Ayumi Fukazawa , Norio Hotta , Hoda Yeganehjoo , Amane Hori , Han-Kyul Kim , Gary A. Iwamoto , Scott A. Smith , Wanpen Vongpatanasin , Masaki Mizuno
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引用次数: 0
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder. It is characterized by synaptic loss and the increase of amyloid β (Aβ) in the brain often detrimentally affecting function. Brainstem is the key central integration site for sensory input from working skeletal muscle. Stimulation of skeletal muscle afferent fibers during muscle contraction increases blood pressure. However, whether AD alters or preserves the central processing of peripheral sensory afferent signals remains to be elucidated. Thus, we tested the hypothesis that the magnitude of the pressor response is functionally altered in intracerebroventricular-streptozotocin injected rats (ICV-STZ). Streptozotocin (3 mg/kg) was intracerebroventricularly injected into the lateral ventricle of male Sprague–Dawley rats. In parallel, a separate group of rats were treated with ICV saline as a vehicle control. Spatial learning and memory function were assessed using the Morris Water Maze behavioral test. Results demonstrate that ICV-STZ rats had a significantly longer time to reach a target platform compared to controls (P = 0.0046). ICV-STZ injection also significantly increased brainstem Aβ1–40 (P = 0.0082), but not Aβ1–42 (P = 0.0744). Further, the peak pressor and cardioaccelerator responses to tibial nerve stimulation were significantly attenuated in ICV-STZ rats compared to controls (ΔMAP: P = 0.0003, ΔHR: P = 0.0035). The findings suggest that the cardiovascular responses to electrical stimulation of sensory afferents are blunted in ICV-STZ rats.
期刊介绍:
This is an international journal with broad coverage of all aspects of the autonomic nervous system in man and animals. The main areas of interest include the innervation of blood vessels and viscera, autonomic ganglia, efferent and afferent autonomic pathways, and autonomic nuclei and pathways in the central nervous system.
The Editors will consider papers that deal with any aspect of the autonomic nervous system, including structure, physiology, pharmacology, biochemistry, development, evolution, ageing, behavioural aspects, integrative role and influence on emotional and physical states of the body. Interdisciplinary studies will be encouraged. Studies dealing with human pathology will be also welcome.