scholarly journals Increased Mesohippocampal Dopaminergic Activity and Improved Depression-Like Behaviors in Maternally Separated Rats Following Repeated Fasting/Refeeding Cycles

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Jeong Won Jahng ◽  
Sang Bae Yoo ◽  
Jin Young Kim ◽  
Bom-Taeck Kim ◽  
Jong-Ho Lee
Keyword(s):  
Dopaminergic Neurons ◽  
Eating Behaviors ◽  
Maternal Separation ◽  
Brain Dopamine ◽  
Ambulatory Activity ◽  
Dopaminergic Activity ◽  
Midbrain Dopaminergic Neurons ◽  
Underlying Mechanisms ◽  
Increased Activity ◽  
Pituitary Adrenal Axis

We have previously reported that rats that experienced 3 h of daily maternal separation during the first 2 weeks of birth (MS) showed binge-like eating behaviors with increased activity of the hypothalamic-pituitary-adrenal axis when they were subjected to fasting/refeeding cycles repeatedly. In this study, we have examined the psychoemotional behaviors of MS rats on the fasting/refeeding cycles, together with their brain dopamine levels. Fasting/refeeding cycles normalized the ambulatory activity of MS rats, which was decreased by MS experience. Depression-like behaviors, but not anxiety, by MS experience were improved after fasting/refeeding cycles. Fasting/refeeding cycles did not significantly affect the behavioral scores of nonhandled (NH) control rats. Fasting/refeeding cycles increased dopamine levels not only in the hippocampus but also in the midbrain dopaminergic neurons in MS rats, but not in NH controls. Results demonstrate that fasting/refeeding cycles increase the mesohippocampal dopaminergic activity and improve depression-like behaviors in rats that experienced MS. Together with our previous paper, it is suggested that increased dopamine neurotransmission in the hippocampus may be implicated in the underlying mechanisms by which the fasting/refeeding cycles induce binge-like eating and improve depression-like behaviors in MS rats.

A pair of dopamine neurons mediate chronic stress signals to induce learning deficit in Drosophila melanogaster

2021 ◽  
Vol 118 (42) ◽  
pp. e2023674118
Author(s):  
Jia Jia ◽  
Lei He ◽  
Junfei Yang ◽  
Yichun Shuai ◽  
Jingjing Yang ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Chronic Stress ◽  
Dopaminergic Neurons ◽  
Mushroom Body ◽  
Dopamine Neurons ◽  
Learning Deficit ◽  
Dopaminergic Activity ◽  
Output Neurons ◽  
Stress Signals ◽  
Underlying Mechanisms

Chronic stress could induce severe cognitive impairments. Despite extensive investigations in mammalian models, the underlying mechanisms remain obscure. Here, we show that chronic stress could induce dramatic learning and memory deficits in Drosophila melanogaster. The chronic stress–induced learning deficit (CSLD) is long lasting and associated with other depression-like behaviors. We demonstrated that excessive dopaminergic activity provokes susceptibility to CSLD. Remarkably, a pair of PPL1-γ1pedc dopaminergic neurons that project to the mushroom body (MB) γ1pedc compartment play a key role in regulating susceptibility to CSLD so that stress-induced PPL1-γ1pedc hyperactivity facilitates the development of CSLD. Consistently, the mushroom body output neurons (MBON) of the γ1pedc compartment, MBON-γ1pedc>α/β neurons, are important for modulating susceptibility to CSLD. Imaging studies showed that dopaminergic activity is necessary to provoke the development of chronic stress–induced maladaptations in the MB network. Together, our data support that PPL1-γ1pedc mediates chronic stress signals to drive allostatic maladaptations in the MB network that lead to CSLD.

scholarly journals Neurotensin Induces Presynaptic Depression of D2 Dopamine Autoreceptor-Mediated Neurotransmission in Midbrain Dopaminergic Neurons

2015 ◽  
Vol 35 (31) ◽  
pp. 11144-11152 ◽  
Author(s):  
E. Piccart ◽  
N. A. Courtney ◽  
S. Y. Branch ◽  
C. P. Ford ◽  
M. J. Beckstead
Keyword(s):  
Dopaminergic Neurons ◽  
Dopamine Autoreceptor ◽  
Midbrain Dopaminergic Neurons

Midbrain dopaminergic innervation of the hippocampus is sufficient to modulate formation of aversive memories

2021 ◽  
Vol 118 (40) ◽  
pp. e2111069118
Author(s):  
Theodoros Tsetsenis ◽  
Julia K. Badyna ◽  
Julianne A. Wilson ◽  
Xiaowen Zhang ◽  
Elizabeth N. Krizman ◽  
...  
Keyword(s):  
Dopaminergic Neurons ◽  
Dorsal Hippocampus ◽  
Memory Formation ◽  
Dopamine Neurons ◽  
Substantia Nigra Pars Compacta ◽  
Aversive Learning ◽  
Contextual Fear ◽  
Dopaminergic Transmission ◽  
Midbrain Dopaminergic Neurons ◽  
Midbrain Dopamine

Aversive memories are important for survival, and dopaminergic signaling in the hippocampus has been implicated in aversive learning. However, the source and mode of action of hippocampal dopamine remain controversial. Here, we utilize anterograde and retrograde viral tracing methods to label midbrain dopaminergic projections to the dorsal hippocampus. We identify a population of midbrain dopaminergic neurons near the border of the substantia nigra pars compacta and the lateral ventral tegmental area that sends direct projections to the dorsal hippocampus. Using optogenetic manipulations and mutant mice to control dopamine transmission in the hippocampus, we show that midbrain dopamine potently modulates aversive memory formation during encoding of contextual fear. Moreover, we demonstrate that dopaminergic transmission in the dorsal CA1 is required for the acquisition of contextual fear memories, and that this acquisition is sustained in the absence of catecholamine release from noradrenergic terminals. Our findings identify a cluster of midbrain dopamine neurons that innervate the hippocampus and show that the midbrain dopamine neuromodulation in the dorsal hippocampus is sufficient to maintain aversive memory formation.

scholarly journals Neurturin Exerts Potent Actions on Survival and Function of Midbrain Dopaminergic Neurons

1998 ◽  
Vol 18 (13) ◽  
pp. 4929-4937 ◽  
Author(s):  
Brian A. Horger ◽  
Merry C. Nishimura ◽  
Mark P. Armanini ◽  
Li-Chong Wang ◽  
Kris T. Poulsen ◽  
...  
Keyword(s):  
Dopaminergic Neurons ◽  
Midbrain Dopaminergic Neurons ◽  
And Function
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