Dopaminergic modulation on respiratory rhythm in rat brainstem-spinal cord preparation.
Dopamine (DA) is known to regulate both higher order and autonomic brain functions. To elucidate the effects of DA on respiratory rhythm generation, isolated brainstem-spinal cord was treated with DA and each DA receptor agonist individually. DA application facilitated respiratory rhythm in pons-medulla-spinal cord preparations, but depressed it in medulla-spinal cord preparations. Furthermore, we found that DA application depressed Pre-Inspiratory (Pre-I) neurons but not Inspiratory or Expiratory neurons and that among the various DA receptor agonists, only a D4 agonist, PD168077, depressed respiratory rhythm. Therefore, the primary target of DA action in modulating respiratory rhythm generation is the Pre-I neurons in the medulla.
Laboratory for Memory and Learning, Brain Science Institute, RIKEN 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
Morimitsu
M
Fujii
Kazuo
K
Umezawa
Akiko
A
Arata
D000818:Animals; D001933:Brain Stem / Q000187:drug effects* / Q000502:physiology; D003655:Decerebrate State / Q000503:physiopathology; D004298:Dopamine / Q000494:pharmacology* / Q000502:physiology; D018491:Dopamine Agonists / Q000494:pharmacology; D066298:In Vitro Techniques; D051381:Rats; D017208:Rats, Wistar; D015656:Respiratory Mechanics / Q000187:drug effects* / Q000502:physiology; D013116:Spinal Cord / Q000187:drug effects* / Q000502:physiology
D018491:Dopamine Agonists; D004298:Dopamine