çäœé»æ°ã®é åçãªäžçãæ¢æ±ãåºæ¬åçã现èã¡ã«ããºã ãããå»åŠãçåœå·¥åŠãªã©ãžã®å¿çšãŸã§ã解説ããå æ¬çã¬ã€ãã
çäœé»æ°ã®ç§åŠïŒçåœã®é»æ°çèšèªãè§£ãæãã
çäœé»æ°ãããªãã¡çäœå ã§çºçãã黿°çŸè±¡ã¯ãçåœãã®ãã®ã®æ ¹æºçãªåŽé¢ã§ããè³å ã®ãã¥ãŒãã³ã®çºç«ããå¿èã®å調çãªåçž®ã«è³ããŸã§ãçäœé»æ°ä¿¡å·ã¯å€çš®å€æ§ãªçç©åŠçããã»ã¹ãçµ±å¶ããŠããŸãããã®å æ¬çãªã¬ã€ãã§ã¯ãçäœé»æ°ã®ç§åŠãæ¢æ±ãããã®åºæ¬åçã倿§ãªå¿çšããããŠãã®é åçãªåéãžã®çè§£ãåºãç¶ããæå 端ã®ç ç©¶ã«ã€ããŠæ·±ãæãäžããŸãã
çäœé»æ°ãšã¯ïŒ
ãã®æ žå¿ã«ãããŠãçäœé»æ°ã¯ã€ãªã³ïŒé»è·ã垯ã³ãååãååïŒã现èèãæšªåãåãããçããŸãããããã®ã€ãªã³ãäŸãã°ãããªãŠã ïŒNa+ïŒãã«ãªãŠã ïŒK+ïŒãã«ã«ã·ãŠã ïŒCa2+ïŒãå¡©åç©ïŒCl-ïŒã¯ãæ§ã ãªçŽ°èæ©èœãé§åãã黿°çåŸé ãäœãåºããŸãããããã®ã€ãªã³ã®äžåäžãªååžã¯ã现èèãæšªåãé»å§å·®ãããªãã¡èé»äœãšããŠç¥ããããã®ãçã¿åºããŸãããã®é»äœå·®ãçäœé»æ°ä¿¡å·ã®åºç€ãšãªããŸãã
ããããªãŒãæ³åããŠã¿ãŠãã ãããããã«ã¯ãã©ã¹ãšãã€ãã¹ã®ç«¯åããããŸããåæ§ã«ã现èãå å€ã§ã€ãªã³æ¿åºŠãç°ãªããé»äœãçã¿åºããŠããŸãããã®é»è·ã®å·®ã«ãã£ãŠã现èã¯äºãã«éä¿¡ããç¹å®ã®ã¿ã¹ã¯ãå®è¡ããããšãã§ããã®ã§ãã
çäœé»æ°ã®åºæ¬åç
ã€ãªã³é»æµãšèé»äœ
现èèãæšªåãã€ãªã³ã®åãã¯ã€ãªã³é»æµãçæããŸãããããã®é»æµã¯ã€ãªã³ãã£ãã«ãšåŒã°ããç¹æ®ãªã¿ã³ãã¯è³ªãã£ãã«ã«ãã£ãŠèª¿ç¯ãããŠãããç¹å®ã®ã€ãªã³ãéžæçã«èãééãããŸããã€ãªã³ãã£ãã«ã«ã¯æ§ã ãªçš®é¡ãããããããããç¬èªã®ç¹æ§ãšéžææ§ãæã£ãŠããŸããåžžã«éããŠãããã£ãã«ãããã°ãèé»äœã®å€åïŒé»äœäŸåæ§ãã£ãã«ïŒããªã¬ã³ãã®çµåïŒãªã¬ã³ãäŸåæ§ãã£ãã«ïŒããŸãã¯æ©æ¢°çã¹ãã¬ã¹ïŒæ©æ¢°å容ãã£ãã«ïŒãªã©ã®ç¹å®ã®åºæ¿ã«å¿ããŠééããã²ãŒãä»ãã®ãã£ãã«ããããŸãã
ãã«ã³ã¹ãã®åŒã¯ãã€ãªã³ã®å¹³è¡¡é»äœãçè§£ããããã®çè«çæ çµã¿ãæäŸããŸãã平衡é»äœãšã¯ããã®ã€ãªã³ã®èãæšªåãæ£å³ã®ç§»åããŒãã«ãªãèé»äœã®ããšã§ãããŽãŒã«ããã³ã»ããžãã³ã»ã«ããïŒGHKïŒã®åŒã¯ããã®æŠå¿µãæ¡åŒµããè€æ°ã®ã€ãªã³ãå šäœã®èé»äœã«äžããå¯äžãèæ ®ããŸãã
掻åé»äœïŒãã¥ãŒãã³ã®èšèª
çäœé»æ°ã®æãããç¥ãããäŸã®äžã€ã掻åé»äœã§ããããã¯ããã¥ãŒãã³ãç现èãªã©ã®è奮æ§çްèã§çºçãããèé»äœã®æ¥éãã€äžéæ§ã®å€åã§ããæŽ»åé»äœã¯ããã¥ãŒãã³ãé·è·é¢ã«ããã£ãŠæ å ±ãäŒéããããã®äž»èŠãªææ®µã§ãããã®ããã»ã¹ã¯ãæ éã«èª¿æŽãããäžé£ã®ã¹ãããã§å±éãããŸãïŒ
- 鿢é»äœïŒãã¥ãŒãã³ã¯è² ã®éæ¢èé»äœïŒéåžžã¯çŽ-70 mVïŒãç¶æããŠããŸãã
- è±å極ïŒåºæ¿ã«ãã£ãŠèé»äœãããæ£ã®æ¹åã«å€åããŸãã
- éŸå€ïŒè±å極ãããéŸå€ïŒéåžžã¯çŽ-55 mVïŒã«éãããšãé»äœäŸåæ§ãããªãŠã ãã£ãã«ãéããŸãã
- äžæçžïŒãããªãŠã ã€ãªã³ã现èå ã«æµå ¥ããæ¥éãªè±å極ãšèé»äœã®æ¥æ¿ãªäžæãåŒãèµ·ãããŸãã
- å忥µïŒé»äœäŸåæ§ãããªãŠã ãã£ãã«ãäžæŽ»æ§åããé»äœäŸåæ§ã«ãªãŠã ãã£ãã«ãéããŸããã«ãªãŠã ã€ãªã³ã现èå€ã«æµåºããè² ã®èé»äœãå埩ããŸãã
- é忥µïŒèé»äœãäžæçã«éæ¢é»äœãããè² ã«ãªããŸãã
- 鿢é»äœãžã®åŸ©åž°ïŒãããªãŠã -ã«ãªãŠã ãã³ãïŒNa+/K+ ATPaseïŒãªã©ã®ã€ãªã³ãã³ãããèãæšªåã£ãŠã€ãªã³ãèœå茞éãã鿢æã®ã€ãªã³æ¿åºŠãå埩ãããŸãã
掻åé»äœã¯ãã¥ãŒãã³ã®è»žçŽ¢ã«æ²¿ã£ãŠäŒæããä»ã®ãã¥ãŒãã³ãæšç现èã«ä¿¡å·ãäŒéããããšãå¯èœã«ããŸãã軞玢ãçµ¶çžããèèªç©è³ªã§ããããšãªã³ã¯ãè·³èºäŒå°ãšåŒã°ããããã»ã¹ãéããŠæŽ»åé»äœã®äŒæé床ãå¢å ãããŸãããã®ããã»ã¹ã§ã¯ã掻åé»äœã¯ããšãªã³éã®ééïŒã©ã³ãŽã£ãšã®çµèŒªïŒãããžã£ã³ããããŸãã
现èéã³ãã¥ãã±ãŒã·ã§ã³ïŒã®ã£ããçµå
现èã¯ãŸããã®ã£ããçµåãšåŒã°ããç¹æ®ãªãã£ãã«ãä»ããŠäºãã«çŽæ¥ã³ãã¥ãã±ãŒã·ã§ã³ããšããŸãããããã®ãã£ãã«ã¯ã€ãªã³ãå°ååããã现èããå¥ã®çްèãžçŽæ¥ééããã飿¥ãã现èéã®é»æ°çããã³ä»£è¬ççµåãä¿é²ããŸããã®ã£ããçµåã¯ãçµç¹ãåšå®ãç¹ã«å¿èãå¹³æ»çã«ãããçŽ°èæŽ»åã®å調ã«éèŠãªåœ¹å²ãæãããŸãã
çäœé»æ°ã®å¿çš
çäœé»æ°ã®çè§£ã¯ãå»åŠãçåœå·¥åŠããã®ä»ã®åéã§æ°å€ãã®å¿çšã«ã€ãªãã£ãŠããŸãã
å»åŠ
ç¥çµç§åŠãšç¥çµåŠ
çäœé»æ°ã¯ãç¥çµç³»ã®ç ç©¶ã§ããç¥çµç§åŠã«ãããŠäžå¿çãªåœ¹å²ãæãããŸããè³æ³¢èšïŒEEGïŒãçé»å³ïŒEMGïŒãªã©ã®æè¡ã¯ãããããè³ãçèã®é»æ°æŽ»åãæž¬å®ããããã«äœ¿çšãããŸããEEGã¯ãŠããããç¡ç é害ãªã©ã®ç¶æ ã蚺æããããã«äœ¿çšãããEMGã¯çæ©èœã®è©äŸ¡ãç¥çµççŸæ£ã®èšºæã«äœ¿çšãããŸãã
äŸãã°ãç ç©¶è ãã¡ã¯EEGã䜿çšããŠã麻çºã®ãã人ã ãæèã«ãã£ãŠå€éšããã€ã¹ãå¶åŸ¡ã§ãããã¬ã€ã³ã»ã³ã³ãã¥ãŒã¿ãŒã»ã€ã³ã¿ãŒãã§ãŒã¹ïŒBCIïŒãéçºããŠããŸãã
å¿è黿°ççåŠ
å¿è黿°ççåŠã¯ãå¿èã®é»æ°æŽ»åã«çŠç¹ãåœãŠãŠããŸããå¿é»å³ïŒECGïŒã¯ãå¿èã®é»æ°æŽ»åãæž¬å®ããäžæŽèïŒäžèŠåãªå¿æïŒãªã©ã®å¿èã®ç¶æ ã蚺æããããã«äœ¿çšãããé䟵襲çãªæè¡ã§ããããŒã¹ã¡ãŒã«ãŒãæ€èŸŒã¿åé€çްååšïŒICDïŒã¯ã黿°åºæ¿ãçšããŠå¿ãªãºã ã調ç¯ããçªç¶ã®å¿èæ»ãé²ãããã®ããã€ã¹ã§ãã
å¿å®€çްåã«ãã£ãŠåŒãèµ·ããããããšãå€ãå¿èçªç¶æ»ã¯ãäžççãªäž»èŠãªå¥åº·åé¡ã§ããICDã¯ããããã®çåœãè ããç¶æ³ã§æ£åžžãªå¿ãªãºã ãå埩ãããããã«é»æ°ã·ã§ãã¯ãäžããŸããããå°åã§æŽç·ŽãããICDã®éçºã¯ããªã¹ã¯ã®ããå人ã®çåçãå€§å¹ ã«åäžãããŸããã
ãã€ãªãšã¬ã¯ããããã¯å»ç
ãã€ãªãšã¬ã¯ããããã¯å»çã¯ãç¥çµç³»ã®é»æ°æŽ»åã調ç¯ããããšã«ãã£ãŠçŸæ£ãæ²»çããããšãç®æãæ°èåéã§ãããã®ã¢ãããŒãã«ã¯ãæ€èŸŒã¿åããã€ã¹ã䜿çšããŠç¹å®ã®ç¥çµãåºæ¿ããããã«ãã£ãŠæšçãšãªãèåšãçµç¹ã®æ©èœã«åœ±é¿ãäžããããšãå«ãŸããŸãããã€ãªãšã¬ã¯ããããã¯å»çã¯ãççæ§çŸæ£ãèªå·±å ç«çŸæ£ãä»£è¬æ§çŸæ£ãªã©ãåºç¯ãªç¶æ ã®æ²»çã«æåŸ ãå¯ããããŠããŸãã
äŸãã°ãè¿·èµ°ç¥çµåºæ¿ïŒVNSïŒã¯ããŠãããããã€ç ãççæ§è žçŸæ£ã®æ²»çæ³ãšããŠç ç©¶ãããŠããŸããç ç©¶è ãã¡ã¯ãŸããç³å°¿ç æ£è ã®è¡ç³å€ãå¶åŸ¡ããããèªå·±å ç«çŸæ£æ£è ã®å ç«æ©èœãæ¹åãããããããã«ããã€ãªãšã¬ã¯ããããã¯ããã€ã¹ã®äœ¿çšã暡玢ããŠããŸãã
åçå»ç
æ°ããªç ç©¶ã¯ãçäœé»æ°ä¿¡å·ãçµç¹åçã«ãããŠéèŠãªåœ¹å²ãæããããšã瀺åããŠããŸããç ç©¶ã«ãããšãæå·ããçµç¹ã«é»å Žãå°å ããããšã§ãåµå·æ²»çã骚åçãããã«ã¯äžéšã®çš®ã§ã¯åè¢ã®åçãä¿é²ã§ããããšã瀺ãããŠããŸãããã®åéã¯ãŸã åææ®µéã«ãããŸãããæå·ããçµç¹ãèåšã修埩ããããã®æ°ããæ²»çæ³ãéçºãã倧ããªå¯èœæ§ãç§ããŠããŸãã
äŸãã°ãé©ç°çãªåçèœåãæã€ãµã³ã·ã§ãŠãŠãªã«é¢ããç ç©¶ã§ã¯ã黿°ä¿¡å·ã倱ãããåè¢ã®åçãèªå°ããããšãæããã«ãããŠããŸããç§åŠè ãã¡ã¯ããã®ããã»ã¹ã«é¢äžããç¹å®ã®ã€ãªã³é»æµãšã·ã°ãã«äŒéçµè·¯ã調æ»ããŠããããããã®çºèŠãããã®åçå»çã«å¿çšããããšãç®æããŠããŸãã
çåœå·¥åŠ
ãã€ãªã»ã³ãµãŒ
çäœé»æ°ã¯ãçäœååãããã»ã¹ãæ€åºã»æž¬å®ããããã€ã¹ã§ãããã€ãªã»ã³ãµãŒã®éçºã«å©çšãããŠããŸããäŸãã°ã黿°ååŠãã€ãªã»ã³ãµãŒã¯ãç¹å®ã®åæç©ïŒäŸïŒã°ã«ã³ãŒã¹ãDNAïŒã®ååšã«å¿çããŠçãã黿µãé»å§ã®å€åãæž¬å®ããããã«é»æ¥µã䜿çšããŸãããããã®ã»ã³ãµãŒã¯ãå»ç蚺æãç°å¢ã¢ãã¿ãªã³ã°ãé£åå®å šã«å¿çšãããŠããŸãã
äžçäžã®äœçŸäžäººãã®ç³å°¿ç æ£è ã䜿çšããŠããæºåž¯åè¡ç³æž¬å®åšã¯ã黿°ååŠãã€ãªã»ã³ãµãŒã®ä»£è¡šçãªäŸã§ãããããã®ããã€ã¹ã¯ãå°éã®è¡æ¶²ãµã³ãã«ãšé µçŽ ä¿®é£Ÿé»æ¥µã䜿çšããŠãè¡ç³å€ãè¿ éãã€æ£ç¢ºã«æž¬å®ããŸãã
ãã¥ãŒã©ã«ã€ã³ã¿ãŒãã§ãŒã¹
ãã¥ãŒã©ã«ã€ã³ã¿ãŒãã§ãŒã¹ã¯ãç¥çµç³»ãã³ã³ãã¥ãŒã¿ãŒã矩è¢ãªã©ã®å€éšããã€ã¹ã«æ¥ç¶ããããã€ã¹ã§ãããããã®ã€ã³ã¿ãŒãã§ãŒã¹ã¯ãè³ãšããã€ã¹ã®éã§æ å ±ãäŒéããããã«çäœé»æ°ä¿¡å·ã«äŸåããŠããŸãããã¥ãŒã©ã«ã€ã³ã¿ãŒãã§ãŒã¹ã¯ã麻çºããå人ã®éåæ©èœãå埩ãããç¥çµçŸæ£ãæ²»çãã人éã®èœåãåäžãããããã«éçºãããŠããŸãã
ãã¥ãŒã©ã«ã€ã³ã¿ãŒãã§ãŒã¹ã®äžçš®ã§ããè³æ·±éšåºæ¿çæ³ïŒDBSïŒã¯ãããŒãã³ãœã³ç ãæ¬æ æ§æ¯æŠããã®ä»ã®éåéå®³ã®æ²»çã«äœ¿çšãããŸããDBSã§ã¯ãç¹å®ã®è³é åã«é»æ¥µãæ€ã蟌ã¿ã黿°åºæ¿ãäžããŠç¥çµæŽ»åã調ç¯ããŸãããã®åºæ¿ã¯ãæ¯æŠã硬çŽãåäœã®ç·©æ ¢ããªã©ã®çç¶ãç·©åããã®ã«åœ¹ç«ã¡ãŸãã
ãã©ãã°ããªããªãŒã·ã¹ãã
çäœé»æ°ã¯ãè¬ç©ééãå¶åŸ¡ããããã«å©çšã§ããŸãã黿°çã«èªçºããããã©ãã°ããªããªãŒã·ã¹ãã ã¯ã黿°åºæ¿ã䜿çšããŠãªã¶ãŒããŒããè¬ç©ãæŸåºãããã现èèã®ééæ§ãé«ããŠè¬ç©ã现èã«å®¹æã«å ¥ãããã«ãããããŸãããããã®ã·ã¹ãã ã¯ãæšçåãããå¶åŸ¡ãããè¬ç©ééã®å¯èœæ§ãæäŸããæ²»ç广ãåäžãããå¯äœçšã軜æžããããšãã§ããŸãã
ã€ãªã³ããã©ã¬ãŒã·ã¹ã¯ã黿µãçšããŠç®èãè¶ããŠè¬ç©ãé§åãããæè¡ã§ãããçã¿æ¢ããççããã®ä»ã®ç¶æ ã®è¬ç©ãééããããã«äœ¿çšãããŸãããã®æè¡ã¯æ¶ååšç³»ãè¿åããè¬ç©ãæšççµç¹ã«çŽæ¥ééããããšã§ãå šèº«æ§ã®å¯äœçšã軜æžã§ããŸãã
çŸåšã®ç ç©¶ãšä»åŸã®æ¹åæ§
çäœé»æ°ã®ç ç©¶ã¯ããã€ãããã¯ã§æ¥éã«é²åããŠããåéã§ããçŸåšã®ç ç©¶ã¯ä»¥äžã®ç¹ã«çŠç¹ãåœãŠãŠããŸãïŒ
- ããæŽç·Žããããã€ãªãšã¬ã¯ããããã¯ããã€ã¹ã®éçºïŒããã«ã¯ãç¥çµåºæ¿ããã©ãã°ããªããªãŒããã®ä»ã®å¿çšã®ããã®ãããå°åã§ãšãã«ã®ãŒå¹çãé«ããçäœé©åæ§ã®é«ãããã€ã¹ã®éçºãå«ãŸããŸãã
- äœå ã®çäœé»æ°ã©ã³ãã¹ã±ãŒãã®ãããã³ã°ïŒç ç©¶è ãã¡ã¯ãæ§ã ãªçµç¹ãåšå®ã«ããã黿°æŽ»åã®è©³çްãªããããäœæããŠãããããã«ããçäœé»æ°ãççåŠçããã»ã¹ãã©ã®ããã«èª¿ç¯ããŠãããã«ã€ããŠã®çè§£ãæ·±ãŸããŸãã
- çäœé»æ°ä¿¡å·ã®ååã¡ã«ããºã ã®è§£æïŒããã«ã¯ãçäœé»æ°çŸè±¡ã«é¢äžããç¹å®ã®éºäŒåãã¿ã³ãã¯è³ªãã·ã°ãã«äŒéçµè·¯ãç¹å®ããããšãå«ãŸããŸãã
- çºçãšèåã«ãããçäœé»æ°ã®åœ¹å²ã®æ¢æ±ïŒç ç©¶ã§ã¯ãçäœé»æ°ä¿¡å·ãèçºçãèåããã»ã¹ã«ã©ã®ããã«åœ±é¿ãããã調æ»ããŠããŸãã
- åºç€ç ç©¶ã®ææãèšåºå¿çšã«è»¢æããïŒããã«ã¯ãçäœé»æ°ã®åçã«åºã¥ããæ°ããæ²»çæ³ã蚺æããŒã«ã®éçºãå«ãŸããŸãã
å«ççèå¯
çäœé»æ°ã«åºã¥ãæè¡ã鲿©ããã«ã€ããŠãå«ççãªæå³åããèæ ®ããããšãäžå¯æ¬ ã§ããæ€èŸŒã¿åãã€ãªãšã¬ã¯ããããã¯ããã€ã¹ã®å®å šæ§ãé·æçãªåœ±é¿ããã¥ãŒã©ã«ã€ã³ã¿ãŒãã§ãŒã¹ã®æªçšã®å¯èœæ§ãçäœé»æ°ããŒã¿ã®ãã©ã€ãã·ãŒã«é¢ããæžå¿µãçããŸãããããã®å«çç課é¡ã«å¯ŸåŠããçäœé»æ°æè¡ã責任ãæã£ãŠããã¹ãŠã®äººã®å©çã®ããã«äœ¿çšãããããšãä¿èšŒããããã«ã¯ããªãŒãã³ã§éææ§ã®ããè°è«ãå¿ èŠã§ãã
çµè«
çäœé»æ°ã¯çåœã®æ ¹æºçãªåŽé¢ã§ãããå€å²ã«ãããçç©åŠçããã»ã¹ãé§åããŠããŸãããã¥ãŒãã³ã®çºç«ããå¿èã®å調çãªåçž®ãŸã§ãçäœé»æ°ä¿¡å·ã¯çåœã®è€éãªäº€é¿æ²ãææ®ããŠããŸããçäœé»æ°ã®çè§£ã¯ãå»åŠãçåœå·¥åŠããã®ä»ã®åéã§æ°å€ãã®å¿çšããããããçŸæ£ã®æ²»çãæ©èœã®å埩ããããŠäººéã®èœåã®åäžãšãã£ãå¯èœæ§ãæäŸããŠããŸããçäœé»æ°ã®ç ç©¶ãé²ã¿ç¶ããã«ã€ããŠãããã¯å»åŠã«é©åœããããããäžçèŠæš¡ã§ãã«ã¹ã±ã¢ã®æªæ¥ã圢äœãæ å¢ã«ãããŸããç§ãã¡ã®äžã«ãããã®è€éãªã黿°çèšèªããããã«æ¢æ±ããããšã¯ãç°ãªã瀟äŒãæåãè¶ããŠäººã ã®ç掻ãåäžããããšããåžæãç§ããŠããŸãã