A text-book of pharmacology and therapeutics; or, The action of drugs in health and disease, . other hand, was not transmitted to the motor cells, although these were shown by the first part of the experiment to be capable of stimulation. This experiment is best interpreted by supposing that the anses- thetics act first on the first synapse in the cord that is met by an afferent impulse. Later, however, the motor cells or their synapses are also paralyzed, as is shown by stimulation of the cord having no effect, even when the respiration is still stimulation of the cerebral m
A text-book of pharmacology and therapeutics; or, The action of drugs in health and disease, . other hand, was not transmitted to the motor cells, although these were shown by the first part of the experiment to be capable of stimulation. This experiment is best interpreted by supposing that the anses- thetics act first on the first synapse in the cord that is met by an afferent impulse. Later, however, the motor cells or their synapses are also paralyzed, as is shown by stimulation of the cord having no effect, even when the respiration is still stimulation of the cerebral motor areas produces movement for some time after sensation has been lost, but as the anaesthesia becomes deeper, their irri-tability disappears. Finally the medullary centres are also paralyzed by the anses- thetic. There is some evidence that they are first stimulated directly by chloroform and ether (page 200). The medullary centres are liable to be affected by reflex stimulation up to the moment at which they cease to send out impulses, for the respiratory centre responds to stimulation. Diagram of the spinal cord:A-B part of the cord exposed tothe action of chloroform; B-Cpart unaffected. A sensory im-pression traveling by the pos-terior root fibre D docs not elicita reflex niovcmcnt, but one reach-ing the cord through the unaf-fected root E causes refleximpulses, which may be sentout by the motor cells F, F inthe unaffected area, or by F, Fin the poisoned area. The ceilsof the anterior horns F, F andthe dendrites surrounding themare. therefore, intact after thereflex arc is interrupted at someother point. 200 SUBSTANCES ACTING AFTER ABSORPTION of the superior laryiio;eal nerve as long as the respiration is possible that the motor cells are not directly paralyzed by thedrug, l)ut can only send out impulses received from the sensory cells,and that the paralysis of these is the cause of the asphyxia. Shortly stated, the direct action of chloroform and ether on th
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttherapeutics, bookyea
