Involvement of Neuropeptide Y within Paraventricular Nucleus in Electroacupuncture Inhibiting Sympathetic Activities...

Area of Science:

• Neuroscience
• Cardiovascular Physiology
• Integrative and Complementary Medicine

Background:

• Electroacupuncture (EA) is clinically used to reduce blood pressure (BP), but its mechanisms remain unclear.
• Hypertension involves dysregulated sympathetic activity and neuropeptide Y (NPY) signaling.
• The paraventricular nucleus (PVN) plays a crucial role in cardiovascular regulation.

Purpose of the Study:

• To investigate if EA lowers BP by suppressing sympathetic activity and modulating NPY function in the PVN.
• To elucidate the neurobiological mechanisms underlying EA's antihypertensive effects in a rat model.

Main Methods:

• Hypertension was induced in rats using the two-kidney, one-clip (2K1C) method.
• EA was applied daily for 30 days to specific acupoints.
• Cardiovascular parameters, sympathetic activity markers (norepinephrine, epinephrine), and NPY expression in the PVN were assessed.

Main Results:

• EA treatment significantly reduced elevated BP and sympathetic activity in 2K1C rats.
• EA upregulated NPY mRNA and protein expression in the PVN.
• EA enhanced the pressor response to NPY Y1 receptor antagonist microinjection, indicating increased endogenous NPY tone.

Conclusions:

• EA exerts antihypertensive effects by suppressing sympathetic activity and enhancing NPYergic neurotransmission in the PVN.
• Increased NPY expression and function in the PVN contribute to EA's hypotensive action.
• These findings support acupuncture as a potential therapeutic strategy for hypertension.