TY - JOUR
T1 - Opposing effects of morphine and the neurotrophins, NT-3, NT-4, and BDNF, on locus coeruleus neurons in vitro
AU - Sldair-Tavron, Liora
AU - Nestler, Eric J.
N1 - Funding Information:
We thank Drs. Ronald Lindsay and Stanley Wiegand for providing the neurotrophins used in this study. This work was supported by U.S.P.H.S. Grants DA08227 and DA00203, and by tl~e Abraham Ribicoff Research Facilities of the Connecticut Mental Health Center, State of Connecticut, Department of Mental Health.
PY - 1995/12/8
Y1 - 1995/12/8
N2 - The development of noradrenergic locus coeruleus (LC) neurons is subject to regulation by multiple epigenetic signals. To examine the potential regulation of LC ontogeny by opiates and neurotrophins, we studied the effects of morphine and NT-3, NT-4, and BDNF on the survival and differentiation of LC neurons from prenatal rats in dissociated cell culture. Noradrenergic cells were identified and counted following tyrosine hydroxylase (TH) immunocytochemistry, and their state of differentiation was assessed by measuring norepinephrine (NE) uptake. Treating LC cultures with morphine starting on day 1 after plating resulted in a 20% decrease in NE uptake and a small (12%) but significant decrease in the number of TH-immunoreactive (TH + ) cells. Application of morphine on day 4 after plating had the same effect on NE uptake without influencing TH + cell number. This effect of morphine was blocked by concomitant exposure to naloxone (an opioid receptor antagonist), and mimicked by exposure to opioid peptides. Treatment of cultures with the neurotrophins, NT-3 or NT-4, increased NE uptake and TH + cell number, as reported previously. Moreover, we show for the first time that brain-derived neurotrophic factor (BDNF) exerts similar effects, with a large (110%) increase in NE uptake and a modest (20%) increase in TH + cell number. Cotreatment of LC cultures with morphine and NT-3 resulted in an attenuation of the NT-3 effect on both NE uptake and the number of TH + cells. In contrast, cotreatment of LC cultures with morphine and NT-4 or BDNF attenuated the neurotrophin effect on TH + cell number but not on NE uptake. Our results raise the possibility that opioid peptides may modulate the influence of neurotrophins on LC neuronal survival and differentiation.
AB - The development of noradrenergic locus coeruleus (LC) neurons is subject to regulation by multiple epigenetic signals. To examine the potential regulation of LC ontogeny by opiates and neurotrophins, we studied the effects of morphine and NT-3, NT-4, and BDNF on the survival and differentiation of LC neurons from prenatal rats in dissociated cell culture. Noradrenergic cells were identified and counted following tyrosine hydroxylase (TH) immunocytochemistry, and their state of differentiation was assessed by measuring norepinephrine (NE) uptake. Treating LC cultures with morphine starting on day 1 after plating resulted in a 20% decrease in NE uptake and a small (12%) but significant decrease in the number of TH-immunoreactive (TH + ) cells. Application of morphine on day 4 after plating had the same effect on NE uptake without influencing TH + cell number. This effect of morphine was blocked by concomitant exposure to naloxone (an opioid receptor antagonist), and mimicked by exposure to opioid peptides. Treatment of cultures with the neurotrophins, NT-3 or NT-4, increased NE uptake and TH + cell number, as reported previously. Moreover, we show for the first time that brain-derived neurotrophic factor (BDNF) exerts similar effects, with a large (110%) increase in NE uptake and a modest (20%) increase in TH + cell number. Cotreatment of LC cultures with morphine and NT-3 resulted in an attenuation of the NT-3 effect on both NE uptake and the number of TH + cells. In contrast, cotreatment of LC cultures with morphine and NT-4 or BDNF attenuated the neurotrophin effect on TH + cell number but not on NE uptake. Our results raise the possibility that opioid peptides may modulate the influence of neurotrophins on LC neuronal survival and differentiation.
KW - Cyclic AMP
KW - Development
KW - Norepinephrine uptake
KW - Opioid
KW - Tyrosine hydroxylase
UR - http://www.scopus.com/inward/record.url?scp=0028865336&partnerID=8YFLogxK
U2 - 10.1016/0006-8993(95)01029-8
DO - 10.1016/0006-8993(95)01029-8
M3 - Article
C2 - 8846066
AN - SCOPUS:0028865336
SN - 0006-8993
VL - 702
SP - 117
EP - 125
JO - Brain Research
JF - Brain Research
IS - 1-2
ER -