I-suprachiasmatic nucleus iyindawo encane yobuchopho enesibopho sokulawula isigqi sokujikeleza komzimba womuntu—iwashi langaphakathi elilawula isigqi sebhayoloji usuku lonke. Itholakala ku-hypothalamus, le nucleus ithola ulwazi ku-retina mayelana nokukhanya kwendawo futhi, ukusuka lapho, ivumelanisa izinqubo ezihlukahlukene zomzimba, njengokulala, izinga lokushisa lomzimba, nokukhiqizwa kwamahomoni. Ukubaluleka kwawo kubalulekile ekusebenzeni kahle komzimba nokugcina impilo.
Qonda ukuthi i-nucleus ye-suprachiasmatic isebenza kanjani, enesibopho sesigqi sokujikeleza komzimba.
I- suprachiasmatic nucleus iyisakhiwo esincane esitholakala ebuchosheni bomuntu esidlala indima ebalulekile esigqini somzimba se -circadian . Le nucleus isebenza njengewashi langaphakathi langempela, elinomthwalo wokulawula izinqubo ezahlukene zomzimba usuku lonke.
I-suprachiasmatic nucleus ithola ulwazi mayelana nokukhanya okuzungezile ngamehlo futhi isebenzisa lezi zimpawu ukuvumelanisa isigqi somzimba nomjikelezo wemvelo wamahora angu-24. Uma kukhona ukuchayeka ekukhanyeni emini , i - suprachiasmatic nucleus ithumela izimpawu kwezinye izindawo zobuchopho, okubonisa ukuthi sekuyisikhathi sokuphaphama nokusebenza.
Ngakolunye uhlangothi, ebusuku , lapho ukukhanya kuncipha, i - suprachiasmatic nucleus itshela umzimba ukuthi sekuyisikhathi sokuphumula nokulala . Lo mjikelezo wokusebenza nokuphumula ubalulekile ekulawuleni izinqubo ezahlukene zomzimba, njengokukhishwa kwama -hormone kanye nokushisa komzimba.
Ngakho-ke, i-suprachiasmatic nucleus idlala indima ebalulekile ekugcineni isigqi somzimba, iqinisekisa ukuthi imisebenzi yomzimba yenzeka ngendlela ehlelekile nehambisanayo nomjikelezo wemvelo wosuku nobusuku . Kubalulekile ukunakekela inhlanzeko yokulala nokugcina imikhuba enempilo ukuqinisekisa ukusebenza kahle kwaleli washi lobuchopho langaphakathi.
Indawo yewashi lebhayoloji ebuchosheni: thola ukuthi ikusiphi isifunda.
Iwashi lebhayoloji yobuchopho litholakala kuyi-suprachiasmatic nucleus, isifunda esincane se-hypothalamus. Le nucleus inesibopho sokulawula isigqi sokujikeleza komzimba, ukulawula isigqi sokulala nokuvuka, izinga lokushisa lomzimba, ukukhiqizwa kwamahomoni, nezinye izinqubo zomzimba.
I-nucleus ye-suprachiasmatic ithola ulwazi mayelana nokukhanya okuzungezile ngamehlo futhi ithumela amasignali kuwo wonke umzimba ukuze uvumelanise imisebenzi ngokomjikelezo wobusuku bosuku. Ngakho, lisebenza “njengewashi langaphakathi” lobuchopho, ligcina umzimba wethu uhambisana nendawo yangaphandle.
Lapho i-nucleus ye-suprachiasmatic ingasebenzi kahle, ukuphazamiseka kokulala, izinkinga zemizwa, nezinye izindaba zezempilo zingenzeka. Ngakho-ke, kubalulekile ukugcina impilo yale nucleus encane ukuze kuqinisekiswe ukusebenza kahle kwewashi lezinto eziphilayo futhi, ngenxa yalokho, nomzimba uwonke.
Iqhaza le-nucleus ye-suprachiasmatic ekulawuleni isigqi se-circadian ngokuqina okuhlukile kokukhanya.
I-suprachiasmatic nucleus (SCN) iyisifunda sobuchopho esinesibopho sokulawula isigqi sokujikeleza, noma imijikelezo yebhayoloji ethatha cishe amahora angama-24. Lezi zigqi zithonya imisebenzi eminingi yomzimba, njengokulala, izinga lokushisa lomzimba, nokukhiqizwa kwamahomoni.
Omunye wemisebenzi eyinhloko ye-SCN ukuvumelanisa lezi zigqi nomjikelezo wokukhanya nobumnyama bendawo. Ithola ulwazi mayelana nokuqina kokukhanya ngamehlo futhi ilawula ukukhiqizwa kwe-melatonin, i-hormone yokulala. Ezimweni zokukhanya okukhulu , i-SCN icindezela ukukhiqizwa kwe-melatonin, igcina umzimba usesimweni sokuphaphama.
Ngakolunye uhlangothi, ezindaweni ezinokukhanya okuphansi , i-SCN ivuselela ukukhiqizwa kwe-melatonin, ilungiselela umzimba ukuphumula. Lokhu kuchaza ukuthi kungani ukuchayeka ekukhanyeni okukhanyayo ebusuku kungaphazamisa ubuthongo kanye nesigqi se-circadian, okubangela izinkinga ezifana nokungalali kanye nokulala emini.
Ikhono layo lokuphendula amandla ahlukene okukhanya lisiza ukugcina ibhalansi phakathi komsebenzi nokuphumula, okunomthelela empilweni nasenhlalakahleni.
Yini enesibopho sokulawula isigqi se-circadian somzimba womuntu?
I- suprachiasmatic nucleus , etholakala ebuchosheni, inesibopho sokulawula isigqi se-circadian somzimba womuntu . Leli qembu elincane lamaseli ezinzwa lisebenza njengewashi langaphakathi lomzimba, lilawula amaphethini okulala nokuvuka, kanye nokuthonya ezinye izinqubo zomzimba ezilandela umjikelezo wamahora angaba ngu-24.
I-suprachiasmatic nucleus ithola ulwazi mayelana nokukhanya okuzungezile ngama -photoreceptors ku-retina, athumela izimpawu ze-neural kulesi sikhungo sokulawula. Ngale ndlela, iwashi langaphakathi liyakwazi ukuvumelana nomjikelezo wemvelo wokukhanya nobumnyama, lilungise isigqi se-circadian ngokwezimo zangaphandle.
Uma i-suprachiasmatic nucleus ingasebenzi kahle, njengasezimweni zokungalali kahle noma ukuphazamiseka kokulala, izinkinga ekusebenzeni komzimba zingavela. Ngakho-ke, kubalulekile ukugcina imikhuba enempilo nokuhlonipha izilinganiso zemvelo zomzimba ukuqinisekisa ukulala okuhle kanye nokusebenza kahle komzimba.
I-nucleus ye-Suprachiasmatic: iwashi langaphakathi lobuchopho
Nakuba sivame ukucabanga ukuthi ubuchopho bomuntu ngokuyinhloko buyisitho esisivumela ukuba sicabange futhi siqaphele izinto, iqiniso liwukuthi futhi zenza zonke izinhlobo zemisebenzi ezenzakalelayo futhi engazi lutho. Akusona nje isisekelo sebhayoloji sobuhlakani bomuntu; iphinde isingathe inqwaba yezinqubo ezibalulekile ekusindeni kwethu.
I-suprachiasmatic nucleus iyisibonelo salokhu . Nakuba izindawo ezithile ze-brainstem zinesibopho sokusebenzisa ukushaya kwenhliziyo noma ukulawula izinga lokushisa lomzimba ukuze amangqamuzana ethu angafi, lesi sakhiwo sobuchopho sisebenza njengewashi lethu langaphakathi. Okulandelayo, sizobona ukuthi lokho kusho ukuthini kanye nokuthi yiziphi izici zomzimba ezivezwa yi-suprachiasmatic nucleus.
Iyini i-nucleus ye-suprachiasmatic?
Siyaqonda ukuthi i-suprachiasmatic nucleus iyisakhiwo esincane esakhiwe cishe ama-neurons angu-20.000 atholakala endaweni ye-hypothalamus eseduze nobuso, okungukuthi, engxenyeni engezansi ye-diencephalon. Yakhiwe ngombala ompunga.
Khumbula ukuthi kukhona i-suprachiasmatic nucleus kuyo yonke i-cerebral hemisphere , okusho ukuthi zimbili ngomuntu ngamunye ohlangothini ngalunye lwekhanda.
Indawo yakho
Njengoba igama lisho, i-suprachiasmatic nucleus itholakala ngaphezu kwe-optic chiasm , okuyindawo etholakala phansi kobuchopho lapho imizwa ye-optic iwela khona, idlulela kolunye uhlangothi lomzimba. Kungenzeka futhi ukuyithola kusetshenziswa i-hypothalamus njengereferensi, njengoba itholakala engxenyeni engaphambili yalesi sakhiwo sobuchopho, igudla izinhlangothi zombili ze-ventricle yesithathu yobuchopho.
Iqiniso lokuthi i-optic chiasm itholakala ngenhla nje kwemizwa ye-optic ayiyona ingozi; empeleni, ukusebenza kwayo kuhlobene nezimpawu zokukhanya ezithathwe i-retina, njengoba sizobona.
Imisebenzi ye-nucleus ye-suprachiasmatic
Umsebenzi oyinhloko we-suprachiasmatic nucleus ukulawula imigqi ye-circadian elawula amazinga omsebenzi womzimba, kuye ngesikhathi esikuso. Imigqi ye-circadian imijikelezo enquma ukuthi kunesidingo esikhulu sokuphumula nini nokuthi kunini lapho kunamandla amaningi atholakalayo, ngakho-ke sizohamba kakhulu, sicabange kangcono, njll.
Ngamanye amazwi, i-nucleus ye-suprachiasmatic ingenelela emijikelezweni yokulala futhi yandisa amathuba okulala ngezikhathi ezithile nokuvuka kwabanye, isibonelo, nokungabi namandla afanayo ngehora le-12 njengasemva kwesidlo sakusihlwa.
Imijikelezo elawula i-suprachiasmatic nucleus ihlala amahora angama-24, njengoba ukuziphendukela kwemvelo kuye kwabangela ukuba ivumelane nobude bosuku lwemvelo ngokusekelwe enanini lokukhanya elibanjwe amehlo ethu.
Ngakho-ke, uma sibhekene nokukhanya, lokhu kuchazwa yilesi sakhiwo sobuchopho njengobufakazi bokuthi sekuyisikhathi sokuhlala siphapheme isikhathi eside, futhi ukukhiqizwa okukhulu kwe-melatonin , i-hormone eningi kakhulu ngaphambi nje, kuyabambezeleka ukuze siqale ukulala futhi ngenkathi sisalokhu sisesigabeni sokulala.
Indlela yokusebenza
Lapho sibheka ndawana thize, ukukhanya okubonisa lokho esikubukayo kuphumela kuyi-retina, ungqimba lwamangqamuzana angaphakathi kweso futhi abanye ososayensi abayibheka njengengxenye ye-diencephalon.
Lolu lwelwesi luqoqa izimpawu zikagesi lapho kuhunyushwa khona amaphethini okukhanya kwalokho esikubonayo bese luthumela lolu lwazi ebuchosheni ngemizwa yokubona. Indlela evamile yolwazi oluningi idlula ku-thalamus kanye ne-occipital lobe, indawo lapho ulwazi olubonakalayo luqala ukuhlanganiswa khona kumayunithi amakhulu futhi aphelele.
Nokho, okunye kwalokhu kwaziswa kuyachezuka kulo mzila ku-optic chiasm, etholakala “esangweni” lobuchopho ukuze kufinyelele kuyi-nucleus ye-suprachiasmatic. Lesi sakhiwo asiyiboni imininingwane yamaphethini, umumo, noma ukunyakaza kokukhanya, kodwa siyazwela kulo lonke inani lokukhanya eliqoqwa ama-retina. Lokhu kubangela ukuthi imiyalo ithunyelwe kwezinye izindawo zomzimba ezihlobene nezigqi ze-circadian, njenge-pituitary gland eseduze.
Ngale ndlela, imizimba yethu ivumelana nalokho ekuhumusha njengezidingo zemvelo. Phela, uma siklanyelwe ukusebenza kahle kakhulu phakathi nosuku, kungcono ukusebenzisa lezi zikhathi futhi sivumele amahora obumnyama aphumule, ngokuya ngomqondo wokukhetha kwemvelo.
Kodwa-ke, ukusetshenziswa kwemithombo yokukhanya yokwenziwa kungaba nemiphumela emibi, futhi, isibonelo, ukuziveza ekukhanyeni okuvela esikrinini sekhompyutha ngaphambi nje kokulala kungabangela ukuqwasha, noma ngabe sikhathele usuku olude emsebenzini. Lokhu kwenza umzimba wethu uzame ukusabela esimweni esingajwayelekile owawungasilungiselelanga: izinsuku ezinamahora amaningi okukhanya.