In vivo microdialysis of corticotropin releasing factor (CRF): calcium dependence of depolarization-induced neurosecretion of CRF.
Corticotropin releasing factor (CRF) is a large neuropeptide which functions as a major neurotransmitter in physiological stress responses. We have developed a microdialysis method for detecting CRF release from the median eminence of anesthetized rats. Depolarizing concentrations of KCl increased release of CRF into the perfusion media; this effect was inhibited by 100 microM verapamil. Our characterization of the physiologic conditions of KCl-induced release of neuronal CRF using the microdialysis technique provides evidence that the CRF release system is Ca(2+)-dependent and maintains its integrity over many hours in anesthetized rats.
Gabr
R W
RW
Department of Neurology, West Virginia University, Robert C. Byrd Health Sciences Center, Morgantown 26506.
Gladfelter
W E
WE
Birkle
D L
DL
Azzaro
A J
AJ
D000818:Animals; D002118:Calcium / Q000502:physiology*; D003346:Corticotropin-Releasing Hormone / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008473:Median Eminence / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D017551:Microdialysis; D009467:Neuromuscular Depolarizing Agents / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009489:Neurosecretion / Q000502:physiology*; D011189:Potassium Chloride / Q000037:antagonists & inhibitors / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D014700:Verapamil / Q000494:pharmacology
D009467:Neuromuscular Depolarizing Agents; D011189:Potassium Chloride; D003346:Corticotropin-Releasing Hormone; D014700:Verapamil; D002118:Calcium