PYRIDOXINE 



was confirmed by W. Antopol and K. Unna/ who claimed that hyper- 

 keratosis and acanthosis of the ears, paws and snout and an oedema 

 of the corium were characteristic of vitamin Bg deficiency, and were 

 cured by pyridoxine. Fouts et al.^ were able to show that crystalline 

 pyridoxine hydrochloride, like the crude concentrates previously 

 used, cured a microcytic hypochromic anaemia in dogs, and this was 

 confirmed by H. J. Borson and R. S. Mettier ^ and by Street et al.^ 

 The onset of anaemia is now regarded as a characteristic feature of 

 vitamin Bg deficiency, more characteristic indeed than dermatitis. 

 Remission of the anaemia in dogs brought about by pyridoxine was 

 only partial, however.^ Nervous symptoms constitute another char- 

 acteristic feature of vitamin Bg deficiency ; in chicks, these take the 

 form of various convulsive movements ^* ^ and, in rats and pigs, 

 epileptiform fits.^ Anaemia and nervous symptoms do not always 

 occur together, however, turkeys for instance exhibiting hyper- 

 excitability and convulsions, but not anaemia,^ and young ducklings, 

 severe anaemia, but not convulsions or paralysis ^^ (see also page 320). 



Rats. In rats, anaemia is not a regular sjmiptom of vitamin Bg 

 deficiency although latent erythropoiesis may be demonstrated by 

 the impaired regeneration of the red blood cells after haemorrhage.^^ 

 The total body iron and copper were significantly increased in pyri- 

 doxine-deficient rats.-^^" 



Convulsions are more characteristic of vitamin Bg deficiency in 

 this species and, when young rats were suckled by mothers maintained 

 since parturition on a vitamin Bg deficient diet, spontaneous convul- 

 sive seizures developed towards the end of lactation. ^^ These were 

 alleviated by 10 jug. of pyridoxine per day, but even 50 /Ltg. per day did 

 not protect the animals against artificially induced seizures. No 

 spontaneous seizures were observed when the mothers received 

 between 25 and 150 /xg. per day, but a high incidence of artificially 

 induced seizures occurred ; at higher levels of pyridoxine these were 

 delayed and were less severe. 



In pyridoxine deficiency, the basal metabolic rate of rats was 

 depressed,^^ and the administration of pyridoxine to vitamin Bg 

 deficient rats caused a marked acceleration in the growth rate.^^ 

 Vitamin Bg deficiency increased the amount of protein and water in 

 the body, more so in male than in female rats.^^ 



A further illustration of the close connection between pyridoxine 

 and protein metabolism, which is more fully discussed on page 330, 

 is provided by the observation that acrodynia was more severe in 

 pyridoxine-deficient rats fed a casein-rich diet than in rats fed a low 

 casein diet.^^ According to E. C. Sheppard and E. W. McHenry,^^ 

 the amount of pyridoxine in the liver, kidney and leg muscles of rats 

 fed a vitamin Bg-deficient diet for twenty-one days was independent 



318 



