102 
Nature  and  Action  of  Toxins. 
(Am.  Jour.  Pharm. 
\      March,  1903. 
Toxins  possess  some  very  distinctive  characters :  They  produce 
their  actions  in  extremely  small  doses,  being  in  this  respect  allied 
to  ferments ;  they  act,  as  a  rule,  specifically,  i.  e.y  upon  only  a  few 
structures  ;  and  they  are  destroyed  by  specific  substances  produced 
by  cells,  especially  under  the  influence  of  the  particular  toxin. 
Both  the  toxins  and  antitoxins  are  usually  either  proteid,  or  are 
so  closely  bound  to  the  proteids  that  it  has  been  impossible  to  sepa- 
rate them;  they  are,  therefore,  sometimes  called  u  toxalbumins."  It 
is  doubtful  whether  any  toxin  has  been  isolated  in  pure  form. 
Several  have,  however,  been  purified  until  they  ceased  to  give  pro- 
teid reactions.  They  still  contained  nitrogen.  Most  toxins  are  very 
sensitive  to  the  conditions  which  alter  proteids.  They  are  often 
destroyed  by  even  moderate  heat.  Many  are  also  altered  by  fer- 
ments, so  that  they  produce  little  action  when  introduced  into  the 
alimentary  canal. 
Toxins  exist  normally  in  the  cultures  (diphtheria,  tetanus)  or  in 
the  cells  (pus  organisms)  of  a  number  of  bacteria ;  in  some  animal 
fluids  (serum,  snake  venom) ;  in  some  plants  (jequirity  and  castor- 
bean),  and  in  certain  proteids  (albumoses  and  peptones).  Other 
toxins  are  produced  by  the  body  only  through  the  stimulus  of  some 
foreign  element,  as  by  the  introduction  of  cells,  proteids  or  toxins, 
of  a  foreign  species  (or  bacteria).  These  act  then  only  on  the  sub- 
stance which  gave  rise  to  their  formation.  When  a  substance  of 
this  class  is  useful  to  the  body  by  destroying  bacteria  or  their  prod- 
ucts, it  is  called  an  antitoxin.  Antitoxins,  therefore,  differ  from 
toxins  only  by  acting  on  different  structures.  Certain  bacteria  simi- 
larly produce  toxins  only  under  the  stimulus  of  the  conditions  exist- 
ing in  the  living  body.  Other  bacteria,  as  e.g.,  anthrax,  probably 
do  not  produce  toxins  at  all,  but  act  through  the  mechanical 
impediment  which  their  numerous  cells  introduce  into  the  circula- 
tion. 
The  effects  of  toxins  (including  so-called  antitoxins)  are  generally 
exerted  upon  only  one  or  a  limited  number  of  cells  or  substances. 
They  consist  in  :  Injury  cells,  as  shown  by  the  cessation  of  move- 
ment, morphological  changes,  or  death  (toxins  producing  such 
actions  being  classed  as  cytotoxins),  or  even  by  solution  of  cells 
(cytolysins),  agglutination  of  cells  (agglutinins),  precipitation  of 
substances  (precipitins),  coagulation  (coagulins),  neutralization  of 
other  toxins  (antitoxins),  or  of  ferments  (antienzymes).  These 
