the origin and nature of emotions-第31章

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inst　changes　in　the　Nissl　substance　morphingave　a　negative　result　in　the　Cannon　test　for　adrenalin。　After　excision　of　the　adrenals；　or　after　division　of　their　nerve　supply；　all　Cannon　tests　for　adrenalin　were　negative。

Histologic　Study　of　the　Adrenals。Histologic　studies　of　the　adrenals　after　the　application　of　the　adequate　stimuli　which　gave　positive　results　to　the　Cannon　test　for　adrenalin　are　now　in　progress；　and　thus　far　the　histologic　studies　corroborate　the　functional　tests。

In　hibernating　woodchucks；　the　cells　of　the　adrenal　cortex　were　found　to　be　vacuolated　and　shrunken。　　In　one　hundred　hours　of　insomnia；　in　surgical　shock；　in　strong　fear；　in　exhaustion　from　fighting；　after　peptone　injections；　in　acute　infections；　the　adrenals　undergo　histologic　changes　characteristic　of　exhaustion　（Figs。　66　to　67）。

We　have　shown　that　brain　and　adrenal　activity　go　hand　in　hand；　that　is；　that　the　adrenal　secretion　activates　the　brain；　and　that　the　brain　activates　the　adrenals。　　The　fundamental　question　which　now　arises　is　this：　　Are　the　brain　and　the　adrenals　interdependent？　A　positive　answer　may　be　given　to　this　question；　for　the　evidence　of　the　dependence　of　the　brain　upon　the　adrenals　is　as　clear　as　is　the　evidence　of　the　dependence　of　the　adrenals　upon　the　brain。　（1）　After　excision　of　the　adrenals；　the　brain…cells　undergo　continuous　histologic　and　functional　deterioration　until　death。　During　this　time　the　brain　progressively　loses　its　power　to　respond　to　stimuli　and　there　is　also　a　progressive　loss　of　muscular　power　and　a　diminution　of　body　temperature。　（2）　｛illust。　caption　=　FIG。　　66。In　our　crossed　circulation　experiments　we　found　that　adrenalin　alone　could　cause　increased　brain　activity；　while　histologically　we　know　that　adrenalin　alone　causes　an　increase　of　the　Nissl　substance。　　An　animal；　both　of　whose　adrenals　had　been　excised；　showed　no　hyperchromatism　in　the　brain…cells　after　the　injection　of　strychnin；　toxins；　foreign　proteins；　etc。　（3）　When　the　adrenal　nerve　supply　is　divided　（Cannon…Elliott）；　then　there　is　no　increased　adrenal　activity　in　response　to　adequate　stimuli。

From　these　studies　we　are　forced　to　conclude　not　only　that　the　brain　and　adrenals　are　interdependent；　but　that　the　brain　is　actually　more　dependent　upon　the　adrenals　than　the　adrenals　upon　the　brain；　since　the　brain　deteriorates　progressively　to　death　without　the　adrenals；　while　the　adrenal　whose　connection　with　the　brain　has　been　broken　by　the　division　of　its　nerve　supply　will　still　produce　sufficient　adrenalin　to　support　life。

From　the　strong　affinity　of　the　brain…cells　for　adrenalin　which　was　manifested　in　our　experiments　we　may　strongly　suspect　that　the　Nissl　substance　is　a　volatile；　extremely　unstable　combination　of　certain　elements　of　the　brain…cells　and　adrenalin；　because　the　adrenals　alone　do　not　take　the　Nissl　stain　and　the　brain　deprived　of　adrenalin　also　does　not　take　Nissl　stain。　　The　consumption　of　the　Nissl　substance　in　the　brain…cells　is　lessened　or　prevented　by　morphin；　as　is　the　output　of　adrenalin；　and　the　consumption　of　the　Nissl　substance　is　also　lessened　or　prevented　by　nitrous　oxid。　But　morphin　does　not　prevent　the　action　of　adrenalin　injected　into　the　circulation；　hence　the　control　of　morphin　over　energy　expenditure　is　exerted　directly　on　the　brain…cells。　Apparently　morphin　and　nitrous　oxid　both　act　through　this　interference　with　oxidation　in　the　brain。　　We；　therefore；　conclude　that　within　a　certain　range　of　acidity　of　the　blood　adrenalin　can　unite　with　the　brain…cells　only　through　the　mediation　of　oxygen；　and　that　the　combination　of　adrenalin；　oxygen；　and　certain　brain…cell　constituents　causes　the　electric　discharge　that　produces　heat　and　motion。　In　this　interrelation　of　the　brain　and　the　adrenals　we　have　what　is；　perhaps；　the　master　key　to　the　automatic　action　of　the　body。　Through　the　special　senses　environmental　stimuli　reach　the　brain　and　cause　it　to　liberate　energy；　which　in　turn　activates　certain　other　organs　and　tissues；　among　which　are　the　adrenals。　　The　increased　output　of　adrenalin　activates　the　brain　to　still　greater　activity；　as　a　result　of　which　again　the　entire　sympathetic　nervous　system　is　further　activated；　as　is　manifested　by　increased　heart　action；　more　rapid　respiration；　raised　blood…pressure；　increased　output　of　glycogen；　increased　power　of　the　muscles　to　metabolize　glucose；　etc。

If　this　conclusion　be　well　founded；　we　should　find　corroborative　evidence　in　histologic　changes　in　that　great　storehouse　of　potential　energy；　the　liver；　as　a　result　of　the　application　of　each　of　the　adequate　stimuli　which　produced　brain…cell　and　adrenal　changes。


The　Liver

Prolonged　insomnia；　prolonged　physical　exertion；　infections；　injections　of　toxins　and　of　strychnin；　rage　and　fear；　physical　injury　under　anesthesia；　in　fact；　all　the　adequate　stimuli　which　affected　the　brain　and　the　adrenals；　produced　constant　and　identical　histologic　changes　in　the　liverthe　cells　stained　poorly；　the　cytoplasm　was　vacuolated；　the　nuclei　were　crenated；　the　cell　membranes　were　irregular；　the　most　marked　changes　occurring　in　the　cells　of　the　periphery　of　the　lobules　（Figs。　69　and　70）。　In　prolonged　insomnia　the　striking　changes　in　the　liver　were　repaired　by　one　seance　of　sleep。

Are　the　histologic　changes　in　the　liver　cells　due　to　metabolism　or　toxic　products；　or　are　they　〃work〃　changes　incident　to　the　conversion　of　latent　into　kinetic　energy？　　Are　the　brain；　adrenals；　and　liver　interdependent？　The　following　facts　establish　the　answers　to　these　queries：

（1）　The　duration　of　life　after　excision　of　the　liver　is　about　the　same　as　after　adrenalectomyapproximately　eighteen　hours。

（2）　The　amount　of　glycogen　in　the　liver　was　diminished　in　all　the　experiments　showing　brain…adrenal　activity；　and　when　the　histologic　changes　were　repaired；　the　normal　amount　of　glycogen　was　again　found。

（3）　In　crossed　circulation　experiments　changes　were　found　in　the　liver　of　the　animal　whose　brain　received　the　stimulus。

From　these　premises　we　must　consider　that　the　brain；　the　adrenals；　and　the　liver　are　mutually　dependent　on　one　another　for　the　conversion　of　latent　into　kinetic　energy。　　Each　is　a　vital　organ；　each　equally　vital。　It　may　be　said　that　excision　of　the　brain　may　apparently　cause　death　in　less　time　than　excision　of　the　liver　or　adrenals；　but　this　statement　must　be　modified　by　our　definition　of　death。　　If　all　the　brain　of　an　animal　be　removed　by　decapitation；　its　body　may　live　on　for　at　least　eleven　hours　if　its　circulation　be　maintained　by　transfusion。　An　animal　may　live　for　weeks　or　months　after　excision　of　the　cerebral　hemispheres　and　the　cerebellum；　while　an　overtransfused　animal　may　live　many　hours；　days　even；　after　the　destruction　of　the　medulla。　It　is　possible　even　that　the　brain　actually　is　a　less　vital　organ　than　either　the　adrenals　or　the　liver。

In　our　research　to　discover　whether　any　other　organs　should　be　included　with　the　brain；　the　adrenals；　and　the　liver　in　this　mutually　interdependent　relation；　we　hit　upon　an　experiment　which　throws　light　upon　this　problem。

Groups　of　rabbits　were　gently　kept　awake　for　one　hundred　hours　by　relays　of　students；　an　experiment　which　steadily　withdrew　energy　but　caused　not　the　slightest　physical　or　emotional　injury　to　any　of　them；　no　drug；　toxin；　or　other　agent　was　given　to　them；　they　were　given　sufficient　food　and　drink。　　In　brief；　the　internal　and　external　environments　of　these　animals　were　kept　otherwise　normal　excepting　for　the　gentle　stimuli　which　insured　continued　wakefulness。　This　protracted　insomnia　gradually　exhausted　the　animals　completely；　some　to　the　point　of　death　even。　　Some　of　the　survivors　were　killed　immediately　after　the　expiration　of　one　hundred　hours　of　wakefulness；　others　after　varying　intervals。

Histologic　studies　were　made　of　every　tissue　and　organ　in　the　body。　Three　organs；　the　brain；　the　adrenals；　and　the　liver；　and　these　three　only；　showed　histologic　changes。　　In　these　three　organs　the　histologic　changes　were　marked；　and　were　almost　wholly　repaired　by　one　seance　of　sleep。　In　each　instance　these　histologic　changes　were　identical　with　those　seen　after　physical　exertion；　emotions；　toxins；　etc。＇*＇　It　would　appear；　then；　that　these　three　organs　take　the　stress　of　life　the　bra