Effect of acute and chronic morphine administration on brain cholinergic muscarinic receptors.
The binding of [3H]quinuclidinyl benzilate (QNB) to various brain regions was determined in rats after acute or chronic treatment with morphine. Morphine and naloxone, in vitro, inhibited the binding of [3H]QNB to striatal membranes only at high concentrations. Thirty minutes after a single injection, morphine (5 or 40 mg/kg s.c.) did not alter the Bmax or Kd values for [3H]QNB binding to striatal receptors. The binding of [3H]QNB to membranes of different brain regions was not changed in morphine tolerant-dependent rats or rats undergoing abrupt or naloxone precipitated withdrawal. The results suggest that central cholinergic muscarinic receptors are unaffected by acute or chronic treatment with morphine, or during abstinence.
S
S
Das
G A
GA
Matwyshyn
H N
HN
Bhargava
D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects*; D003342:Corpus Striatum / Q000378:metabolism; D004343:Drug Implants; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009021:Morphine Dependence / Q000503:physiopathology; D009270:Naloxone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011976:Receptors, Muscarinic / Q000187:drug effects*; D013375:Substance Withdrawal Syndrome / Q000378:metabolism
D004343:Drug Implants; D011976:Receptors, Muscarinic; D009270:Naloxone; D009020:Morphine