Thyrotropin-releasing hormone-immunoreactive projections to the dorsal motor nucleus and the nucleus of the solitary tract of the rat

1991 ◽  
Vol 311 (2) ◽  
pp. 271-288 ◽  
Author(s):  
Richard B. Lynn ◽  
Margaret S. Kreider ◽  
Richard R. Miselis
2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Jianhua Liu ◽  
Wenbin Fu ◽  
Wei Yi ◽  
Zhenhua Xu ◽  
Nenggui Xu

Acupuncture has a reflex regulation in gastrointestinal functions, which is characterized with segment. In the present study, the neural pathway of electroacupuncture (EA) at orofacial acupoints (ST2) on gastric myoelectric activity (GMA) in rats was investigated. The results indicated that EA at ST2 facilitated spike bursts of GMA, which is similar to EA at limbs and opposite to EA at abdomen. The excitatory effect was abolished by the transaction of infraorbital nerves, dorsal vagal complex lesion, and vagotomy, respectively. In addition, microinjection of L-glutamate into the nucleus of the solitary tract (NTS) attenuated the excitatory effect. All these data suggest that the dorsal vagal complex is involved in the reflex regulation of EA at orofacial acupoints on gastric functions and NTS-dorsal motor nucleus of the vagus (DMV) inhibitory connections may be essential for it.


2004 ◽  
Vol 91 (5) ◽  
pp. 2330-2343 ◽  
Author(s):  
Zhenjun Tan ◽  
Ronald Fogel ◽  
Chunhui Jiang ◽  
Xueguo Zhang

Galanin plays an important role in the regulation of food intake, energy balance, and body weight. Many galanin-positive fibers as well as galanin-positive neurons were seen in the dorsal vagal complex, suggesting that galanin produces its effects by actions involving vagal neurons. In the present experiment, we used tract-tracing and neurophysiological techniques to evaluate the origin of the galaninergic fibers and the effect of galanin on neurons in the dorsal vagal complex. Our results reveal that the nucleus of the solitary tract is the major source of the galanin terminals in the dorsal vagal complex. In vivo experiments demonstrated that galanin inhibited the majority of gut-related neurons in the dorsal motor nucleus of the vagus. In vitro experiments demonstrated that galanin inhibited the majority of stomach-projecting neurons in the dorsal motor nucleus of the vagus by suppressing spontaneous activity and/or producing a fully reversible dose-dependent membrane hyperpolarization and outward current. The galanin-induced hyperpolarization and outward current persisted after synaptic input was blocked, suggesting that galanin acts directly on receptors of neurons in the dorsal motor nucleus of the vagus. The reversal potential induced by galanin was close to the potassium ion potentials of the Nernst equation and was prevented by the potassium channel blocker tetraethylammonium, indicating that the inhibitory effect of galanin was mediated by a potassium channel. These results indicate that the dorsal motor nucleus of the vagus is inhibited by galanin derived predominantly from neurons in the nucleus of the solitary tract projecting to the dorsal motor nucleus of the vagus nerve. Galanin is one of the neurotransmitters involved in the vago-vagal reflex.


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