The paralysis of autonomic ganglia, with special reference to the therapeutic effects of ganglion-blocking drugs / by W.D.M. Paton.

  • William Paton
Date:
[1951?]
Catalogue details

Licence: In copyright

Credit: The paralysis of autonomic ganglia, with special reference to the therapeutic effects of ganglion-blocking drugs / by W.D.M. Paton. Source: Wellcome Collection.

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    Corresponding to this, after a suitable dose of hexa- methonium, a pre-ganglionically excited tetanus of the nictitating membrane, which previously produced a well- sustained contraction, now produces a spiky contraction, which at first is not far in height from the control, but which cannot now be maintained. Thus, as stimulation is prolonged, the ganglion becomes more sensitive to the blocking agent. In the same way, if high rates of stimulation are used the ganglion is more sensitive to the blocking agent than with slower rates ; this fact can be made use of in assaying small amounts of the drug. These effects, by which intense or prolonged activity alters the state of the ganglion and increases the action of pentamethonium or of hexamethonium, are relevant clinically. They may explain why it has been possible to give doses relieving hypertension or ulcer pain with¬ out paralysing, say, the normal function of the small intestine and bladder. For if one makes the assumption that in hypertension the vasomotor ganglia are hyper¬ active (or, in ulcer, the ganglia of the stomach), then it should be possible to diminish this overactivity considerably before interfering with the quieter-paced normal function. Further, if this is true then the proportion of side- actions to therapeutic effect will be least in the truly functional disorders. On the other hand, in those con¬ ditions in which there is no specific overactivity of this sort, in which any effect produced is due to the paralysis of some normal function, side-actions may be expected to be more severe. It may be possible, therefore, to infer from the intensity of side-effects whether the action of hexamethonium in a given disease is through the relief of an abnormal autonomic pressure, or whether it is simply that the reduction of a normal autonomic function happens to provide some palliation of the disorder. Effects of Hexamethonium in Man The first trials (actually carried out with penta¬ methonium) (Organe, Paton, and Zaimis, 1949) served to establish the primary fact that the order of activity of these drugs was roughly the same in man as in the cat (in which most of the analysis of their action was done). Since then much valuable information has been gained, chiefly in the two fields of cardiovascular and gastric function.
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