Effects of naloxone and D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 and the protein kinase inhibitors H7 and H8 on acute morphine dependence and antinociceptive tolerance in mice

Edward J. Bilsky, Robert N. Bernstein, Zaijie Wang, Wolfgang Sadée, Frank Porreca

Research output: Contribution to journalArticle

95 Citations (Scopus)

Abstract

Previous studies measuring opioid inhibition of cyclic adenosine monophosphate in SH-SY5Y cells supported the hypothesis that continuous agonist stimulation causes a gradual conversion of the μ opioid receptor to a sensitized or constitutively active state termed μ*. Conversion to μ* was prevented by the kinase inhibitor H7, but not its close analog H8. Naloxone was proposed to act as a negative antagonist (inverse agonist) blocking μ* activity, whereas D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) appeared to act as a neutral antagonist having no effect on μ* activity. Initial in vivo results indicated that μ* activity may play a role in narcotic tolerance and dependence (Wang et al., Life Sci. 54: PL339- PL350 1994). Our study explores the pharmacology of H7 and H8, naloxone and CTAP in mice after induction of acute tolerance and dependence induced by a single s.c. dose of morphine (100 mg/kg). Physical dependence was defined by withdrawal jumping induced by i.p. naloxone injections 4 hr after the morphine dose, the time of maximal physical dependence. Neither H7 nor H8 (50 nmol or less) induced jumping, affected morphine antinociception or produced significant behavioral effects, when injected by the intracerebroventricular (i.c.v.) or intrathecal (i.th.) routes. When given 30 min before the naloxone challenge, H7, but not H8, significantly reduced naloxone jumping by i.c.v. injection. Administration of naloxone into the central nervous system, rather than by i.p. administration, required coinjection by both i.c.v. and i.th. routes to elicit full withdrawal jumping (30 nmol at each site). In contrast, the putative neutral antagonist CTAP caused little withdrawal jumping when coinjected i.c.v. and i.th., as expected if modulation of μ* activity played a role in dependence. However, CTAP was capable of partially reversing naloxone (i.p.) induced jumping when given either i.c.v. or i.th., indicating that CTAP competes with naloxone at μ*. Moreover, these results demonstrate that both spinal and supraspinal sites are required for full opioid withdrawal jumping in mice. Antinociceptive tolerance was also evaluated by determining the response to morphine in the 55°C warm-water tail-flick test. Morphine pretreatment (100 mg/kg, s.c., -5 hr) produced antinociceptive tolerance as shown by a 2.7-fold increase in the calculated morphine A50 value. Tolerance was reversed by H7, but not H8, treatment (50 nmol, i.c.v., -30 min). These results are consistent with the hypothesis that a sensitized or constitutively active μ* state plays a role in narcotic tolerance and dependence.

Original languageEnglish (US)
Pages (from-to)484-490
Number of pages7
JournalJournal of Pharmacology and Experimental Therapeutics
Volume277
Issue number1
StatePublished - Apr 1996

Fingerprint

Morphine Dependence
Naloxone
Morphine
Opioid-Related Disorders
Opioid Analgesics
Injections
CTAP octapeptide
N-(2-(methylamino)ethyl)-5-isoquinolinesulfonamide
Opioid Receptors
Cyclic AMP
Tail
Phosphotransferases
Central Nervous System
Pharmacology
Water

ASJC Scopus subject areas

  • Pharmacology

Cite this

Effects of naloxone and D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 and the protein kinase inhibitors H7 and H8 on acute morphine dependence and antinociceptive tolerance in mice. / Bilsky, Edward J.; Bernstein, Robert N.; Wang, Zaijie; Sadée, Wolfgang; Porreca, Frank.

In: Journal of Pharmacology and Experimental Therapeutics, Vol. 277, No. 1, 04.1996, p. 484-490.

Research output: Contribution to journalArticle

@article{82a6d42a148a4c58970e9206c26a7216,
title = "Effects of naloxone and D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 and the protein kinase inhibitors H7 and H8 on acute morphine dependence and antinociceptive tolerance in mice",
abstract = "Previous studies measuring opioid inhibition of cyclic adenosine monophosphate in SH-SY5Y cells supported the hypothesis that continuous agonist stimulation causes a gradual conversion of the μ opioid receptor to a sensitized or constitutively active state termed μ*. Conversion to μ* was prevented by the kinase inhibitor H7, but not its close analog H8. Naloxone was proposed to act as a negative antagonist (inverse agonist) blocking μ* activity, whereas D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) appeared to act as a neutral antagonist having no effect on μ* activity. Initial in vivo results indicated that μ* activity may play a role in narcotic tolerance and dependence (Wang et al., Life Sci. 54: PL339- PL350 1994). Our study explores the pharmacology of H7 and H8, naloxone and CTAP in mice after induction of acute tolerance and dependence induced by a single s.c. dose of morphine (100 mg/kg). Physical dependence was defined by withdrawal jumping induced by i.p. naloxone injections 4 hr after the morphine dose, the time of maximal physical dependence. Neither H7 nor H8 (50 nmol or less) induced jumping, affected morphine antinociception or produced significant behavioral effects, when injected by the intracerebroventricular (i.c.v.) or intrathecal (i.th.) routes. When given 30 min before the naloxone challenge, H7, but not H8, significantly reduced naloxone jumping by i.c.v. injection. Administration of naloxone into the central nervous system, rather than by i.p. administration, required coinjection by both i.c.v. and i.th. routes to elicit full withdrawal jumping (30 nmol at each site). In contrast, the putative neutral antagonist CTAP caused little withdrawal jumping when coinjected i.c.v. and i.th., as expected if modulation of μ* activity played a role in dependence. However, CTAP was capable of partially reversing naloxone (i.p.) induced jumping when given either i.c.v. or i.th., indicating that CTAP competes with naloxone at μ*. Moreover, these results demonstrate that both spinal and supraspinal sites are required for full opioid withdrawal jumping in mice. Antinociceptive tolerance was also evaluated by determining the response to morphine in the 55°C warm-water tail-flick test. Morphine pretreatment (100 mg/kg, s.c., -5 hr) produced antinociceptive tolerance as shown by a 2.7-fold increase in the calculated morphine A50 value. Tolerance was reversed by H7, but not H8, treatment (50 nmol, i.c.v., -30 min). These results are consistent with the hypothesis that a sensitized or constitutively active μ* state plays a role in narcotic tolerance and dependence.",
author = "Bilsky, {Edward J.} and Bernstein, {Robert N.} and Zaijie Wang and Wolfgang Sad{\'e}e and Frank Porreca",
year = "1996",
month = "4",
language = "English (US)",
volume = "277",
pages = "484--490",
journal = "Journal of Pharmacology and Experimental Therapeutics",
issn = "0022-3565",
publisher = "American Society for Pharmacology and Experimental Therapeutics",
number = "1",

}

TY - JOUR

T1 - Effects of naloxone and D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 and the protein kinase inhibitors H7 and H8 on acute morphine dependence and antinociceptive tolerance in mice

AU - Bilsky, Edward J.

AU - Bernstein, Robert N.

AU - Wang, Zaijie

AU - Sadée, Wolfgang

AU - Porreca, Frank

PY - 1996/4

Y1 - 1996/4

N2 - Previous studies measuring opioid inhibition of cyclic adenosine monophosphate in SH-SY5Y cells supported the hypothesis that continuous agonist stimulation causes a gradual conversion of the μ opioid receptor to a sensitized or constitutively active state termed μ*. Conversion to μ* was prevented by the kinase inhibitor H7, but not its close analog H8. Naloxone was proposed to act as a negative antagonist (inverse agonist) blocking μ* activity, whereas D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) appeared to act as a neutral antagonist having no effect on μ* activity. Initial in vivo results indicated that μ* activity may play a role in narcotic tolerance and dependence (Wang et al., Life Sci. 54: PL339- PL350 1994). Our study explores the pharmacology of H7 and H8, naloxone and CTAP in mice after induction of acute tolerance and dependence induced by a single s.c. dose of morphine (100 mg/kg). Physical dependence was defined by withdrawal jumping induced by i.p. naloxone injections 4 hr after the morphine dose, the time of maximal physical dependence. Neither H7 nor H8 (50 nmol or less) induced jumping, affected morphine antinociception or produced significant behavioral effects, when injected by the intracerebroventricular (i.c.v.) or intrathecal (i.th.) routes. When given 30 min before the naloxone challenge, H7, but not H8, significantly reduced naloxone jumping by i.c.v. injection. Administration of naloxone into the central nervous system, rather than by i.p. administration, required coinjection by both i.c.v. and i.th. routes to elicit full withdrawal jumping (30 nmol at each site). In contrast, the putative neutral antagonist CTAP caused little withdrawal jumping when coinjected i.c.v. and i.th., as expected if modulation of μ* activity played a role in dependence. However, CTAP was capable of partially reversing naloxone (i.p.) induced jumping when given either i.c.v. or i.th., indicating that CTAP competes with naloxone at μ*. Moreover, these results demonstrate that both spinal and supraspinal sites are required for full opioid withdrawal jumping in mice. Antinociceptive tolerance was also evaluated by determining the response to morphine in the 55°C warm-water tail-flick test. Morphine pretreatment (100 mg/kg, s.c., -5 hr) produced antinociceptive tolerance as shown by a 2.7-fold increase in the calculated morphine A50 value. Tolerance was reversed by H7, but not H8, treatment (50 nmol, i.c.v., -30 min). These results are consistent with the hypothesis that a sensitized or constitutively active μ* state plays a role in narcotic tolerance and dependence.

AB - Previous studies measuring opioid inhibition of cyclic adenosine monophosphate in SH-SY5Y cells supported the hypothesis that continuous agonist stimulation causes a gradual conversion of the μ opioid receptor to a sensitized or constitutively active state termed μ*. Conversion to μ* was prevented by the kinase inhibitor H7, but not its close analog H8. Naloxone was proposed to act as a negative antagonist (inverse agonist) blocking μ* activity, whereas D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) appeared to act as a neutral antagonist having no effect on μ* activity. Initial in vivo results indicated that μ* activity may play a role in narcotic tolerance and dependence (Wang et al., Life Sci. 54: PL339- PL350 1994). Our study explores the pharmacology of H7 and H8, naloxone and CTAP in mice after induction of acute tolerance and dependence induced by a single s.c. dose of morphine (100 mg/kg). Physical dependence was defined by withdrawal jumping induced by i.p. naloxone injections 4 hr after the morphine dose, the time of maximal physical dependence. Neither H7 nor H8 (50 nmol or less) induced jumping, affected morphine antinociception or produced significant behavioral effects, when injected by the intracerebroventricular (i.c.v.) or intrathecal (i.th.) routes. When given 30 min before the naloxone challenge, H7, but not H8, significantly reduced naloxone jumping by i.c.v. injection. Administration of naloxone into the central nervous system, rather than by i.p. administration, required coinjection by both i.c.v. and i.th. routes to elicit full withdrawal jumping (30 nmol at each site). In contrast, the putative neutral antagonist CTAP caused little withdrawal jumping when coinjected i.c.v. and i.th., as expected if modulation of μ* activity played a role in dependence. However, CTAP was capable of partially reversing naloxone (i.p.) induced jumping when given either i.c.v. or i.th., indicating that CTAP competes with naloxone at μ*. Moreover, these results demonstrate that both spinal and supraspinal sites are required for full opioid withdrawal jumping in mice. Antinociceptive tolerance was also evaluated by determining the response to morphine in the 55°C warm-water tail-flick test. Morphine pretreatment (100 mg/kg, s.c., -5 hr) produced antinociceptive tolerance as shown by a 2.7-fold increase in the calculated morphine A50 value. Tolerance was reversed by H7, but not H8, treatment (50 nmol, i.c.v., -30 min). These results are consistent with the hypothesis that a sensitized or constitutively active μ* state plays a role in narcotic tolerance and dependence.

UR - http://www.scopus.com/inward/record.url?scp=0030439407&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030439407&partnerID=8YFLogxK

M3 - Article

VL - 277

SP - 484

EP - 490

JO - Journal of Pharmacology and Experimental Therapeutics

JF - Journal of Pharmacology and Experimental Therapeutics

SN - 0022-3565

IS - 1

ER -