PMID- 2824958
OWN - NLM
STAT- MEDLINE
DCOM- 19871228
LR  - 20190701
IS  - 0024-3205 (Print)
IS  - 0024-3205 (Linking)
VI  - 41
IP  - 23
DP  - 1987 Dec 7
TI  - Differential antagonism of mu agonists by U50,488H in the rat.
PG  - 2511-6
AB  - Agonist, and antagonist effects of the proposed kappa opioid agonist, U50,488H 
      (U50) have been studied in an experimental model of seizure activity 
      (flurothyl-induced seizure threshold) (ST) and in the central modulation of 
      spontaneous, volume-induced micturition contractions (bladder motility) (BM) in 
      rats. Intracerebroventricular (i.c.v.) administration of U50 (at the doses 
      tested) did not produce any agonist effect in either ST or in BM. In contrast, 
      i.c.v. administration of [D-Ala2, NMPhe4, Gly-ol]enkephalin (DAGO) or etorphine, 
      agonists with activity at mu opioid receptors, produced an elevation of ST and 
      inhibition of BM. The elevation in ST produced by etorphine (0.004 nmol) was 
      prevented by prior treatment with U50. In contrast, the approximately 
      equieffective elevation in ST resulting from DAGO was not affected by U50 
      pretreatment. Similarly, pretreatment of rats with U50 antagonized the 
      approximately equieffective BM effects of etorphine, but not those of DAGO. As 
      both DAGO and etorphine are thought to exert their effects via the opiate mu 
      receptor, the results may be consistent with the view that subpopulations of mu 
      receptors exist within the central nervous system; these sites may be 
      differentially associated with the kappa receptor.
FAU - Porreca, F
AU  - Porreca F
AD  - Department of Pharmacology, University of Arizona Health Sciences Center, Tucson 
      85724.
FAU - Tortella, F C
AU  - Tortella FC
LA  - eng
GR  - DK 36289/DK/NIDDK NIH HHS/United States
GR  - NS 23710/NS/NINDS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - Life Sci
JT  - Life sciences
JID - 0375521
RN  - 0 (Enkephalins)
RN  - 0 (Pyrrolidines)
RN  - 0 (Receptors, Opioid)
RN  - 0 (Receptors, Opioid, kappa)
RN  - 0 (Receptors, Opioid, mu)
RN  - 100929-53-1 (Enkephalin, Ala(2)-MePhe(4)-Gly(5)-)
RN  - 42M2Y6NU9O (Etorphine)
RN  - 67198-13-4 
      (3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, 
      (trans)-Isomer)
SB  - IM
MH  - 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, 
      (trans)-Isomer
MH  - Animals
MH  - Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
MH  - Enkephalins/pharmacology
MH  - Etorphine/pharmacology
MH  - Female
MH  - Male
MH  - Muscle Contraction/drug effects
MH  - Muscle, Smooth/drug effects
MH  - Pyrrolidines/*pharmacology
MH  - Rats
MH  - Rats, Inbred Strains
MH  - Receptors, Opioid/*drug effects
MH  - Receptors, Opioid, kappa
MH  - Receptors, Opioid, mu
MH  - Seizures/chemically induced
MH  - Urinary Bladder
EDAT- 1987/12/07 00:00
MHDA- 1987/12/07 00:01
CRDT- 1987/12/07 00:00
PHST- 1987/12/07 00:00 [pubmed]
PHST- 1987/12/07 00:01 [medline]
PHST- 1987/12/07 00:00 [entrez]
AID - 0024-3205(87)90435-8 [pii]
AID - 10.1016/0024-3205(87)90435-8 [doi]
PST - ppublish
SO  - Life Sci. 1987 Dec 7;41(23):2511-6. doi: 10.1016/0024-3205(87)90435-8.