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.
Das
S
S
Matwyshyn
G A
GA
Bhargava
H N
HN
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