ISSN:
1432-2013
Keywords:
Blood pressure
;
Ventrolateral medulla
;
Intraventricular NaCl infusion
;
Norepinephrine
;
Microdialysis method
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Norepinephrine (NE) release in the ventrolateral medulla (VLM) was serially measured in anesthetized male Wistar rats during the rise in the blood pressure (BP) produced by acute intraventricular (ICV) administration of hypertonic (1.5 M) NaCl. Catecholamine release was determined by a brain microdialysis method using high performance liquid chromatography and electrochemical detector. The release of NE in the VLM was significantly decreased after ICV 1.5 M NaCl. In another set of rats, the pressor response to acute ICV 1.5 M NaCl was attenuated by selective administration of NE to the VLM using the microdialysis method. Chronic and continuous ICV infusion of 1.5 M NaCl to conscious rats caused an increase in BP on day 10 which was associated with a decrease in NE release in the VLM; concomitant ICV infusion of NE or of a synthetic NE precursor,l-threo-3,4-dihydroxyphenylserine (l-DOPS) prevented the rise in BP as well as the reduction in NE release. These results suggest that a decrease in the NE release of the VLM may contribute to the change in BP induced by ICV infusion of hypertonic saline.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00582141