Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats

Hiroshi Itoh, K. Nakao, T. Yamada, N. Morii, S. Shiono, M. Sakamoto, A. Sugawara, Y. Saito, M. Mukoyama, H. Arai, H. Imura

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

To investigate the role of leumorphin, a κ-opioid agonist derived from proenkephalin B (neoendorphin/dynorphin precursor) in the central cardiovascular control, the effects of intracerebroventricular (ICV) administration of leumorphin on basal blood pressure and angiotensin II (AII)-stimulated pressor response were examined in conscious unrestrained rats. The ICV injection of 0.06 and 0.6 nmol of leumorphin caused a significant decrease in basal blood pressure (Δ mean arterial pressure (MAP): -6.5 ± 2.7 and -7.2 ± 1.7 mm Hg, respectively). The ICV injection of AII (0.1 nmol) elicited a pressor response (ΔMAP: 21.4 ± 1.1 mm Hg). This pressor response was significantly reduced by the simultaneous administration of leumorphin, and furthermore, the blood pressure was lowered below the basal level. These depressor actions of leumorphin were partially antagonized by the preadministration of naloxone, an opiate antagonist. These results together with our previous works on the potent inhibitory actions of leumorphin on drinking and vasopressin secretion suggest the possible involvement of leumorphin in the central regulation of blood pressure and body fluid homeostasis.

Original languageEnglish
Pages (from-to)256-261
Number of pages6
JournalAmerican Journal of Hypertension
Volume1
Issue number3 I
Publication statusPublished - 1988
Externally publishedYes

Fingerprint

Opioid Analgesics
Blood Pressure
Angiotensin II
Opiate Alkaloids
Arterial Pressure
Dynorphins
Injections
Body Fluids
Naloxone
preproenkephalin
Vasopressins
Drinking
Homeostasis

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Itoh, H., Nakao, K., Yamada, T., Morii, N., Shiono, S., Sakamoto, M., ... Imura, H. (1988). Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats. American Journal of Hypertension, 1(3 I), 256-261.

Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats. / Itoh, Hiroshi; Nakao, K.; Yamada, T.; Morii, N.; Shiono, S.; Sakamoto, M.; Sugawara, A.; Saito, Y.; Mukoyama, M.; Arai, H.; Imura, H.

In: American Journal of Hypertension, Vol. 1, No. 3 I, 1988, p. 256-261.

Research output: Contribution to journalArticle

Itoh, H, Nakao, K, Yamada, T, Morii, N, Shiono, S, Sakamoto, M, Sugawara, A, Saito, Y, Mukoyama, M, Arai, H & Imura, H 1988, 'Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats', American Journal of Hypertension, vol. 1, no. 3 I, pp. 256-261.
Itoh H, Nakao K, Yamada T, Morii N, Shiono S, Sakamoto M et al. Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats. American Journal of Hypertension. 1988;1(3 I):256-261.
Itoh, Hiroshi ; Nakao, K. ; Yamada, T. ; Morii, N. ; Shiono, S. ; Sakamoto, M. ; Sugawara, A. ; Saito, Y. ; Mukoyama, M. ; Arai, H. ; Imura, H. / Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats. In: American Journal of Hypertension. 1988 ; Vol. 1, No. 3 I. pp. 256-261.
@article{44b800e504a74044b6fbd3ecf12293c5,
title = "Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats",
abstract = "To investigate the role of leumorphin, a κ-opioid agonist derived from proenkephalin B (neoendorphin/dynorphin precursor) in the central cardiovascular control, the effects of intracerebroventricular (ICV) administration of leumorphin on basal blood pressure and angiotensin II (AII)-stimulated pressor response were examined in conscious unrestrained rats. The ICV injection of 0.06 and 0.6 nmol of leumorphin caused a significant decrease in basal blood pressure (Δ mean arterial pressure (MAP): -6.5 ± 2.7 and -7.2 ± 1.7 mm Hg, respectively). The ICV injection of AII (0.1 nmol) elicited a pressor response (ΔMAP: 21.4 ± 1.1 mm Hg). This pressor response was significantly reduced by the simultaneous administration of leumorphin, and furthermore, the blood pressure was lowered below the basal level. These depressor actions of leumorphin were partially antagonized by the preadministration of naloxone, an opiate antagonist. These results together with our previous works on the potent inhibitory actions of leumorphin on drinking and vasopressin secretion suggest the possible involvement of leumorphin in the central regulation of blood pressure and body fluid homeostasis.",
author = "Hiroshi Itoh and K. Nakao and T. Yamada and N. Morii and S. Shiono and M. Sakamoto and A. Sugawara and Y. Saito and M. Mukoyama and H. Arai and H. Imura",
year = "1988",
language = "English",
volume = "1",
pages = "256--261",
journal = "American Journal of Hypertension",
issn = "0895-7061",
publisher = "Oxford University Press",
number = "3 I",

}

TY - JOUR

T1 - Potent depressor action of leumorphin, a κ-opioid agonist, in conscious rats

AU - Itoh, Hiroshi

AU - Nakao, K.

AU - Yamada, T.

AU - Morii, N.

AU - Shiono, S.

AU - Sakamoto, M.

AU - Sugawara, A.

AU - Saito, Y.

AU - Mukoyama, M.

AU - Arai, H.

AU - Imura, H.

PY - 1988

Y1 - 1988

N2 - To investigate the role of leumorphin, a κ-opioid agonist derived from proenkephalin B (neoendorphin/dynorphin precursor) in the central cardiovascular control, the effects of intracerebroventricular (ICV) administration of leumorphin on basal blood pressure and angiotensin II (AII)-stimulated pressor response were examined in conscious unrestrained rats. The ICV injection of 0.06 and 0.6 nmol of leumorphin caused a significant decrease in basal blood pressure (Δ mean arterial pressure (MAP): -6.5 ± 2.7 and -7.2 ± 1.7 mm Hg, respectively). The ICV injection of AII (0.1 nmol) elicited a pressor response (ΔMAP: 21.4 ± 1.1 mm Hg). This pressor response was significantly reduced by the simultaneous administration of leumorphin, and furthermore, the blood pressure was lowered below the basal level. These depressor actions of leumorphin were partially antagonized by the preadministration of naloxone, an opiate antagonist. These results together with our previous works on the potent inhibitory actions of leumorphin on drinking and vasopressin secretion suggest the possible involvement of leumorphin in the central regulation of blood pressure and body fluid homeostasis.

AB - To investigate the role of leumorphin, a κ-opioid agonist derived from proenkephalin B (neoendorphin/dynorphin precursor) in the central cardiovascular control, the effects of intracerebroventricular (ICV) administration of leumorphin on basal blood pressure and angiotensin II (AII)-stimulated pressor response were examined in conscious unrestrained rats. The ICV injection of 0.06 and 0.6 nmol of leumorphin caused a significant decrease in basal blood pressure (Δ mean arterial pressure (MAP): -6.5 ± 2.7 and -7.2 ± 1.7 mm Hg, respectively). The ICV injection of AII (0.1 nmol) elicited a pressor response (ΔMAP: 21.4 ± 1.1 mm Hg). This pressor response was significantly reduced by the simultaneous administration of leumorphin, and furthermore, the blood pressure was lowered below the basal level. These depressor actions of leumorphin were partially antagonized by the preadministration of naloxone, an opiate antagonist. These results together with our previous works on the potent inhibitory actions of leumorphin on drinking and vasopressin secretion suggest the possible involvement of leumorphin in the central regulation of blood pressure and body fluid homeostasis.

UR - http://www.scopus.com/inward/record.url?scp=0023934305&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023934305&partnerID=8YFLogxK

M3 - Article

C2 - 2839205

AN - SCOPUS:0023934305

VL - 1

SP - 256

EP - 261

JO - American Journal of Hypertension

JF - American Journal of Hypertension

SN - 0895-7061

IS - 3 I

ER -