Related Experiment Videos
Prefrontal stimulus-produced hypotension in rat
1Department of Anatomy, University of Mississippi Medical Center, Jackson 39216.
Experimental Brain Research
|January 1, 1988
Summary
Electrical stimulation of rat frontal cortex can cause hypotension and bradycardia. This stimulus-produced hypotension is not vagus nerve-mediated but may involve sympathetic inhibition and opioid pathways.
Area of Science:
- Neuroscience
- Cardiovascular Physiology
Background:
- The frontal cortex plays a role in regulating autonomic functions.
- Understanding the neural pathways involved in cardiovascular control is crucial.
Purpose of the Study:
- To investigate the effects of electrical stimulation of different frontal cortex regions on blood pressure and heart rate in rats.
- To elucidate the neural mechanisms underlying stimulus-produced hypotension (SPH).
Main Methods:
- Bipolar electrical stimulation of medial prefrontal cortex (MPFC), lateral prefrontal cortex (LPFC), infralimbic cortex, and convexity cortex in rats.
- Monitoring of blood pressure and heart rate.
- Pharmacological and surgical blockade of vagus nerves.
- Administration of norepinephrine and naloxone.
Main Results:
- Stimulation of LPFC, infralimbic cortex, and ventral MPFC induced hypotension.
- LPFC stimulation caused bradycardia; MPFC and infralimbic cortex stimulation had minimal heart rate effects.
- Vagus nerve blocks did not alter SPH.
- Norepinephrine and naloxone administration completely blocked SPH.
Conclusions:
- Stimulus-produced hypotension in rats is not mediated by vagus nerves.
- SPH may result from sympathetic inhibition.
- Opioid pathways may play a role in mediating SPH.