Why the study?
Does phenylephrine reduce stress-induced orthostatic hypotension in a rat model of autonomic imbalance?
Does phenylephrine reduce stress-induced orthostatic hypotension in a rat model of autonomic imbalance?
Phenylephrine reduces orthostatic hypotension in a rat model of autonomic imbalance, suggesting that sympathetic dysfunction is a key underlying factor.
BACKGROUND: Specific alternation of rhythm in temperature (SART)-stressed rats, an animal model of autonomic imbalance, exhibit low blood pressure and tachycardia during consciousness and under anesthesia. In addition, these rats easily develop orthostatic hypotension (OH) as a response to postural manipulation. Hence, we studied the influence of the adrenalin α1-receptor agonist phenylephrine on stress-induced OH in SART-stressed rats and unstressed rats. METHODS: Male Wistar rats weighing 250-300 g were used. Rats were fixed in the supine position under urethane anesthesia. Blood pressure was directly measured from the left common carotid artery and ECG was recorded simultaneously. RESULTS: The maximum decrease in blood pressure and the area under the blood pressure-time curve were both large, while the %reflex was small in the SART-stressed rats compared with unstressed rats. In the SART-stressed rats, prolonged intravenous administration of phenylephrine reduced OH at a dose that barely affected unstressed rats. CONCLUSION: The results suggested that sympathetic dysfunction is a factor underlying SART stress-induced OH.
No takes yet. Share an insight, caveat, or question.
Funakami et al. (2010) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: