Routes of tetanus toxin entrance into the central nervous system and some problems of experimental tetanus pathogenesis

Abstract

As shown by experiments on monkeys (table 1) and dogs (table 2), the main and direct route of passage of the tetanus toxin from the muscles into the spinal cord are the anterior spinal roots. This result coincides completely with the data of previous investigations on albino rats, guinea pigs, rabbits and cats [4,5,6]. After blocking the circulatory route of spread of the toxin by means of antiserum, the administration of toxin into the muscles of the posterior extremity causes a fatal ascending tetanus in dogs (Fig.2); by the time of the animal's death the antitoxin may circulate in the animal's blood (table 3). Thus, the spread of the toxin with the blood is not a required condition for the development of general fatal tetanus. However, this factor plays an important role in determining the clinical form and the outcome of the disease. Both in the monkeys (Fig.1, d, f) and in dogs (Fig. 2, f, e) there is present a phenomenon of generalization of excitation in the central nervous system upon stimulation of the extremity into which the toxin has been introduced; this phenomenon is characteristic of the ascending general tetanus and was described by the authors earlier (3). A discussion is given on the clinical forms of the disease and the route of the tetanus spread of toxin in connection with the current concepts on the pathogenesis of tetanus.