ABSTRACT
Synapses loss during aging has been related to decreased neuronal excitability and reduced electrophysiological activity in the nervous system, as well as to increased brain damage. Those physiological and biochemical alterations have been related to the oxidative stress increase associated with old age. The main substrate of lipid peroxidation (LPX) in the central and peripheral nervous systems are the myelin sheaths, and their damage generates a delayed nerve conduction velocity. However, studies in which the neural conduction velocity is related to changes in the redox state are still lacking. Therefore, our aim was to correlate the sensory neural pathways delay in healthy geriatric Rhesus monkeys (Macaca mulatta) with the oxidative stress associated with physiological aging. Twenty-four monkeys were divided into four groups according to age and gender. Auditory, visual, and somatosensory evoked potentials were obtained. Superoxide dismutase, catalase, and glutathione peroxidase enzymatic activity, as well as LPX, were determined from blood samples. Our results showed significant differences between the older and younger age groups in all neural generators of the different sensory pathways evaluated, along with an increase in LPX and the antioxidant enzymatic activities. It suggests that, even though the enzymatic activity was found to be higher in older monkeys, probably as a compensatory effect, it was not enough to avoid LPX damage and the declined electric activity associated with age.
Subject(s)
Aging/physiology , Evoked Potentials, Auditory/physiology , Evoked Potentials, Somatosensory/physiology , Evoked Potentials, Visual/physiology , Lipid Peroxidation/physiology , Nervous System , Animals , Female , Glutathione Peroxidase/metabolism , Macaca mulatta , Male , Nervous System/enzymology , Nervous System/metabolism , Nervous System/physiopathology , Neural Conduction/physiology , Oxidation-Reduction , Oxidative Stress , Sensation/physiology , Superoxide Dismutase/metabolismABSTRACT
BACKGROUND: Synapses loss during aging is associated to neurophysiologic alterations that impair organism's health span, thus making the study and prevention of sensory decline relevant for healthy aging and welfare. Therefore the aim of this study was to obtain normative data related to the electrophysiological responses of the different neurosensory components in the visual, auditory and somatosensory pathways in healthy geriatric rhesus monkeys in captivity. METHODS: Twenty-four rhesus monkeys were divided in two groups: (i) Geriatric monkeys, 20-30 years of age, and (ii) Young monkeys, 7 years of age. Evoked potentials were obtained from the visual, auditory and somatosensory pathways. RESULTS: Regardless the sensory pathways evaluated, a significant delay in nerve conduction was observed in the geriatric group in comparison to the young group. CONCLUSIONS: Evoked potentials allowed identifying changes generated during aging in rhesus monkeys and normative data for this species were obtained.
Subject(s)
Aging/physiology , Auditory Pathways/physiology , Macaca mulatta/physiology , Somatosensory Disorders/veterinary , Visual Pathways/physiology , Animals , Electric Conductivity , Evoked Potentials, Auditory, Brain Stem , Evoked Potentials, Somatosensory , Evoked Potentials, Visual , Female , Male , Neural Conduction/physiology , Somatosensory Disorders/physiopathology , Tibial Nerve/physiologyABSTRACT
BACKGROUND: We describe two clinical cases and examine the effects of piracetam on the brainstem auditory response in infantile female rhesus monkeys (Macaca mulatta). RESULTS: We found that the interwave intervals show a greater reduction in a 3-year-old rhesus monkey compared to a 1-year-old rhesus monkey. DISCUSSION: In this report, we discuss the significance of these observations.
