Carotid Baroreceptor Influences on Peripheral Circulatory and Thermal Responses during Cold Exposure,
Abstract
The effects of varying the pressure within a vascularly isolated carotid sinus on peripheral circulatory and thermal responses during hindlimb exposure to room air and cold were determined in anesthetized cats. A sigmoidal relationship between heart rate and carotid pressure was observed only during exposure to room air, suggesting that cold-induced somatosympathetic reflexes may override the carotid baroreflex effects on heart rate. At low carotid pressures, mean arterial pressure increased, femoral arterial vascular resistance decreased, femoral arterial blood flow increased, footpad thermal insulation decreased, footpad temperature increased, and footpad heat loss increased. Opposite responses were observed at high carotid pressures. These trends were observed during hindlimb exposure to both room air and cold. The persistence of baroreceptor effects on peripheral circulatory and thermal responses in a locally cold-exposed hindlimb provides evidence that cold-induced vasodilatory responses may be mediated by baroreceptor reflexes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1984
- Accession Number
- ADA146808
Entities
People
- C. A. Ohata
- G. D. Powers
- P. H. Scaglione
Organizations
- United States Army Research Institute of Environmental Medicine