10-7 and 10-6M reduced the propranolol-induced contractions by 50{\%} and 90{\%}, respectively while prazosin, 10-8, 10-7 and 10-6M caused reductions of 54, 74 and 88{\%}, respectively. Reserpinization of the rabbit with 5 mg/kg 24 hours before use eliminated the EA contractile response to tyramine but had no effect on that to propranolol. Desmethylimipramine plus deoxycorticosterone acetate enhanced the submaximal contraction of the EA to propranolol. In vitro denervation with 6-hydroxydopamine (6-OHDA) decreased the response of the EA to tyramine and propranolol by 96{\%} and 85{\%} respectively but increased that to norepinephrine (NE) by 11{\%}. Rabbit thoracic aorta (TA) did not respond to propranolol. In EA contracted with vasopressin o or 30 mM potassium, propranolol 10-4 and 3 × 10-4M caused a 20{\%} and 100{\%} relaxation, respectively. It is concluded that propranolol elicits a contractile response in the EA, at least in part, by direct activation of postsynaptic alpha adrenoceptors.",
author = "Ashbrook, {Donald W.} and Purdy, {Ralph E.} and Hurlbut, {Diana E.} and Rains, {Leslie A.} and Reidy, {John P.} and {Stratford Jr.}, Robert",
year = "1980",
month = "1",
day = "14",
doi = "10.1016/0024-3205(80)90060-0",
language = "English (US)",
volume = "26",
pages = "155--163",
journal = "Life Sciences",
issn = "0024-3205",
publisher = "Elsevier Inc.",
number = "2",

}

TY - JOUR

T1 - A novel response to propranolol

T2 - Contractile response in the isolated rabbit ear artery

AU - Ashbrook, Donald W.

AU - Purdy, Ralph E.

AU - Hurlbut, Diana E.

AU - Rains, Leslie A.

AU - Reidy, John P.

AU - Stratford Jr., Robert

PY - 1980/1/14

Y1 - 1980/1/14

N2 - Propranolol caused a contractile response in the isolated rabbit ear artery (EA). The concentration of propranolol causing a threshold contraction was 1.76 × 10-6M while that causing a maximal contraction of 2.2 ± 0.18 g was 3 × 10-5M. Higher concentrations caused tissue relaxation. Phentolamine, 10-7 and 10-6M reduced the propranolol-induced contractions by 50% and 90%, respectively while prazosin, 10-8, 10-7 and 10-6M caused reductions of 54, 74 and 88%, respectively. Reserpinization of the rabbit with 5 mg/kg 24 hours before use eliminated the EA contractile response to tyramine but had no effect on that to propranolol. Desmethylimipramine plus deoxycorticosterone acetate enhanced the submaximal contraction of the EA to propranolol. In vitro denervation with 6-hydroxydopamine (6-OHDA) decreased the response of the EA to tyramine and propranolol by 96% and 85% respectively but increased that to norepinephrine (NE) by 11%. Rabbit thoracic aorta (TA) did not respond to propranolol. In EA contracted with vasopressin o or 30 mM potassium, propranolol 10-4 and 3 × 10-4M caused a 20% and 100% relaxation, respectively. It is concluded that propranolol elicits a contractile response in the EA, at least in part, by direct activation of postsynaptic alpha adrenoceptors.

AB - Propranolol caused a contractile response in the isolated rabbit ear artery (EA). The concentration of propranolol causing a threshold contraction was 1.76 × 10-6M while that causing a maximal contraction of 2.2 ± 0.18 g was 3 × 10-5M. Higher concentrations caused tissue relaxation. Phentolamine, 10-7 and 10-6M reduced the propranolol-induced contractions by 50% and 90%, respectively while prazosin, 10-8, 10-7 and 10-6M caused reductions of 54, 74 and 88%, respectively. Reserpinization of the rabbit with 5 mg/kg 24 hours before use eliminated the EA contractile response to tyramine but had no effect on that to propranolol. Desmethylimipramine plus deoxycorticosterone acetate enhanced the submaximal contraction of the EA to propranolol. In vitro denervation with 6-hydroxydopamine (6-OHDA) decreased the response of the EA to tyramine and propranolol by 96% and 85% respectively but increased that to norepinephrine (NE) by 11%. Rabbit thoracic aorta (TA) did not respond to propranolol. In EA contracted with vasopressin o or 30 mM potassium, propranolol 10-4 and 3 × 10-4M caused a 20% and 100% relaxation, respectively. It is concluded that propranolol elicits a contractile response in the EA, at least in part, by direct activation of postsynaptic alpha adrenoceptors.

UR - http://www.scopus.com/inward/record.url?scp=0018874376&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018874376&partnerID=8YFLogxK

U2 - 10.1016/0024-3205(80)90060-0

DO - 10.1016/0024-3205(80)90060-0

M3 - Article

C2 - 7366323

AN - SCOPUS:0018874376

VL - 26

SP - 155

EP - 163

JO - Life Sciences

JF - Life Sciences

SN - 0024-3205

IS - 2

ER -