Journal article
Haemodynamic responses to conflict stress in borderline hypertensive rats
Journal of hypertension, Vol.7(7), pp.585-593
07/1989
DOI: 10.1097/00004872-198907000-00010
PMID: 2760459
Abstract
Chronic exposure to a shock-shock conflict paradigm (2 h/day, 5 days/week for 12 weeks [1]) produces hypertension in the borderline hypertensive rat (BHR), a cross between the spontaneously hypertensive rat (SHR) and the Wistar-Kyoto rat (WKY). The purpose of the present study was to characterize the regional haemodynamic responses which take place during conflict-stress.A pulsed Doppler flowmeter and miniature probes implanted on the left renal and superior mesenteric arteries and the abdominal aorta were used to record changes in regional flow velocity. Recording of mean arterial pressure (MAP) allowed changes in regional resistance to be calculated.The first conflict session produced intense splanchnic and renal vasoconstriction and hindquarter vasodilation. Pressor responses were moderate. A second group of BHRs was studied during conflict sessions 17-18, prior to the development of hypertension. This group exhibited faster habituation to the stress than the group studied during the first conflict sessionMAP and mesenteric resistance returned more rapidly towards pre-stress levels. Relative to naive control rats, this group exhibited a larger peak MAP and less tachycardia in response to a neutral stressor (air-jet stress) and a smaller reduction in renal resistance in response to ganglionic blockade.These data suggest that in this model, pressure load per se is moderate. More attention should be directed towards the role of trophic effects of the neurohumoral factors responsible for the pronounced constriction of splanchnic and renal vasculature in producing hypertension.
Details
- Title: Subtitle
- Haemodynamic responses to conflict stress in borderline hypertensive rats
- Creators
- Stein Knardahl - From the Departments of Psychology and Pharmacology, and the Cardiovascular Center, University of Iowa, Iowa City, IA 52242, USA Present address: Department of Environmental Toxicology, Norwe gian Defence Research Establishment, PO Box 25, N-2007 Kjeller, NorwayBrian SandersAlan Johnson
- Resource Type
- Journal article
- Publication Details
- Journal of hypertension, Vol.7(7), pp.585-593
- Publisher
- Lippincott-Raven Publishers
- DOI
- 10.1097/00004872-198907000-00010
- PMID
- 2760459
- ISSN
- 0263-6352
- eISSN
- 1473-5598
- Language
- English
- Date published
- 07/1989
- Academic Unit
- Psychological and Brain Sciences; Neuroscience and Pharmacology; Health and Human Physiology
- Record Identifier
- 9984213415402771
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