TY - JOUR
T1 - Endogenous opioid systems regulate cell proliferation in the developing rat brain
AU - Zagon, Ian S.
AU - MacLaughlin, Patricia J.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1987/5/26
Y1 - 1987/5/26
N2 - The role of endogenous opioid systems in modulating the proliferation of developing cerebellar cells was examined autoradiographically in 6-day-old rats. The blockade of endogenous opioid-opioid receptor interaction by naltrexone, a potent opioid antagonist, was accompanied within 1-2 h by an increased proportion of cells incorporating [3H]thymidine. When high doses of naltrexone (50 mg/kg) were administered this index was still elevated 12 h later; however, when low doses of naltrexone (1 mg/kg) were administered the index of labeled cells was decreased markedly. Injection of methionine-enkephalin, an endogenous opioid peptide, also resulted in a decrease in the proportion of cells incorporating [3H]thymidine. Concomitant injection of 1 mg/kg naloxone, however, blocked the inhibitory effects of methionine-enkephalin on cell division but did not itself affect cell generation. These studies demonstrate that endogenous opioid systems can regulate the proliferation of cell populations in the developing nervous system and do so through an inhibitory mechanism.
AB - The role of endogenous opioid systems in modulating the proliferation of developing cerebellar cells was examined autoradiographically in 6-day-old rats. The blockade of endogenous opioid-opioid receptor interaction by naltrexone, a potent opioid antagonist, was accompanied within 1-2 h by an increased proportion of cells incorporating [3H]thymidine. When high doses of naltrexone (50 mg/kg) were administered this index was still elevated 12 h later; however, when low doses of naltrexone (1 mg/kg) were administered the index of labeled cells was decreased markedly. Injection of methionine-enkephalin, an endogenous opioid peptide, also resulted in a decrease in the proportion of cells incorporating [3H]thymidine. Concomitant injection of 1 mg/kg naloxone, however, blocked the inhibitory effects of methionine-enkephalin on cell division but did not itself affect cell generation. These studies demonstrate that endogenous opioid systems can regulate the proliferation of cell populations in the developing nervous system and do so through an inhibitory mechanism.
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U2 - 10.1016/0006-8993(87)91440-5
DO - 10.1016/0006-8993(87)91440-5
M3 - Article
C2 - 3607463
AN - SCOPUS:0023193668
SN - 0006-8993
VL - 412
SP - 68
EP - 72
JO - Brain research
JF - Brain research
IS - 1
ER -