Objective

2

To observe the effects of acupuncture at "antihypertensive acupoint prescription" on endothelial active factors and related autonomic neurotransmitters in spontaneous hypertension rats

and explore the vascular regulation and central regulation mechanisms of acupuncture for anti-hypertension.

Methods

2

Thirty SPF grade male spontaneous hypertension rats were randomly divided into a model group (15 rats) and an acupuncture group (15 rats).Besides

15 Wistar Kyoto rats were collected as a blank control group (normal group).In the acupuncture group

acupuncture was delivered at the "antihypertensive acupoint prescription" (bilateral "Renying" [ST 9]

"Quchi" [LI 11]

"Zusanli" [ST 36]

"Taichong" [LR 3] and "Neiguan" [PC 6])

with needles retained for 30 min

once daily.The duration of intervention was 28 days.Every week

using the the irritation scale

the sign of sympathetic irritation was evaluated dynamically.The arterial blood pressure of the rats tail was determined

using non-invasive blood pressure measurement system.ELISA was adopted to detect the levels of calcitonin gene-related peptide (CGRP)

nitric oxide (NO)

endothelin-1 (ET-1)

neuropeptide Y (NPY) in the serum.DAB chromogenic in situ hybridization (CISH) was provided to detect the mRNA expression of endothelial nitric oxide synthase (eNOS) in the internal carotid artery and the arcuate nucleus (ARC)

and that of CGRP in the paraventricular nucleus posterior (PVP) and the ventrolateral medulla (VLM).Liquid chromatography-mass spectrometry (LC-MS) was used to detect the levels of epinephrine (E) and norepinephrine (NE) in the paraventricular nucleus anterior (PVA).

Results

2

Compared with the normal group

the irritation scores

systolic blood pressure and diastolic blood pressure were increased at each time point in the model group (

P

<

0.05).When compared with the model group

the irritation scores after the intervention for 3 and 4 weeks

and systolic and diastolic blood pressure after intervention for 2

3 and 4 weeks were reduced in the acupuncture group (

P

<

0.05).In comparison with the normal group

the serum CGRP and NO levels of the rats were decreased (

P

<

0.05)

and the serum ET-1 and NPY levels

as well as E and EN levels in PVA were increased (

P

<

0.05) in the model group.The levels of serum CGRP and NO were elevated (

P

<

0.05)

and the serum ET-1 and NPY levels

as well as E and EN levels of PVA were reduced (

P

<

0.05) in the acupuncture group when compared with those of the model group.In the model group

the media of internal carotid artery exhibited thickening and remodeling

while the neuron volume in ARC was small.In the acupuncture group

every layer of internal carotid artery was acceptably arranged

and the parvicellular neuron of ARC was moderate in volume.For the in situ hybridization of eNOS mRNA for the rats of each group

the smooth muscle cells were predominantly expressed in each layer of the internal carotid artery

whereas the expression of parvicellular neurons was dominated in ARC.In the model group

the large and small neurosecretory cells were distributed sparsely in the nerves of PVP; in the acupuncture group

the cells of these two species were

distributed regularly; and there were few species of glial cell in the VLM of either the model group or the acupuncture group.In each group

for the in situ hybridization of CGRP mRNA

the small neurosecretory cells were expressed predominately in the PVP

while

the expression of glial cell nuclei and the cell cytoplasm was dominated in the VLM.Compared with the normal group

the mRNA expression of eNOS in the internal carotid artery and ARC and that of CGRP mRNA in the PVP and VLM was decreased in the model group (

P

<

0.05).In the acupuncture group

when compared with the model group

the mRNA expression of eNOS in the internal carotid artery and ARC and that of CGRP in the PVP and VLM was increased in the acupuncture group (

P

<

0.05).

Conclusion

2

Acupuncture at "antihypertensive acupoint prescription" can upregulate the level of vascular relaxing factors

downregulate the level of contracting factors

enhance the response of relaxing factors in targeting blood vessels and regulating the center.The mechanism may be related to the modulation of the sympathetic-adrenergic autonomic neurotransmitters in the paraventricular nucleus in spontaneous hypertension rats.