A Calibrated Method of Massage Therapy Decreases Systolic Blood Pressure Concomitant With Changes in Heart Rate Variability in Male Rats.

ObjectiveThe purpose of this study was to develop a method for applying calibrated manual massage pressures by using commonly available, inexpensive sphygmomanometer parts and validate the use of this approach as a quantitative method of applying massage therapy to rodents.MethodsMassage pressures were monitored by using a modified neonatal blood pressure (BP) cuff attached to an aneroid gauge. Lightly anesthetized rats were stroked on the ventral abdomen for 5 minutes at pressures of 20 mm Hg and 40 mm Hg. Blood pressure was monitored noninvasively for 20 minutes following massage therapy at 5-minute intervals. Interexaminer reliability was assessed by applying 20 mm Hg and 40 mm Hg pressures to a digital scale in the presence or absence of the pressure gauge.ResultsWith the use of this method, we observed good interexaminer reliability, with intraclass coefficients of 0.989 versus 0.624 in blinded controls. In Long-Evans rats, systolic BP dropped by an average of 9.86% ± 0.27% following application of 40 mm Hg massage pressure. Similar effects were seen following 20 mm Hg pressure (6.52% ± 1.7%), although latency to effect was greater than at 40 mm Hg. Sprague-Dawley rats behaved similarly to Long-Evans rats. Low-frequency/high-frequency ratio, a widely-used index of autonomic tone in cardiovascular regulation, showed a significant increase within 5 minutes after 40 mm Hg massage pressure was applied.ConclusionsThe calibrated massage method was shown to be a reproducible method for applying massage pressures in rodents and lowering BP

The vagus nerve regulates immunometabolic homeostasis in the ovine fetus near term: impact on terminal ileum

The contribution of the vagus nerve to inflammation and glucosensing in the fetus is not understood. We hypothesized that vagotomy (Vx) will result in hyperglycemia and this will be enhanced during systemic and organ-specific inflammation. Efferent vagus nerve stimulation (VNS) should reverse this phenotype. Near-term fetal sheep (n=57) were surgically prepared with vascular catheters and ECG electrodes as control and treatment groups (lipopolysaccharide (LPS), Vx+LPS, Vx+LPS+selective efferent VNS). Fetal arterial blood samples were drawn for 7 days to profile inflammation (IL-6), insulin, blood gas and metabolism (glucose). At 54 h, a necropsy was performed; terminal ileum macrophages; CD11c (M1 phenotype) immunofluorescence was quantified to detect inflammation. Across the treatment groups, blood gas and cardiovascular changes indicated mild septicemia. At 3 h, in the LPS group IL-6 peaked; that peak was decreased in Vx+LPS400 and doubled in Vx+LPS800 group; the efferent VNS sped up the reduction of the inflammatory response profile over 54 h. M1 macrophage activity was increased in the LPS and Vx+LPS800 groups only. Glucose and insulin levels in the Vx+LPS group were respectively 1.3-fold and 2.3-fold higher vs. control at 3 h, and the efferent VNS normalized glucose levels. Complete withdrawal of vagal innervation results in a 72h delayed onset of sustained hyperglycemia for at least 54h and intermittent hyperinsulinemia. Under conditions of moderate fetal inflammation, this is related to higher levels of gut inflammation; the efferent VNS reduces the systemic inflammatory response as well as restores both the levels of glucose and terminal ileum inflammation, but not the insulin levels. Our findings reveal a novel regulatory, hormetic, role of the vagus nerve in the immunometabolic response to endotoxin in near-term fetuses

Do manual therapies have a specific autonomic effect? An overview of systematic reviews

Background The impact of manual therapy interventions on the autonomic nervous system have been largely assessed, but with heterogeneous findings regarding the direction of these effects. We conducted an overview of systematic reviews to describe if there is a specific autonomic effect elicited by manual therapy interventions, its relation with the type of technique used and the body region where the intervention was applied. Methods We conducted an overview according to a publicly registered protocol. We searched the Cochrane Database of Systematic Reviews, MEDLINE, EPISTEMONIKOS and SCOPUS, from their inception to march 2021. We included systematic reviews for which the primary aim of the intervention was to assess the autonomic effect elicited by a manual therapy intervention in either healthy or symptomatic individuals. Two authors independently applied the selection criteria, assessed risk of bias from the included reviews and extracted data. An established model of generalisation guided the data analysis and interpretation. Results We included 12 reviews (5 rated as low risk of bias according the ROBIS tool). The findings showed that manual therapies may have an effect on both sympathetic and parasympathetic systems. However, the results from included reviews were inconsistent due to differences in their methodological rigour and how the effects were measured. The reviews with a lower risk of bias could not discriminate the effects depending on the body region to which the technique was applied. Conclusion The magnitude of the specific autonomic effect elicited by manual therapies and its clinical relevance is uncertain. We point out some specific recommendations in order to improve the quality and relevance of future research in this field

用手療法の有用性に関する画像解析を用いた科学的検討

Tohoku University谷内一彦課

Spinal Manipulative Therapy Effects in Autonomic Regulation and Exercise Performance in Recreational Healthy Athletes : A Randomized Controlled Trial

7 p.Study design: A randomized, double blind, parallel groups, sham-controlled trial. Objective: The aim of this study was to analyze the acute effects of spinal manipulative therapy (SMT) on performance and autonomic modulation. Summary of background data: The use of SMT is progressively spreading from the clinical to the sporting context owing to its purported ergogenic effects. However, its effects remain unclear. Methods: Thirty-seven male recreational athletes (aged 37 ± 9 years) who had never received SMT were assigned to a sham (n = 19) or actual SMT group (n = 18). Study endpoints included autonomic modulation (heart rate variability), handgrip strength, jumping ability, and cycling performance [8-minute time trial (TT)]. Differences in custom effects between interventions were determined using magnitude-based inferences. Results: A significant and very likely lower value of a marker of sympathetic modulation, the stress score, was observed in response to actual compared with sham SMT [P = 0.007; effect size (ES) = -0.97]. A trend toward a significant and likely lower sympathetic:parasympathetic ratio (P = 0.055; ES = -0.96) and a likely higher natural logarithm of the root-mean-square differences of successive heartbeat intervals [(LnRMSSD), P = 0.12; ES = 0.36] was also found with actual SMT. Moreover, a significantly lower mean power output was observed during the TT with actual compared with sham SMT (P = 0.035; ES = -0.28). Nonsignificant (P > 0.05) and unclear or likely trivial differences (ES < 0.2) were found for the rest of endpoints, including handgrip strength, heart rate during the TT, and jump loss thereafter. Conclusion: A single pre-exercise SMT session induced an acute shift toward parasympathetic dominance and slightly impaired performance in recreational healthy athletes