1 86 INANITION AND MALNUTRITION 



Reinke ('06) found that larvae of Salamandra maculata after successive 

 exposures to 4 per cent ether solution may live up to 152 days, but take no food. 

 The medullary tube becomes distended and thin- walled in 10 days; many cells 

 perish, others undergo mitosis (up to 80 days) . The final result is a partial regen- 

 eration of the central nervous system, which is nourished at the expense of the 

 remainder of the body, especially of the musculature, which becomes strongly 

 atrophied. Reinke further states: "Lasst man Salamanderlarven zunachst 

 hungern und futtert sie dann sehr stark mit lebenden Wurmern (Naiden), so 

 treten etwa nach einer Woche eine enorme Menge von Mitosen in fast alien 

 Organen auf, aber ganz regelmassig schubweise." 



Sugita ('18), in the underfed young albino rats previously referred to, 

 concluded from a histological study " that by starvation in the early days the 

 brain suffers much in its development in toto, but the cell division is going on 

 quite normally according to age. The growth of the cells in size is retarded and 

 the formation of myelin fibers somewhat diminished by inanition. S.o the smaller 

 weight and size of the underfed brain is due to an arrest in the growth and 

 development of the constituent neurons and not to a decrease in their number." 



Changes in Chemical Composition. — Although the chemistry of inanition is 

 outside the scope of the present work, it may be noted incidentally that the 

 brain undergoes relatively slight chemical changes during inanition. Its fat 

 (lecithin) belongs to the phosphorized lipins, which in general are very resistant 

 to starvation. In addition to those found in the papers above cited, data on 

 the chemical changes in the brain during inanition are contained in the works of 

 Aeby ('75), Pfeiffer ('87), Lukianov ('88, '89), Tonninga ('93), Voit ('94), 

 Herter ('98), Durig ('01), Roger ('07), Donaldson ('n), and Donaldson, Hatai 

 and King ('15). 



(B) Effects of Partial Inanition 



The effects upon the brain by various forms of partial inanition, including 

 dietary deficiencies in protein, fat, salts, vitamins and water, will now be 

 considered. 



Protein Deficiency. — Paltauf ('17) found the brain weight unaffected in 

 cases of human malnutritional edema and allied conditions. 



In a series of young albino rats with loss of about 30 per cent in body weight 

 (initial weight 40-101 g.) on a nearly protein-free diet of starch, suet and 

 water, Hatai ('04) found an apparent average decrease of about 5 per cent in the 

 absolute weight of the brain. No marked alteration occurs in the Nissl 

 substance. In a similar series of rats amply refed after the inanition period, 

 Hatai ('07) obtained prompt recovery in the body weight and brain weight, 

 although certain changes in the chemical composition of the brain (higher water 

 content and lower percentage of ether-alcohol extracts) still persisted. 



In albino rats held at nearly constant body weight for prolonged periods on 

 various incomplete protein diets, Osborne and Mendel ('n, '11a) held that the 

 normal proportions in the various parts of the body were maintained, excepting 

 the possibility of a continued growth of the central nervous system, for which 

 some evidence was cited. 



