Neuro Pathways in cardiovascular electroacupuncture response

Technical article looking at low frequency electroacupuncture in cats at P5 and P6 and the brain circuits responsible for the cardiac sympathoinhibition. Cardiac sympathoinhibition is another way to say a decrease in the stress response. The last blog post was looking at overall increased sympathetic tone in PCOS patients. This particular treatment at P5 and P6 might help to further decrease sympathetic tone in addition to the protocol described by Stener-Vitorin.
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Nucleus raphe pallidus participates in midbrain-medullary cardiovascular sympathoinhibition during electroacupuncture.
Am J Physiol Regul Integr Comp Physiol. 2010 Nov;299(5):R1369-76. Epub 2010 Aug 18.
Li P, Tjen-A-Looi SC, Longhurst JC.

Susan Samueli Center for Integrative Medicine, Department of Medicine, School of Medicine, University of California, Irvine, Irvine, California 92697-4075, USA. pengli@uci.edu
Abstract:
We have shown that electroacupuncture (EA) inhibits sympathoexcitatory rostral ventrolateral medulla (rVLM) neurons and reflex responses following activation of a long-loop pathway in the arcuate nucleus and ventrolateral periaqueductal gray (vlPAG). Additionally, EA at P 5-6 acupoints (overlying the median nerve) activates serotonin-containing neurons in the nucleus raphé pallidus (NRP), which, in turn, inhibit rVLM neurons. Although direct projections from the vlPAG to the rVLM exist, it is uncertain whether an indirect pathway through the NRP serves an important role in vlPAG-rVLM cardiovascular modulation. Therefore, the splanchnic nerve (SN) was stimulated to induce cardiovascular sympathoexcitatory reflexes, and EA was applied at P 5-6 acupoints in a-chloralose-anesthetized cats. A single-barreled recording electrode was inserted into the NRP or rVLM. Microinjection of DL-homocysteic acid (DLH) into the vlPAG increased the NRP neuronal response to SN stimulation (5 ± 1 to 12 ± 2 spikes/30 stim). Likewise, EA at P 5-6 for 30 min increased the NRP response to SN stimulation (3 ± 1 to 10 ± 2 spikes/30 stim), an effect that could be blocked by microinjection of kynurenic acid (KYN) into the caudal vlPAG. Furthermore, the reflex increase in blood pressure induced by application of bradykinin to the gallbladder and the rVLM cardiovascular presympathetic neuronal response to SN stimulation was inhibited by injection of DLH into the vlPAG, a response that was reversed by injection of KYN into the NRP. These results indicate that EA activates the vlPAG, which excites the NRP to, in turn, inhibit rVLM presympathetic neurons and reflex cardiovascular sympathoexcitatory responses.

Is polycystic ovary syndrome associated with high sympathetic nerve activity and size at birth?

This article is back up information about PCOS and high sympathetic tone. They were measuring sympathetic nerve activity to the muscle vascular bed (MSNA.) They found that the heightened MSNA may account for the higher cardiovascular risk in PCOS patients, and postulate that the higher sympathetic tone may account for many of the abnormalities encountered in PCOS. They cite one previous study that explored HRV and PCOS, which I will try to track down. I'm excerpting almost in its entirety for those who might be as interested as I am in this topic.
(For more information about my practice, please click here.)

Yrsa Bergmann Sverrisdo´ttir,1 Tove Mogren,1 Josefin Kataoka,1 Per Olof Janson,2
and Elisabet Stener-Victorin Institute of Neuroscience and Physiology, Department of Physiology, and 2Department of Obstetrics and Gynecology,Sahlgrenska Academy, Go¨teborg University, Go¨teborg, Sweden
Am J Physiol Endocrinol Metab 294: E576–E581, 2008.

Is polycystic ovary syndrome associated with high sympathetic
nerve activity and size at birth?
Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disturbance among women ofreproductive age and is proposed to be linked with size at birth and
increased prevalence of cardiovascular disease. A disturbance in the
sympathetic nervous system may contribute to the etiology of PCOS.
This study evaluates sympathetic outflow in PCOS and its relation to
size at birth. Directly recorded sympathetic nerve activity to the
muscle vascular bed (MSNA) was obtained in 20 women with PCOS
and in 18 matched controls. Ovarian ultrasonographic evaluation,
biometric, hormonal, and biochemical parameters were measured, and
birth data were collected. Women with PCOS had increased MSNA compared with
controls. MSNA was positively related to testosterone and cholesterol levels in PCOS, which, in turn, were not related to each other. Testosterone level was a stronger predictor of MSNA than cholesterol. Birth size did not differ between the study groups. This is the first study to directly address sympathetic nerve activity in women with PCOS and shows that PCOS is associated with high MSNA. Testosterone and cholesterol levels are identified as independent predictors of MSNA in PCOS, although testosterone has a stronger impact. The increased MSNA in PCOS may contribute to the increased cardiovascular risk and etiology of the condition. In this study, PCOS was not related to size at birth.