Abstract
The exercise pressor reflex is opposed by the arterial baroreflex, and circulating peptides may act in the area postrema to enhance this inhibition. Therefore, we tested the hypothesis that the area postrema exerts an inhibitory effect on this reflex. Consequently, in six α-chloralose- anesthetized cats, blood pressure and heart rate responses to 30 s of electrically stimulated hindlimb contraction were compared before and after thermal coagulation of the area postrema. In six other cats, the same contraction induced cardiovascular responses were assessed before and after chemical lesion of the area postrema using kainic acid (214 ± 9 nl, 2.5-5 mM). Thermal lesion of the area postrema augmented blood pressure and heart rate responses to contraction from 29 ± 5 to 47 ± 7 mmHg (P < 0.05) and from 8 ± 2 to 14 ± 2 beats/min (P < 0.05), respectively. Chemical lesion of the area postrema enhanced contraction-evoked blood pressure (30 ± 7 vs. 47 ± 6 mmHg, P < 0.05) and heart rate (12 ± 4 vs. 17 ± 4 beats/min, P < 0.05) responses. These data suggest that the area postrema attenuates the exercise presser reflex, possibly through the actions of circulating peptides on baroreflex function.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Heart and Circulatory Physiology |
| Volume | 272 |
| Issue number | 4 41-4 |
| State | Published - 1997 |
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Keywords
- arginine vasopressin
- kainic acid
ASJC Scopus subject areas
- Physiology
Cite this
Area postrema-induced inhibition of the exercise presser reflex. / Bonigut, Stefanie; Bonham, Ann C.; Stebbins, Charles L.
In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 272, No. 4 41-4, 1997.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Area postrema-induced inhibition of the exercise presser reflex
AU - Bonigut, Stefanie
AU - Bonham, Ann C.
AU - Stebbins, Charles L
PY - 1997
Y1 - 1997
N2 - The exercise pressor reflex is opposed by the arterial baroreflex, and circulating peptides may act in the area postrema to enhance this inhibition. Therefore, we tested the hypothesis that the area postrema exerts an inhibitory effect on this reflex. Consequently, in six α-chloralose- anesthetized cats, blood pressure and heart rate responses to 30 s of electrically stimulated hindlimb contraction were compared before and after thermal coagulation of the area postrema. In six other cats, the same contraction induced cardiovascular responses were assessed before and after chemical lesion of the area postrema using kainic acid (214 ± 9 nl, 2.5-5 mM). Thermal lesion of the area postrema augmented blood pressure and heart rate responses to contraction from 29 ± 5 to 47 ± 7 mmHg (P < 0.05) and from 8 ± 2 to 14 ± 2 beats/min (P < 0.05), respectively. Chemical lesion of the area postrema enhanced contraction-evoked blood pressure (30 ± 7 vs. 47 ± 6 mmHg, P < 0.05) and heart rate (12 ± 4 vs. 17 ± 4 beats/min, P < 0.05) responses. These data suggest that the area postrema attenuates the exercise presser reflex, possibly through the actions of circulating peptides on baroreflex function.
AB - The exercise pressor reflex is opposed by the arterial baroreflex, and circulating peptides may act in the area postrema to enhance this inhibition. Therefore, we tested the hypothesis that the area postrema exerts an inhibitory effect on this reflex. Consequently, in six α-chloralose- anesthetized cats, blood pressure and heart rate responses to 30 s of electrically stimulated hindlimb contraction were compared before and after thermal coagulation of the area postrema. In six other cats, the same contraction induced cardiovascular responses were assessed before and after chemical lesion of the area postrema using kainic acid (214 ± 9 nl, 2.5-5 mM). Thermal lesion of the area postrema augmented blood pressure and heart rate responses to contraction from 29 ± 5 to 47 ± 7 mmHg (P < 0.05) and from 8 ± 2 to 14 ± 2 beats/min (P < 0.05), respectively. Chemical lesion of the area postrema enhanced contraction-evoked blood pressure (30 ± 7 vs. 47 ± 6 mmHg, P < 0.05) and heart rate (12 ± 4 vs. 17 ± 4 beats/min, P < 0.05) responses. These data suggest that the area postrema attenuates the exercise presser reflex, possibly through the actions of circulating peptides on baroreflex function.
KW - arginine vasopressin
KW - kainic acid
UR - http://www.scopus.com/inward/record.url?scp=0030913504&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030913504&partnerID=8YFLogxK
M3 - Article
C2 - 9139947
AN - SCOPUS:0030913504
VL - 272
JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
SN - 1931-857X
IS - 4 41-4
ER -