Postexertional hypotension: A brief review

DiCarlo, Stephen E.; Collins, Heidi L.; Howard, Mary G.; Chen, Chao‐Yin; Scislo, Tadeusz J.; Patil, Rahul

doi:10.1080/15438629409511998

Cited by 28 publications

(25 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Exercise may also be a countermeasure for AD by reducing sympathetic nerve activity because a single bout of mild-to-moderate dynamic exercise often lowers postexercise sympathetic nerve activity for at least 1 h in individuals and animals (10, 13). Therefore, this study was designed to test the hypothesis that a single bout of dynamic exercise attenuates the response to colon distension (mechanism to elicit AD) in T 5 spinal rats.To test this hypothesis, the response to graded colon distension (10,30, 50, and 80 mmHg, in random order with at least 5 min between inflations) was determined before and 20 min after a single bout of mild-to-moderate dynamic exercise. All surgical and experimental procedures were reviewed and approved by the Institutional Animal Care and Use Committee and con-…”

mentioning

confidence: 99%

“…These data suggest that the ability to increase peripheral vascular resistance after exercise is significantly reduced. Exercise may also be a countermeasure for AD by reducing sympathetic nerve activity because a single bout of mild-to-moderate dynamic exercise often lowers postexercise sympathetic nerve activity for at least 1 h in individuals and animals (10,13). Therefore, this study was designed to test the hypothesis that a single bout of dynamic exercise attenuates the response to colon distension (mechanism to elicit AD) in T 5 spinal rats.…”

mentioning

confidence: 99%

“…To test this hypothesis, the response to graded colon distension (10,30,50, and 80 mmHg, in random order with at least 5 min between inflations) was determined before and 20 min after a single bout of mild-to-moderate dynamic exercise. All surgical and experimental procedures were reviewed and approved by the Institutional Animal Care and Use Committee and con-formed to the American Physiological Society "Guiding Principles in the Care and Use of Animals."…”

mentioning

confidence: 99%

“…In two rats, radiotelemetry devices (model TA11PA-C40; Data Sciences) were implanted in the abdominal cavities with the attached catheter inserted through the femoral artery and advanced into the descending aorta. After recovery (7 days) (20), the response to graded colon distension (10,30,50, and 80 mmHg, in random order with at least 5 min between inflations) was determined before and 20 min after a single bout of mild-to-moderate dynamic exercise. Two recent studies investigating mechanisms mediating AD examined the spinal rats 30 days posttransection (19,21).…”

mentioning

confidence: 99%

“…Although the mechanisms mediating this effect were not investigated, postexercise ␣-adrenergic receptor hyporesponsiveness (13,15,16,29,33) and sympathoinhibition may be the primary factors (10,14).…”

mentioning

confidence: 99%

See 4 more Smart Citations

Acute exercise reduces the response to colon distension in T₅ spinal rats

Collins

DiCarlo

2002

American Journal of Physiology-Heart and Circulatory Physiology

Self Cite

View full text Add to dashboard Cite

.-Individuals with spinal cord injuries above thoracic level 6 (T 6) experience life-threatening bouts of hypertension, termed autonomic dysreflexia (AD). AD is mediated by peripheral ␣-adrenergic receptor supersensitivity as well as a reorganization of spinal pathways controlling sympathetic preganglionic neurons. A single bout of dynamic exercise may be a safe therapeutic approach to reduce the severity of AD because mild-to-moderate dynamic exercise reduces postexercise ␣-adrenergic receptor responsiveness, lowers postexercise sympathetic nerve activity, and reduces the postexercise response to stress. Therefore, this study was designed to test the hypothesis that mild-to-moderate dynamic exercise attenuates the postexercise response to colon distension (mechanism to elicit AD). To test this hypothesis, six male Wistar rats (406 Ϯ 23 g), 5 wk post-T 5 spinal cord transection, were instrumented with an arterial catheter. After recovery, the response to graded colon distension (10, 30, 50, and 80 mmHg, in random order) was determined before and after a single bout of mild-to-moderate dynamic exercise (9-12 m/min, 0% grade for 40 min). After exercise, the pressor response to graded colon distension was significantly attenuated (preexercise change: 2 Ϯ 1, 9 Ϯ 1, 14 Ϯ 1, and 24 Ϯ 2 vs. postexercise change: 2 Ϯ 1, 2 Ϯ 1, 9 Ϯ 1, and 12 Ϯ 3 mmHg). Thus acute exercise is a safe, therapeutic approach to reduce the severity of AD in paraplegic subjects. autonomic dysreflexia; spinal cord injury AUTONOMIC REGULATION of the cardiovascular system is abnormal and unstable after spinal cord injury. Hypotension occurs immediately after the injury because of loss of tonic supraspinal excitatory drive to spinal sympathetic neurons (3). Subsequently, resting arterial pressure returns toward normal values; however, episodic bouts of hypertension often develop as part of the condition termed autonomic dysreflexia (AD) (24,27). AD occurs in as many as 85% of individuals with lesions above thoracic level 6 (T 6 ) and is characterized by severe hypertension. The paroxysmal hypertension can be caused by stimulation of the skin, distension of the urinary bladder or colon, and muscle spasms (4, 23). If not treated promptly, the hypertension may produce cerebral and subarachnoid hemorrhage, seizures, and renal failure and may lead to death (25). The long-term consequence of repeated episodes of severe hypertension has yet to be determined.Exercise may be a safe therapeutic approach for attenuating the severity of AD by reducing ␣-adrenergic receptor responsiveness. Several investigators have demonstrated that a single bout of mild-to-moderate dynamic exercise significantly attenuated the postexercise response to ␣-adrenergic receptor agonists (14-16, 29, 33). For example, a single bout of dynamic exercise significantly attenuated the postexercise response to ␣-adrenergic receptor activation in the intact conscious rabbit (15), rat (29, 33), and human (14). These data suggest that the ability to increase peripheral vascular resistance aft...

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%