scholarly journals Endurance exercise: a model of physiological integration

2021 ◽  
Vol 38 (5) ◽  
pp. 351-357
Author(s):  
Francisco Javier Calderón-Montero ◽  
Juan José Ramos-Álvarez ◽  
Irma Lorenzo Capella
Keyword(s):  
Nervous System ◽  
Endurance Exercise ◽  
Feedback System ◽  
Physiological Integration ◽  
Strength Development ◽  
Electrolyte Balance ◽  
Control Mechanisms ◽  
Moderate Degree ◽  
Central Command ◽  
Anatomical Entity

Endurance exercise is a model of physiological integration. There is no other animal activity in which cardiovascular, respiratory, metabolic-endocrine and neuromuscular functions are activated at the same time. Even apparently, silent functions are essential during exercise (digestive, renal). During long-term exercise, the absorption of water and carbohydrates is a determining factor in performance. Kidney function plays a fundamental role in trying to preserve the hydro-electrolyte balance during exercise. In this work we present an integrative physiological perspective during dynamic exercise (mobilization of a large muscle mass with a low to moderate degree of strength development), both from the point of view of health and performance. The response of the heart rate in the first moments of exercise is a good example of the feedforward mechanism. Overall, the nervous system has two control mechanisms: feedforward and feedback. These depend on the central command, a more functional than anatomical entity. The feedforward system allows to immediately start the cardiovascular and respiratory systems. This mechanism is important because it activates the organism to overcome resting state. The feedback system is equally important because it allows the central command to receive the necessary information to “order” the appropriate response according to the intensity of the exercise. The information for retrocontrol comes from various receptors located in: the muscles, the respiratory system and the cardiovascular system. It is complex information that the central nervous system processes with exquisite precision, as can be seen in in endurance exercise.

scholarly journals Angiotensin-Converting Enzyme 2 (ACE2) as a Potential Diagnostic and Prognostic Biomarker for Chronic Inflammatory Lung Diseases

Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1054
Author(s):  
Dejan Marčetić ◽  
Miroslav Samaržija ◽  
Andrea Vukić Dugac ◽  
Jelena Knežević
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Lung Diseases ◽  
Balance Control ◽  
Chronic Obstructive ◽  
Electrolyte Balance ◽  
Control Mechanisms ◽  
Pathophysiological Mechanism ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme 2 ◽  
Potential Biomarker

Chronic inflammatory lung diseases are characterized by uncontrolled immune response in the airways as their main pathophysiological manifestation. The lack of specific diagnostic and therapeutic biomarkers for many pulmonary diseases represents a major challenge for pulmonologists. The majority of the currently approved therapeutic approaches are focused on achieving disease remission, although there is no guarantee of complete recovery. It is known that angiotensin-converting enzyme 2 (ACE2), an important counter-regulatory component of the renin–angiotensin–aldosterone system (RAAS), is expressed in the airways. It has been shown that ACE2 plays a role in systemic regulation of the cardiovascular and renal systems, lungs and liver by acting on blood pressure, electrolyte balance control mechanisms and inflammation. Its protective role in the lungs has also been presented, but the exact pathophysiological mechanism of action is still elusive. The aim of this study is to review and discuss recent findings about ACE2, including its potential role in the pathophysiology of chronic inflammatory lung diseases:, i.e., chronic obstructive pulmonary disease, asthma, and pulmonary hypertension. Additionally, in the light of the coronavirus 2019 disease (COVID-19), we will discuss the role of ACE2 in the pathophysiology of this disease, mainly represented by different grades of pulmonary problems. We believe that these insights will open up new perspectives for the future use of ACE2 as a potential biomarker for early diagnosis and monitoring of chronic inflammatory lung diseases.

scholarly journals Cerebral hemispheres – cerebellum – kidney interaction in patients with acute cerebral ischemia

2021 ◽  
Vol 26 (1) ◽  
pp. 90-98
Author(s):  
O.M. Kononets ◽  
O.V. Tkachenko ◽  
O.O. Kamenetska
Keyword(s):  
Nervous System ◽  
Ischemic Stroke ◽  
Brain Magnetic Resonance Imaging ◽  
Environmental Parameters ◽  
The Body ◽  
Electrolyte Balance ◽  
Vector Correlation ◽  
Vertebrobasilar System ◽  
Acute Cerebral Ischemia ◽  
The Right

The nervous system, in particular the autonomic one, is well known to constantly regulate the internal functioning of the body, adapting it to changeable external and internal environmental parameters. In particular, there is a close multiple-vector correlation between the nervous system and the kidneys. The aim of this study was to specify the mechanisms, clinical and paraclinical characteristics of the concomitant lesions of the nervous system and the kidneys in patients with acute stroke. This paper presents the case report of 215 patients, aged 70 ± 8.44, who suffered from ischemic stroke. Among them, we examined 144 women and 71 men. The patients underwent a comprehensive examination, including a detailed clinical and neurological check-up (evaluating the patients’ condition severity with the National Institutes of Health Stroke Scale (NIHSS) and the Barthel index on admission and on the 21st day of the disease), laboratory analysis (electrolyte balance, nitrogen metabolism (on admission and on the 21st day of the disease) and instrumental examination (CT scan of the brain, the follow-up brain magnetic resonance imaging). The statistical methods were used to analyze the data. In the 1st day of the disease, all the surveyed patients with right hemispheric carotid stroke and the overwhelming majority of the patients with left hemispheric carotid stroke and ischemic stroke in the vertebrobasilar system had cerebral renal syndrome, represented by renal concentration-filtration dysfunction, accompanied by the reduced glomerular filtration rate. A reliable relationship was found between the renal concentration and filtration function and the right hemispheric ischemic focus in patients with ischemic stroke, the characteristics are to be specified.

Central Command Neurons of the Sympathetic Nervous System: Basis of the Fight-or-Flight Response

Science ◽  
1995 ◽  
Vol 270 (5236) ◽  
pp. 644-646 ◽  
Author(s):  
A. S. P. Jansen ◽  
X. V. Nguyen ◽  
V. Karpitskiy ◽  
T. C. Mettenleiter ◽  
A. D. Loewy
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Central Command ◽  
Command Neurons ◽  
Flight Response ◽  
Sympathetic Nervous ◽  
Fight Or Flight Response ◽  
Fight Or Flight

Mechanisms for generating temporal filters in the electrosensory system

1999 ◽  
Vol 202 (10) ◽  
pp. 1281-1289 ◽  
Author(s):  
G.J. Rose ◽  
E.S. Fortune
Keyword(s):  
Nervous System ◽  
Discharge Rate ◽  
Temporal Structure ◽  
Sensory Information ◽  
Gain Control ◽  
Membrane Properties ◽  
Control Mechanisms ◽  
Temporal Features ◽  
Level Of Activity ◽  
The Central Nervous System

Temporal patterns of sensory information are important cues in behaviors ranging from spatial analyses to communication. Neural representations of the temporal structure of sensory signals include fluctuations in the discharge rate of neurons over time (peripheral nervous system) and the differential level of activity in neurons tuned to particular temporal features (temporal filters in the central nervous system). This paper presents our current understanding of the mechanisms responsible for the transformations between these representations in electric fish of the genus Eigenmannia. The roles of passive and active membrane properties of neurons, and frequency-dependent gain-control mechanisms are discussed.

Iodoantipyrine and Rb86 Cl uptake by brain, cord, and sciatic nerve in the rat

1963 ◽  
Vol 204 (2) ◽  
pp. 327-329 ◽  
Author(s):  
Morris J. Mandel ◽  
Francesco Arcidiacono ◽  
Leo A. Sapirstein
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Nervous System ◽  
Sciatic Nerve ◽  
Peripheral Nerve ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Anatomical Entity ◽  
Nerve Blood Flow ◽  
The Brain

Rb86 and Iodo131 antipyrine were injected together by vein in rats. The brain, spinal cord, and nerve contents of each label were measured 30 or 60 sec later. Iodoantipyrine values were used to calculate blood flow to these portions of the nervous system. The ratio of Rb86 to iodoantipyrine uptake was used as an index of the efficacy of the hematoneural barrier. The barrier is most complete in the brain, less complete in the spinal cord, and absent in peripheral nerve. Blood flow values per gram are: brain .41 ml/g min; cord .28 ml/g min, and nerve .11 ml/g min. It is suggested that the blood-brain barrier is an anatomical entity rather than a functional one.

Adaptability of innate motor patterns and motor control mechanisms

1986 ◽  
Vol 9 (4) ◽  
pp. 585-599 ◽  
Author(s):  
M. B. Berkinblit ◽  
A. G. Feldman ◽  
O. I. Fukson
Keyword(s):  
Nervous System ◽  
Motor Control ◽  
Degrees Of Freedom ◽  
Behavioral Plasticity ◽  
Motor Behavior ◽  
Voluntary Control ◽  
Control Mechanisms ◽  
Motor Equivalence ◽  
Motor Patterns ◽  
Dynamic Components

AbstractThe following factors underlying behavioral plasticity are discussed: (1) reflex adaptability and its role in the voluntary control of movement, (2) degrees of freedom and motor equivalence, and (3) the problem of the discrete organization of motor behavior. Our discussion concerns a variety of innate motor patterns, with emphasis on the wiping reflex in the frog.It is proposed that central regulation of stretch reflex thresholds governs voluntary control over muscle force and length. This suggestion is an integral part of the equilibrium-point hypothesis, two versions of which are compared.Kinematic analysis of the wiping reflex in the spinal frog has shown that each stimulated skin site is associated with a group of different but equally effective trajectories directed to the target site. Such phenomena reflect the principle of motor equivalence -the capacity of the neuronal structures responsible for movement to select one or another of a set of possible trajectories leading to the goal. Redundancy of degrees of freedom at the neuronal level as well as at the mechanical level of the body's joints makes motor equivalence possible. This sort of equivalence accommodates the overall flexibility of motor behavior.An integrated behavioral act or a single movement consists of dynamic components. We distinguish six components for the wiping reflex, each associated with a certain functional goal, specific body positions, and motor-equivalent movement patterns. The nervous system can combine the available components in various ways in forming integrated behavioral sequences. The significance of command neuronal organization is discussed with respect to (1) the combinatory strategy of the nervous system and (2) the relation between continuous and discrete forms of motor control. We conclude that voluntary movements are effected by the central nervous system with the help of the mechanisms that underlie the variability and modifiability of innate motor patterns.

scholarly journals Distinct Proximal and Distal Corticospinal Signals Embed Limb Dynamics Through the Modulation of Stiffness

2019 ◽  
Author(s):  
R. L. Hardesty ◽  
P. H. Ellaway ◽  
V. Gritsenko
Keyword(s):  
Nervous System ◽  
Physical Properties ◽  
Neural Control ◽  
Primary Motor Cortex ◽  
Equations Of Motion ◽  
Task Demands ◽  
The Body ◽  
Control Mechanisms ◽  
Neural Signals ◽  
Limb Dynamics

AbstractThe complexities of the human musculoskeletal system and its interactions with the environment creates a difficult challenge for the neural control of movement. The consensus is that the nervous system solves this challenge by embedding the dynamical properties of the body and the environment. However, the modality of control signals and how they are generated appropriately for the task demands are a matter of active debate. We used transcranial magnetic stimulation over the primary motor cortex to show that the excitability of the corticospinal tract is modulated to compensate for limb dynamics during reaching tasks in humans. Surprisingly, few profiles of corticospinal modulation in some muscles and conditions reflected Newtonian parameters of movement, such as kinematics or active torques. Instead, the overall corticospinal excitability was differentially modulated in proximal and distal muscles, which corresponded to different stiffness at proximal and distal joints. This suggests that the descending corticospinal signal determines the proximal and distal impedance of the arm for independent functional control of reaching and grasping.Significance StatementThe nervous system integrates both the physical properties of the human body and the environment to create a rich repertoire of actions. How these calculations are happening remains poorly understood. Neural activity is known to be correlated with different variables from the Newtonian equations of motion that describe forces acting on the body. In contrast, our data show that the overall activity of the descending neural signals is less related to the individual Newtonian variables and more related to limb impedance. We show that the physical properties of the arm are controlled by two distinct proximal and distal descending neural signals modulating components of limb stiffness. This identifies distinct neural control mechanisms for the transport and manipulation actions of reach.

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