Tissue receptors. Historical scope. Modern view. Perspectives

A brief history of Russian research on the autonomic nervous system

The first information on the structure and function of the autonomic nervous system dates back to the time of Galen (second century), while the beginning of the study of the autonomic nervous system in Russia can be traced back to the mid-19th century. This review is devoted to the professional achievements of Russian researchers in the 19th and 20th centuries who were active in the field of the autonomic nervous system at different stages of the development of neuromorphology and neurophysiology. In addition, recent achievements of modern Russian researchers active in this domain are also highlighted. This review is mainly devoted to research on the autonomic nervous system in Russia, but it would be unfair not to mention the scientists who made a significant contribution to this field of science and worked in the republics of the former USSR. Russian morphology and physiology developed under the significant influence of well-known western scientific schools. I sincerely hope that cooperation between Russian and foreign colleagues will continue and will be fruitful for global science.

Responses of upper airway, intercostal and diaphragm muscle activity to stimulation of oesophageal afferents in dogs

The effects of oesophageal distension on respiratory patterns and the moving average electromyogram (e.m.g.) activity of three upper airway muscles--the alae nasi, the genioglossus, and the posterior cricoarytenoid--and four chest wall muscles--the costal and crural diaphragm and the inspiratory and expiratory intercostals--were examined in ten anaesthetized, tracheostomized, spontaneously breathing dogs. Distension was produced by inflations of a balloon placed in the middle part of the thoracic oesophagus with volumes of air ranging from 50 to 200 ml. Oesophageal distension increased respiratory frequency, mainly due to a significant shortening of the expiratory time. Activity of both the costal and crural parts of the diaphragm was inhibited with oesophageal distension, whereas that of the inspiratory intercostal muscles increased, tending to maintain a near-normal tidal volume and end-tidal CO2. Phasic inspiratory activity of all three upper airway muscles increased in response to oesophageal distension, as did the activity of the expiratory intercostal muscles. The changes in the breathing pattern and the electrical activity of all muscles in response to oesophageal distension were immediate, occurring during the first breath after the balloon was inflated. The responses were graded, so that increases in the volume of the oesophageal balloon progressively increased the activity of the upper airway and intercostal muscles, and decreased diaphragm activity. Bilateral vagotomy abolished the effects of oesophageal distension on upper airway and chest wall muscle activity, suggesting that vagal afferents constitute the major pathway for the reflex.