心搏リズムと自律神経機能—心臓・血管反射を指標とした自律神経機能検査法の検討

CARDIAC RHYTHM AND THE FUNCTIONS OF THE AUTONOMIC NERVOUS SYSTEM:Studies on the examination of the functions of the autonomic nervous system based on the cardiovascular responses

I．緒言

　心臓および血管の生理的機能は種々の因子によつて影響をうけるが，なかでも自律神経系の影響がきわめて重要であることは，論をまたない。自律神経系の機能状況を直接測定するには，該神経系のインパルスを電気生理学的方法によつて測定するよりほかに方法はないが，このような方法は臨床的に応用することができない。したがつて当然該神経系の奏効臓器の機能を通して測定するしか道はない。しかるに奏効臓器の機能を左右する因子は，自律神経のみではない。そこに自律神経機能検査法の困難性がある。

　この困難性の解決のひとつの方法として，心臓または血管系に反射的に影響するきわめて微小の刺激を与えて，それによつて生ずる心臓または血管系の反応の程度を測定すれば，かかる反射系の遠心路は自律神経系を経由するから，その自律神経系の反応性を測定することができることになる。このさい与える刺激は，自律神経系の況状を乱さない小さい刺激であり，かつできるだけ一定の強度の刺激であることが望ましいわけである。

It was stressed by Anrep and others that the re-spiratory arrhythmia of the dog is influenced domi-nantly by the vagal nerve. Furthermore, Matsuda and his co-workers confirmed that the vagal tone, both nervously and pharmacologically, played the dominant role in the causation of the respiratory arrhythmia in both men and animals. From these findings, this author concluded that the degree of respiratory arrhythmia might indicate the vagal tone itself.

We found, however, that there was no relation-ship between the respiratory arrhythmia and such phenomena as salivary secretion, sublingual tempera-ture, electrical resistance of skin, heart rate, blood pressure, etc. It was also noticed that the whole state of the autonomic nervous system must not be judged by the function tests of such phenomena as mentioned above. It seemed that Wanger's method, by which the physiological states of autonomic ner-vous system were summarized by means of too many function tests, was erroneous.

The author made some pharmacodynamic examina-tions of the autonomic nervous system, that is, adrenaline and atropine tests, as in the past. It was found that the reactions of each organ to these tests varied with the process of time respectively and there were no relationships among the values of above mentioned phenomena at each time of the reaction process and the pharmacodynamic tests, except one between heart rate and respiatory arrhythmia. As the results of these examinations, it is necessary to indicate the time when the measurements have been made.

As described abwe, although the functions of autonomic nervous system are very complicated, it may be assumed that their physiological and clinical significance should be discussed from a point of view of cardiovascular responses provided an adequate stimulus is given to the cardiovascular system.