EFFECTS ON THE SPINAL CORD 



197 



Donaggio ('06, '07) likewise obtained modifications of the endocellular 

 network of neurofibrillae in the nerve cells of rabbits under the combined influ- 

 ence of cold and inanition, neither factor alone appearing effective. In the 

 anterior horn cells, the fine fibrillar network presents coarser bands, possibly 

 formed by fusion of the neurofibrillae. Riva ('05, '06, '07) also found that inani- 

 tion alone usually produces relatively slight changes in the neurofibrillae of the 

 brain, spinal cord and spinal ganglia in fasting dogs and rabbits (Fig. 62). 

 The endocellular network may be considerably modified, however, in cases where 

 large vacuoles cause mechanical displacement of the neurofibrillae. The results 

 of Donaggio and Riva were confirmed and extended by Gurewitsch ('08a) in the 

 spinal cord of fasting rabbits and dogs, and by Mattioli ('io) in rabbits. The 



Fig. 62. — Nerve cells from the ventral horn of the spinal cord in the dog, showing the 

 variable changes in the neurofibrillae by Donaggio's silver method after a loss of about 50 per 

 cent in body weight from total inanition, a, a cell in which the neurofibrillae have retained 

 nearly normal structure; b, cell showing some vacuolation in the perinuclear region; c, cell with 

 disorganized neurofibrillae crowded into bundles between the numerous large cytoplasmic 

 vacuoles. (Riva '06.) 



literature on these effects of inanition upon the nerve cells in general is fully 

 reviewed by Marinesco ('09). 



In Necturus maculatiis starved 4 months the spinal cord was found nearly 

 normal by Smallwood and Rogers ('n). After 16 months, however, the spinal 

 cord appears greatly reduced in size, with atrophy especially of the gray sub- 

 stance. Changes found in the spinal ganglia will be mentioned in the next 

 chapter. In the nerve cells of the spinal cord in Triton cristatus fasting 1-6 

 months, Frankenberger ('17) described nuclear changes resembling pycnosis. 



In starved albino rats (on water only), Sundwall ('17) noted marked conges- 

 tion and edema of the spinal cord; anterior horn cells swollen, vacuolated and 

 chroma toly tic, with vesicular or pycnotic nuclei. There is diffuse degeneration 

 of the various nerve fiber tracts, especially in the posterior columns. 



Changes during Hibernation. — Since hibernation represents a special type 

 of inanition, the corresponding changes in the nerve cells of the spinal cord may 

 be separately considered. (The observations on the brain cells during hiberna- 

 tion by Querton '98,Legge '99, BaronciniandBeretta'ooand Marinesco '05 were 

 mentioned in Chapter X.) First as to the Nissl substance, no appreciable change 



