(132) CJHA-PTER V 121? 



HypER?IASIA 

 * 1 



Xlith Virchor; , \ve will term hyperplasia all abnormal qtian- 

 titive increase, whichx is proitioea by oell-divisioi^ . 



A sharp, unbroken line raajr not be drawn betv^een the formal 

 spheres of hypertrophy and hyperplasia v/ithout dissolving many 

 of the "natural" groups of abnormal tissue forwations which we 

 have already established. We thus term as "natural", those 

 groups of which the memberB aro Identified as belonging together 

 not on account of onlv one ohnreoteristic, but of several,- his- 

 tologlo, ontogenetic, etiologio. In order ^ot to break up 

 groups of this kind, we spoke in the previous chapter of some 

 abnormal tissue formations, which are produced not only by cell 

 growth, but also, under ttbr'.'i'iin Qircumstances , by cell -division. 

 Reference Is mada to the places here concerned (especially pp. 

 86-109), In the prfjsent chapter we will have to consider a thor- 

 oughly uniform material, since only forms of disease will be dis- 

 cussed in it, which are produced by abnormal cell-division. 



In the phenomena termed hypertrophies, it was often left 

 undecided whether they are produced by the supplying of nutri- 

 tive substances and "over-nutrition", or were accompanied at 

 least by processes of this kind and, not infrequently, it had to 

 be stated as absolutely impossible that such processes could pro- 

 duce them. In hyperplasias, however, there is nothing against 

 the assumption that the place of abnormal tissue formation is al- 

 ways the goal of an especial nutritive current; that therefore 

 an abnormally abundant su pply inp^>-Qf nutritive substanc es always 

 precedes the process of abnormal cell-division*^ . Therefore the 

 sap currents, lying at the base of hyperplastic processes, can 

 correspond ver-y well to the currents in the normally developing 

 plant so far as their direction and strength is concerned. If, 

 (133) for example, the vessels are broltcn at any point of this plant 



body, it may be assumed thg.t the normal continuance of the trans- 

 fer of substances v;ill result in an accumulation of material at 

 th© place of interruption. Just as v/e have previously traced 

 metaplastic changes to such accumulations of food-stuffs (com- 

 pare p. 59), we will try in the following pages, to Bxplain hy- 

 perplastic processes alf!o by a similar over -nutrition. Prom 

 these cases those others differ but little in which as a ro»3lt 

 of the breaking of the vessels or the non-use of material, a 

 great quantity of food stuffs is brought to places, to which, 

 under normal conditions, only moderate amounts woiild have flowed. 

 Thus, by cutting back growing shoots, dormant axillary buds may 

 be forced to bJreak, indeed evon the leaves already present may be 

 stlmula.t©d to a more luxuriant growth. Sacks^^ having removed 

 all sprouting points from Cucurbita plants, caused the embryonie 

 root cells adjacent to each petiole to grow out into extensive 

 tuTjers, even as large as walnuts. In cases of the latter kind> 

 we will speak of "correlation -hyperplasia". 



In othei- cases the abnormal accumulation of material which 

 precedes hyperplastic changes In tissue may not be explained thus 

 simply by an interruption^ of the normal nutritive streams, or by 



i««.^w«,— » — — — ". — — •-- — — — •- — — '-*'*-— — — — — — — — — 



1 Cellularpathologie, 1858, p. 56 



*^ Prom a medical point of view, Cohnheim (Vorles, uh, 

 allg. Path., 1882. Bd. I, p. 703) has referred especially to the 

 connection between abnormal formation of tissue, and increase 

 in supply of food stuff* 



^ Sesamm. Abhandl., Bd, II, p. 1172. 



