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Background: The detailed pathophysiology of limb coldness in multiple system atrophy (MSA) is unknown., Methods: We evaluated cutaneous vasomotor neural function in 18 MSA patients with or without limb coldness, and in 20 healthy volunteers as controls. We measured resting skin sympathetic nerve activity (SSNA) and spontaneous changes of the sympathetic skin response (SSR) and skin blood flow (skin vasomotor reflex: SVR), as well as SVR and reflex changes of SSNA after electrical stimulation. The parameters investigated were the SSNA frequency at rest, amplitude of SSNA reflex bursts, absolute decrease and percent reduction of SVR, recovery time, and skin blood flow velocity., Results: Both the resting frequency of SSNA and the amplitude of SSNA reflex bursts were significantly lower in the MSA group than the control group (p<0.001 and p<0.05, respectively). There were no significant differences between the two groups with regard to the absolute decrease or percent reduction of SVR volume. The recovery time showed no significant difference between all MSA patients and control groups, but it was significantly prolonged in six MSA patients with limb coldness compared with that in the control group and that in MSA patients without limb coldness (p<0.01). The skin blood flow velocity was significantly slower in the MSA group than in the control group (p<0.001)., Conclusion: In MSA patients, limb coldness might occur due to impairments of the peripheral circulation based on prolongation of vasoconstriction and a decrease of skin blood flow velocity secondary to combined pre- and postganglionic skin vasomotor dysfunction., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: In amyotrophic lateral sclerosis (ALS), not only impairment of motor neurons but also impairment of the autonomic nervous system has been demonstrated by previous physiological studies. Several investigators have reported a correlation between autonomic dysfunction and respiratory dysfunction in ALS. This study analyzed the relation between parameters of respiratory function and muscle sympathetic nerve activity (MSNA) in a large number of ALS patients., Methods: In 50 patients with ALS (mean age (SD): 62.1 (11.7) years), MSNA, heart rate (HR), and blood pressure (BP) were recorded simultaneously. The arterial oxygen content (PaO2), arterial carbon dioxide content (PaCO2), and forced vital capacity expressed as a percentage of the predicted value for healthy controls (%VC) were determined as parameters of respiratory function., Results: There were no significant correlations between MSNA and PaO2, PaCO2, %VC, or the disability score. Analysis of chronological changes in 14 patients examined twice showed that the disability score and PaCO2 were significantly increased, and %VC was significantly more decreased at the second examination compared with the first examination (p<0.01 and p<0.05, respectively). In contrast, HR, BP, burst rate of MSNA, and age-adjusted MSNA exhibited no significant changes between the first and second examinations., Conclusions: These findings show that gradual deterioration of respiratory function in ALS patients is not associated with changes of quantitative MSNA parameters, which may suggest that abnormality of the autonomic nervous system is a primary feature of ALS., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The purpose of this study was to evaluate the clinical and pathological features in patients with progressive-type familial amyloidotic polyneuropathy (FAP) using autopsy and biopsy specimens. A proband is a 33-year-old man with FAP type I who developed motor, sensory and autonomic impairments with neuropathy, heart failure, and anorexia. Genetic findings of transthyretin (TTR) revealed G to A transition in codon 54 causing a rare mutation of TTR Lys54. He died of pneumonia and severe cardiac failure 4 years after onset. Autopsy showed heavy amyloid deposition in the heart, peripheral nerves, thyroid, skin, fat tissue, prostate and testis, moderate in the sympathetic nerve trunk, vagal nerve, celiac plexus, pelvic plexus, bladder, gastrointestinal tract, tongue, pancreas, lung, pituitary, blood vessel, gall bladder, adrenals and muscles, and free in the central nervous system, liver, kidney and spleen. Sural nerve biopsy in a sibling confirmed TTR amyloidosis immunohistochemically. Electronmicroscopic findings of amyloid fibrils were similar to that of FAP Met30. Immunoelectronmicroscopic findings indicated the relationship between amyloid fibrils or non-fibrillar structure and collagen fibers. The distribution of amyloid deposition, heavy in the heart and lacking in the kidney, is a characteristic feature and reflected severity of FAP with TTR Lys54.

To confirm correlations between muscle sympathetic nerve activity (MSNA) and patients' chronological data, we selected 40 consecutive patients with sporadic amyotrophic lateral sclerosis (ALS) recorded by similar methods. MSNA at rest was quantified as the number of sympathetic bursts per 100 heartbeats and as the value expressed as a percentage of the predicted value based on control data. Twelve patients who underwent recordings of MSNA twice at intervals of 6 months or more showed marked decreases in MSNA amplitudes and frequencies between examinations. There was a slightly positive correlation between the frequency of MSNA and age, though younger patients exhibited higher values of MSNA than older patients. The standardized value of MSNA correlated negatively with disease duration and disability levels (p<0.01, 0.05, respectively), but several patients with duration shorter than 12 months showed low values of MSNA. Twelve patients who underwent repeated recordings of MSNA showed a significant decrease in the mean standardized value of MSNA (102.6+/-24.9%) at the second examination, compared to the value (114.3+/-18.9%) at the first one. In ALS, sympathetic outflow to muscles tends to increase initially and then decrease with increasing age and duration. This pattern may be similar to chronological changes at motor neurons.