'9°4 



ilWUBOOK OF PHYSIOLOGY 



NEUROPHYSIOLOGY III 



has been denied by Olcott (197) and Pappenheimer 

 (201). There is also disagreement as to the presence 

 of alterations of the nerve endings in the muscles and 

 in the central synapses (50, 271)' 



Wry likely the degeneration of the posterior column 

 and posterior roots fibers in the ral is directly related 

 to the vitamin E deficiency, but there is no evidence 

 that the other neuropathological findings in this 

 condition can be attributed directly to the tocopherol 

 deficiency. Especially confusing is the situation with 

 respect to vitamin E and certain neurological dis- 

 turbances in man. After initial reports of success in 

 the treatment of amyotrophic lateral sclerosis and 

 progressive muscular atrophy by administration of 

 vitamin E, most of the authors deny effectiveness of 

 this treatment (cf. 162, p. 729). 



NONDEFICITARY ABNORMALITIES OF 

 NUTRITIONAL ORIGIN 



So far we have been concerned with alterations in 

 nervous function and behavior resulting from the 

 lack or relative deficiency of certain nutrients. Ab- 

 normalities may be produced also by the presence of 

 substances in the diet which a) are mistaken for 

 harmless food but which are actually toxic (e.g. 

 some mushrooms), b) are not inherently toxic but 

 are made so by the processing of foods (e.g. agenized 

 flour producing canine hysteria), c) represent normal 

 foodstuffs not toxic unless eaten in large amounts 

 under conditions of unbalanced diet (e.g. lathyrus 

 peas and other leguminous seeds), or d) are not toxic 

 to normal individuals but produce nervous disturb- 

 ances in persons with specific metabolic faults (e.g. 

 the amino acid phenylalanine in persons lacking 

 enzymes necessary for its normal metabolism). 



Mushroom Poisoning 



Ingestion of the bun bodies ol certain species oi 

 the mushroom genus Amanita {A. muscaria, .1. panthe- 

 rina), containing bufotenin as the active substance, 

 produces hallucinations and its use .is an intoxicant 

 among some Siberian tribes has long been known. 

 In Mexico the 'sacred fungus,' teonanacatl, identified 

 as Panaeolus campanulatus var. tphinctrinus, lias served for 

 centuries a similai purpose (67); and recently fungi 

 belonging to other genera wen- described as having 

 hallucinogenic properties, 



Canine Hysteria 



The term has been applied in Great Britain to a 

 pathological condition in clogs characterized l>\ 

 striking nervous symptoms, including paroxysmal 

 attacks of hvperexcitability, running and barking or 

 howling, manifestations of faultv vision, and clonic 

 convulsions. Urination and defecation occur fre- 

 quently during the convulsions, along with secretion 

 of mucous saliva. The animals seem at this time 

 indifferent to injury. They mav appear normal be- 

 tween attacks which are often precipitated by ex- 

 ternal stimuli, such as noise or light. In the United 

 States, the disease has been called "fright disease,' 

 'running fits,' 'enzootic hysteria' and 'hyperkinesia.' 

 This nervous disturbance is definitely dietary in 

 origin (8, 169, 180, 284), appearing in dogs fed a 

 diet containing agenized flour (166, 168, 179), the 

 "toxic' substance in which was finally identified as 

 methionine sulphoxamine (13, 14, 34, 218). This 

 substance is a metabolic antagonist (102) which 

 interferes with the enzyme systems synthesizing 

 glutamine in the brain and with the glutamyl trans- 

 ferase (200). It also interferes with the formation of 

 bound acetylcholine in the cerebral cortex (274). 

 It is toxic to rabbits (215) and ferrets (■]■>,), but seems 

 to possess little or no toxicity for some animal species 

 (rat); and there is no evidence of untoward effects 

 of the agene-treated flour on human nervous func- 

 tion (62). 



The EEG tracings of dogs receiving a diet contain- 

 ing wheat gluten (189, 190) or wheat flour treated 

 with nitrogen trichloride (245 1 showed alterations as 

 early as 3 days after the beginning of the diet before 

 any clinical abnormality was noticed. In view of the 

 similarity between the clcctroeneephalographic trac- 

 ings obtained in these dogs and those in human 

 epilepsy, the name 'canine epilepsy' was suggested. 

 Cats seem lo be more resisiant to agenized flour 

 than do'^s. Monkeys, although not developing con- 

 vulsions, show a syndrome characterized by tremor 

 of the extremities and weakness of the hind limbs 

 which develop within ", days of maintenance on the 

 experimental diet 



Lathyrism 



The name designates a form of epidemic spastic 

 paraplegia which develops in man in association with 

 excessive consumption ol lathyrus peas (especially 



/ L. 1 •' and /.. clymenum). The disease itself 



has been known since ancient times, and Hippoc- 



rates described the association of weakness of the 



