Sympathetic hyperactivity during hypothalamic stimulation in spontaneously hypertensive rats.
The Journal of Clinical Investigation
|September 1, 1978
Summary
Sympathetic hyperactivity originating in the posterior hypothalamus contributes to elevated blood pressure in spontaneous hypertension. This hyperactivity is characterized by increased sympathetic nerve firing during hypothalamic stimulation in hypertensive rats.
Area of Science:
- Neuroscience
- Cardiovascular Physiology
- Hypertension Research
Background:
- Spontaneous hypertension involves elevated blood pressure.
- The role of the posterior hypothalamus in maintaining hypertension is not fully understood.
Purpose of the Study:
- To investigate if sympathetic hyperactivity from the posterior hypothalamus contributes to sustained high blood pressure in spontaneous hypertension.
Main Methods:
- Recorded aortic pressure and sympathetic nerve activity in anesthetized normotensive and hypertensive rats.
- Stimulated the posterior hypothalamus electrically.
Main Results:
- Spontaneously hypertensive rats exhibited higher basal sympathetic nerve activity.
- Hypothalamic stimulation increased blood pressure and sympathetic nerve firing rates more significantly in spontaneous hypertensives.
- Recovery from post-stimulation nerve inhibition was faster in spontaneous hypertensives.
Conclusions:
- Sympathetic hyperactivity from the posterior hypothalamus plays a role in spontaneous hypertension.
- Enhanced responsiveness to hypothalamic stimulation suggests mechanisms beyond general cardiovascular reactivity.
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