I-Brain Res. 2006 Dec 18; 1126 (1): 56-65. I-Epub 2006 Sep 15.
Umthombo
UMnyango Wezezimo Zengqondo, i-Purdue University, i-703 Street Street, West Lafayette, IN 47907, eU.SA. [i-imeyili ivikelwe]
abstract
I-neurobiology yezenzo zokuziphatha ngokocansi iye igxile kakhulu ekusebenzeni kwe-hormone action on cell cells futhi ukuthi lezi zimphumela zihumusha kanjani ekuboniseni amaphethini emoto yokukopisha. Ngokubaluleka okulinganayo, nakuba kungatholakali kakhulu, kukhona eminye yemiphumela yokuziphatha ngokuziphatha ngokocansi, kuhlanganise nezakhiwo ezivuzayo zokusebenzisana ngokocansi nokuthi isipiliyoni socansi sishintsha kanjani ukusebenza kahle kocansi. Lokhu kubuyekezwa kufingqa imiphumela yocwaningo lobulili ekusebenziseni imivuzo kanye nokuqhutshwa kwama-hamster aseSyria. NAma-correlates e-eural yalezi zindlela zokuxhumana ngokocansi zihlanganisa izinguquko zesikhathi eside zamaselula ekudluliseleni kwe-dopamine kanye nemigwaqo yokudlulisa i-postsynaptic ehlobene ne-plastic neuronal (isib. Ukuhlanganiswa, lezi zifundo ziphakamisa ukuthi isipiliyoni socansi sithuthukisa izindawo zokuqinisa ukuziphatha ngokocansi, okuba nomphumela ohlangene wokwandisa ukusebenza kahle ngendlela yokwandisa impumelelo yokuzala.
1. Isingeniso
"Kungani izilwane zishade naye?" Ngumbuzo olula olele enhliziyweni ye-neurobiology yokuziphatha kobulili wesifazane. Akukho mbuzo wokuziphatha onayo impendulo elula, njengoba kukhona kokubili izimbangela eziseduze neziphambene nokuziphatha okuphakamisa imibuzo yabo futhi babe nezimpendulo zabo ze-neurobiological. Mhlawumbe impendulo evame kakhulu kulowo mbuzo "Ukukhiqiza inzalo". Lokhu kungaba impendulo kumongo wokuziphatha okuphambene kokuziphatha, kodwa noma kunjalo, impendulo enjalo ngokungangabazeki ayilungile [2]. I-Agmo [2] ucacisa idatha evela kwabaseSweden ebonisa ukuthi kuphela i-0.1% ye (cishe) imiphakamiswaneni engalingani ngokobulili eveza izingane. Ngisho phakathi kwezinhlobo ezinjengamakhompi, lapho amaphesenti aphezulu okuvuthwa angabangela inzalo, ukuhlanganiswa okunjalo akusho ukuthi ukukhulelwa kulindelwe umphumela wokwenza.
Impendulo eyodwa embuzweni wokuthi kungani izilwane zithandana ngokuqondile ngendlela yokuziphatha ngokocansi njengendlela yokuphendula 'ukucabanga' ekuguqukeleni komzimba wokuzala okuhlangene nokuhambisana nesenzo esivela kumuntu okwazi ukuzala. Ukuphenywa okunjalo nge-neurobiology yokuziphatha kobulili kwabesifazane kwakusekelwe ekuqapheliseni ukuthi ukulandelana kwe-ovarian hormone ukuvezwa kwakha isimo esifanele sokuphila kwabesifazane ukuphendula ngokocansi owesilisa okhulayo [70]. Ngezinduku, izinsuku ezimbalwa ze-estradiol ukuvezwa okulandelwayo kulandelwa ukuqhuma okuqhubeka kwesikhathi kwe-progesterone eqondisa ukuvuthwa nokuziphendulela ngokobulili kumabhayisikili ngokwezemvelo [22]. I-logic esilandelayo yilapho izindawo ezikhomba ubuchopho eziqukethe ama-receptors ye-estradiol ne-progesterone zinganikeza amaphuzu agxile ekwenzeni izindlela ze-neural ezilawula ukuziphatha kobulili besifazane [70]. Ngaphezu kwalokho, izenzo zala ma-hormone e-steroid kumangqamuzana omzimba anganikeza ukuqondisisa emisebenzini yamaselula namangqamuzana ekuxhumaniseni ukubhekwa kocansi wesifazane [71]. Akungabazeki ukuthi le ndlela yokwenza uhlelo lokuziphatha ngokocansi ibe yimpumelelo enkulu, futhi imininingwane yale nurobiology ngokwemigomo yezokujikeleza, i-neurochemistry kanye nesiginali sezakhi zisekelwe kahle [isib. 6,71].
Noma kunjalo, kunesinye isici esilawula i-neurobiology yokuziphatha ngokocansi okubhekene nemiphumela yesikhathi esisheshayo neyesikhathi eside yokusebenzisana ngokocansi, okungukuthi, ukulawula okugqugquzelayo ukuziphatha ngokobulili kanye nemiphumela ebhekene ne-plastic neural plastic underlying this system. Le neurobiology iye yabuyekezwa yindoda, ikakhulukazi amagundane [2]. Umgomo walesi sethulo ukuhlola izinguquko ezinjalo zePlastiki kubantu besifazane, ngokugxila emsebenzini wethu nama hamster aseSyria. Kusukela kulo msebenzi, kubonakala ukuthi nakuba imiphumela ephazamisayo yokuziphatha ngokocansi ingase ibe ukukhiqiza, ukulinganisa okulinganiselwe ukuthi kusebenze izinhlelo zokugqugquzela, empeleni, ukuqhuba ukuziphatha.
I-2. Imiphumela ye-experience kumaphethini wokuziphatha kobulili wesifazane
Izinhlobo ezimbili ezinikeza umehluko omuhle wokuthi indlela yokuphila kwezenhlalakahle ezithinta ngayo imikhuba yokuziphatha ngokocansi yizintambo zaseNorway namaHamster aseSyria. Zombili lezi zilwane zihlala ohlelweni lwe-burrow. Phakathi kwalawo minyango, amagundane anesakhiwo esiyinkimbinkimbi sezenhlalo esinezizukulwane eziningi zesilisa nabesifazane [3], kanti i-hamster yabantu abadala (kokubili owesilisa nowesifazane) bahlala ngokwehlukana eminyangweni ngayinye [26].
Uhlelo lwezenhlalo lwamakhompi luvumela abantu abaningi abesilisa nabesifazane ukuba bahlangane ngesikhathi esisodwa [51]. Naphezu kwalolu hlelo olubonakala lukhukhumezekile, amagundane amabhinqa akwazi ukulawula iphethini lokusebenzisana ngokocansi nabesilisa ababandakanya ukukhetha ukuthi yiliphi owesilisa ozokwenza umkhankaso wokukhipha umklamo phakathi nale nqubo yezinsikazi eziningi zokuxubana [51]. Ngakho-ke, amagundane angabesifazane abahlanganyeli abathintekayo ekuxubeni futhi banikeze izindlela eziphumelelayo zokulawula iphethini lokusebenzisana ngokobulili, kufaka phakathi ukhetho lomlingani.
Inxusa yokucela ukuziphatha ngokobulili kumagundane inikeza ubufakazi obucacile bendlela abesifazane abangakwazi ngayo ukulawula ukuxhumana okuqhubekayo kocansi nabesilisa. Lapho izintuthwane eziduna zifinyelela kumfazi wesisu, owesifazane uzophendula ngephethini elinomthwalo ongenamakhanda lapho azokwenzela khona (ie, hopping) noma azenzele yena (okusho ukuthi, ukuvusela) ngaphandle kwendoda [20,49]. Lezi zinxusa, ezihlangene nokusebenza kusuka kumadoda, ukuvimbela owesilisa ekukhuliseni owesifazane aze ayeke futhi avumele ukuthintana naye [49]. Kuyathakazelisa ukuthi abesifazane bayakuvumela abesilisa ukuba bahambe futhi ngokushesha ngemva kokulandela intaba ngaphandle kokungahambisani nalokho kunokuthi uma owesifazane etholakele [20,50]. Le mithetho yokuziphatha komyeni ngamagundane wesifazane ibizwa ngokuthi 'ukuhamba phambili' futhi kunezimpendulo ezicacile zokuguqulwa kwesisu nokuzala [20,21]. Ukuziphatha okuphambene nokukhishwa kwamakhanda kumazinyane ezinsikazi kuncike ekulawulweni kwe-nucleus accumbens dopamine [4,28,29,32,33,58,84]. Ebusweni, isibonelo esiyinkimbinkimbi sokuhamba ngamazinyane wesifazane sikhombisa ukuziphatha okungahle kuguqulwe ngesipiliyoni. Idatha engatholakali etholakalayo, noma kunjalo, isikisela okuhlukile [19] nesiphetho esiphezulu [20] ukuthi "… ukuqondiswa kwengqondo kuyingxenye esizinzileyo nezelwe yokuzalwa yempendulo yezocansi elalini labesifazane" (ikhasi 482).
Njengoba kunikezwe ukuphila kwabo kwedwa, i-hamster yabesifazane inendlela ehluke kakhulu yokulinganisa, ulwazi olususelwe ekufundweni kwebholariyetha [isib. 46], kunokuba kubonwe ngemvelo. Abesifazane (kanye nabesilisa) ama-hamsters afaka iziphetho emhubheni omkhulu oholela ohlelweni lwe-burrow [26]. U-hamster wesifazane ujoyina abesilisa ngokusemthethweni ngokuvula leyo mimoya bese ebeka umzila womunwe wesitho sangasese oholela ekungeneni komngcwabo ngokulindele ukuqala kokuziphatha kwakhe u-estrus [46]. Kokubili kungaziwa ukuthi kukhona ukukhethwa komlingani nge-hamsters yabesilisa noma ukuthi ukukhethwa kowesifazane kungenziwa kanjani endle. Lapho owesilisa ehlelwa emgodini, owesilisa nowesifazane bahlala ndawonye kuze kube yilapho owesifazane efinyelela esifundeni se-estrous futhi kuqaliswa [46]. Ngemuva kokuqeda owesilisa kukhishwa emgodini wesifazane [46].
Ukungahambi kahle kwesimo sezinsikazi zesifazane se-hamster kuqhathaniswa nokushintshaniswa ngokukhululekile nabesilisa ngesikhathi sokuziphatha ngokocansi kumazinyane ezinsikazi. Ama-hamster wesifazane asheshe afake isimo esiqinile esihambisana ne-lordosis, ukuhlelwa okungagcinwa ngaphezulu kwe-95% ye-10 min test [15]. Ngenkathi owesifazane egcina lesi sikhundla, owesilisa uzokhuphuka futhi / noma ukukhuphuka nge-intromission ngokusobala ngesivinini sakhe. Isiphetho esibonakala sengathi esobala esivela kulezi zinkinga kwakuwukuthi ama-hamster wesifazane, ngokungafani namagundane amabhinqa, awahambisani nokusebenzisana ngokobulili wesilisa.
Naphezu kokubonakala kokungahambi kahle, ama-hamster wesifazane empeleni abahlanganyeli abathintekayo ekuxhumaniseni ukusebenzisana nabesilisa [46]. Ohloniphekile [62] kuqala waqaphela ukuthi ama-hamsters wesifazane enza ukunyakaza okusebenzayo kokuziphendulela ekuphenduleni ukugqugquzela okuthinta inhliziyo okuvela ku-hamster wesilisa, kanti owesifazane uyishukumisa i-perineum ekuqondiseni. Insikazi ishukumisa ubulili bayo ngokuya endaweni yokuxhumana namadoda abesilisa ukuze kutholakale ukufakwa kwangaphakathi kwendoda [62]. Eqinisweni, ukusetshenziswa kwesinye isivivinyo esihlotsheni sezinyosi ku-perineum ye-hamster yesifazane kunciphisa amandla ekwenzeni i-hamster yesilisa ukufeza ukufakwa kwe-penile [63].
Ukuhlanganiswa ndawonye, amagundane wesifazane kanye nama-hamsters ahluke ngendlela ababukeka ngayo yokulawula ukubhekana. Umehluko phakathi kwamagundane namantombazane ama-female asemandleni okulezi zilwane ukulawula ukuphakama kwesilisa. Amagundane amancane anganquma ukuthi noma owesilisa uzokwenyuka yini ngempela. Ama-hamsters wesifazane awalawuli ukuvama kwezigqoko zendoda, kodwa angathonya ukuthi noma yini owesilisa uzophumelela ngokuphumelelayo emzamweni othile okhulayo. Ngakho-ke, ukuhamba ngama rats kungabonwa kalula, kanti kunzima kakhulu ukulinganisa ukunyakaza okuqhubekayo kuma-hamsters wesifazane ngesikhathi sokubeletha. Njengesixazululo, sithatha indlela engafanele yokulinganisa indima ye-hamster yenkampani ekulawuleni ukungahambisani nendoda. Sacabanga ukuthi uma inani lezintaba ze-hamster elitholayo lithathwa yindoda, kodwa ukuphakama okufinyelele ekungeneni kokunciphisa kunqunyelwe ukuziphatha kwabesifazane, ke iphesenti yezintaba ezibandakanya ukungena (ezincwadini ezithi 'hit rate') empeleni isilinganiso sincike kakhulu ekuziphatheni kwesifazane.
Ukuze sihlole lesi siphakamiso, sihlolisise i-hamsters yabesifazane ababeyizintandane noma abesilisa ababesitholile nge-6 masonto onke, ukuxhumana kocansi nge-10 nabesilisa [8]. Sabe sesivumela umlingani wesifazane ngamunye nge-hamster yesilisa engavumayo ngokocansi futhi abhale ukuziphatha okuphambene nokuziphatha. Abesilisa abanamahloni abanjwe abesifazane abathintekayo ngokocansi babe nesilinganiso esiphezulu sokushaya (amaphesenti amakhulu ama-mounts angenawo ama-intromission) kunamadoda angamazi avivinywa ngamantombazane angama-naive (I-Fig. 1). Ngaphezu kwalokho, umehluko ofanayo nesilinganiso sokushaya wawubonakala ukuthi ngabe abesifazane bahlolwe i-1 noma ama-6 amasonto ngemuva kokuhlolwa kwabo kocansi lokugcina ngokocansi, okuphakamisa ukuphendula okuqinile okufundiwe.
Uhlolo olwengeziwe olwenzelwe i-dopamine emiphumeleni yesipiliyoni socansi besifazane ekusebenziseni ukuqhutshwa komuntu wesilisa [8]. I-dopamine neurotoxin, i-6-hydroxydopamine, yayifakwe ku-basal forebrain, kuhlanganise ne-nucleus accumbens, ye-hamsters yabesifazane ngaphambi kokuthola isipiliyoni socansi. Abesilisa abanamahloni abavivinywe nalaba besifazane abazange babonise izinga eliphakeme lokushaya elihambisana nokuxubana nabesifazane abanolwazi (Umfanekiso we-2). Umthelela we-dopamine neurotoxin ekusebenzisaneni ngokobulili wawucacile ekunciphiseni kwesilinganiso sokushaya okuhlobene nokuhlangenwe nakho kocansi, njengoba kwakungazange kube nomphumela walezi zilonda ekuziphatheni kwabantu ababili abangenalwazi nabesifazane.
I-3. Isimo socansi sinemiphumela emihle kwabesifazane
Ukuphindaphindiwe ngokocansi nabesilisa kubangela imiphumela yokuziphatha yesikhathi eside yowesifazane esimweni somvuzo. Okukhethwa kwendawo okufakiwe [14] bekuye indlela ewusizo yokuthola ukuqinisa izingxenye zokuziphatha ngokobulili. Kulesi sigaba, ukuxhumana ngokuphindaphindiwe ngokobulili nendoda kufakwe ekamelweni elilodwa ekamelweni eliphezulu. Ngezikhathi ezifanayo, owesifazane ubeka yodwa ekamelweni elifanayo kodwa elihlukile. Ngaphambi kokulandela lezi zivivinyo zokubeka isimo, owesifazane unikezwa ithuba lokuhlola lezi zixhobo (ngokungabikho kwesilisa) ukucacisa inani elilinganayo lezinsikazi ezihlala egumbini elihambisana nokuqubuzana. Ukuqhathaniswa nendoda kufakwa ngokucacile njengokuqiniswa uma owesifazane echitha isikhathi esiningi kakhulu ekamelweni elihlobene nokulingana emva kokulingwa kobulili kunokuba ngaphambi kokumiswa.
Umphumela ocacile (nakuba mhlawumbe ungaqiniseki) walezi zifundo ngamagundane wesifazane [isib., 65,69] nama-hamsters [56] ukuthi ukuxhumana kocansi kuqinisa. Izidingo zokugqugquzelwa kwalesi sifo ukuba zenzeke zazingekho. Ngoba ama-rats noma ama-hamsters akuyona into elula ye-lordosis phakathi nokuhlolwa kokulinganisa okwanele ukwenza indawo ekhethwe kahle. Njengoba kuphawuliwe, amagundane asifazane anesilinganiso esithandwayo soxhumana nabo ocansini nomuntu okhulayo onomphumela we-neuroendocrine ohlobene nokuguqulwa nokuzala. Ukuvumela amagundane amabhinqa ukuba ahambe ngesigaba sabo esikhethwayo kuyadingeka ukuze kutholakale indawo okumele ibekwe kuyo, njengokusebenzisana ngokocansi lapho insikazi engahambi khona ingakhiqizi isimo [25,27,34,67,68]. Iphethini yesikhashana lapha ibalulekile, nakuba kungenjalo ngempela ukulawulwa kokuhamba phambili, njengokulawula ukuhamba ngokususa nokuletha owesilisa ngesikhathi sokukhethwa kwabesifazane kuzoholela ekutheni isimo sendawo sithandwa [34].
I-hamsters yabesifazane ayinayo imfuneko yesikhashana yokulingana [42], nakuba babonisa indawo ehlelekile yokuthanda ukulingana [56]. Enye indlela okubaluleka ngayo oxhumana nabo ocansini ngokobulili ngokubeka isimo sezintandokazi ezihlolwe kuma-hamsters wesifazane kwakuwukuqhathanisa ukusebenza kwezokuxhumana ngokocansi okuvamile nokusebenzisana ngokocansi lapho kuvinjelwe khona ukuhlukunyezwa komuntu wesilisa ngokuvimbela owesifazane wesifazane [39]. Lapha, faka isimo sokuthandana kubonakala kungakhathaliseki ukuthi u-feminine uthola ukuvuselelwa kwesisu ngesikhathi sokuhlolwa kwesimo sokuziphatha ngokocansi. Lo mphumela wokuhlola ubonakala uphambana nokuqaphela ukuthi ukuvotelwa okwesilisa okufanayo kuvimbela ukuphakama ekuqongeni i-dopamine ngesikhathi kusebenzisana ngokobulili nendoda [40]. Kodwa-ke, labesifazane babengenalo ubulili kulolo cwaningo lwe-microdialysis. Kubonakala sengathi ubuningi bezinto ezithinteka ngesikhathi sokulwa nesimo socansi, isibonelo ngesikhathi sokuhlolwa kwesimo se-paradigm yezindawo [39], ikhulisa umqondo ovelayo owenza umvuzo wezocansi kusukela endimeni engavinjelwe yokugqugquzelwa kwesisindo kumantombazane angenayo ubulili [40].
Kube khona uphenyo oluthile lwezinhlelo ze-neurotransmitter ezixhumanisa indawo yokuthanda ukuthanda ukuxhumana. Esinye isifundo, ukuphikisana neurotransmission nge-opioid neurotransmission ngokuphatha ama-rats ezinsikazi nge-naloxone ngaphambi kokusebenzisana ngokocansi kuqeda isimo sokuthanda indawo [68]. Ngakolunye uhlangothi, izifundo eziningana zisebenzisa ama-dopamine receptor antagonists ziye zaveza imiphumela ehlanganisiwe. Ukuqothula ama-hamster wesifazane ne-dopamine abaphikisi be-D2 abamukelayo [57] avimbele ukutholakala kwendawo enesimo esifanele ukuthanda ukuxhumana ngokocansi (I-Fig. 3). Ucwaningo olufanayo kumagundane aluzange lube nomphumela [30].
I-4. I-neurotransmitter ne-plastiki yeselula elandela isipiliyoni socansi kwabesifazane
Kukhona isiko elicebile locwaningomgomo ezindleleni zokubonakaliswa kwe-dopamine njengoba zihlobene nezingxenye zokuziphatha okukhuthazayo nokusebenzisa kabi izidakamizwa [isib. 60]. Ukubolekisa kulezo zincwadi, sasihlola ukuthi kungenzeka ukuthi ukulwa nobulili kungathinta i-dopamine neurotransmission endleleni ye-mesolimbic futhi ukuthi i-plasticity kuleso simiso yayiyisisekelo semiphumela yokuziphatha ngokobulili, isib. Izinguquko ekusebenzeni ngokucophelela nokuvuza. Ngaphansi kohlelo lwe-dopamine lwe-mesolimbic kukhona bobabili ubufakazi bokuthi kusebenze ngesikhathi sokusebenzisana kobulili, kanye nemiphumela yesikhathi eside kwi-plasticity ye-structural and neurochemical. Ukuhlolwa kokuqala kwe-microdialysis kubonise ukuthi amazinga e-extracellular dopamine ku-nucleus accumbens yamantombazane aphakanyisiwe ngesikhathi sokubuthana [55,58]. Amakatikazi wesifazane, ukukhululwa kwe-dopamine kwakuzwela kakhulu ekusebenzisaneni okuhambisana nokuhamba ngamantombazane [4,33,58], futhi (okungenani okungezansi ngokobulili) ama-hamster wesifazane, ukuphakama kwe-dopamine kuye kuxhomeke ekuvuseleleni kwesisindo esitholwe ngesikhathi sokubeletha [40]. Inokuzama ukulandela okulandelayo sithatha indlela ehlukile, ngalesi sikhathi silinganisa i-dopamine ye-extracellular ku-nucleus accumbens ngesikhathi sokuthandana kwama-hamster wesifazane angenayo ubulili noma kwabesifazane ababenokuhlangenwe nakho kocansi ngaphambi kokuhlolwa kwe-microdialysis [38]. Okuhlangenwe nakho ngokobulili kwaveza ukwanda okwedlulele kwe-extracellular dopamine eqhubekayo phakathi nokuxhumana kocansi nendoda, uma kuqhathaniswa namazinga e-dopamine kuma-sexually-females (Umfanekiso we-4). Mhlawumbe ukuphendula kwe-dopamine okwandisiwe kuma-sexually experienced experiences kubonisa ukuthi kuhlanganiswe ukuhlanganiswa okuhlangene okuhambisana nalokho okushiwo ama-hamsters wesifazane ngenxa yalokho okuhlangenwe nakho.
Ukuphakama kwe-dopamine ukukhululwa kuma-hamsters wesifazane okuhlangenwe nakho kuyakhumbuza imiphumela yokuvezwa ngokuphindaphindiwe kwezilwane kwizidakamizwa zokuhlukunyezwa [75]. Kulezi zincwadi, izinga eliphakeme le-dopamine ekuphenduleni umthamo ohleliwe wezidakamizwa kuthiwa "ukuzwela" [75]. Ukuzwela izidakamizwa kuhambisane nezinhlobonhlobo zezimpendulo zamaselula ezicatshangelwe ukuthuthukisa ukusebenza kwe-synaptic kanye nolwazi olugelezayo endleleni ye-mesolimbic [74].
Ookungenayo ingeniso ekusebenziseni indlela yokuziphatha okungashintsha i-plastic neuronal ezingeni le-synapses. Indlela engacacile yalo mbuzo ithathwe ngokulinganisa izinguquko ze-dendritic ku-striater (kuhlanganise ne-nucleus accumbens) neurons ekuphenduleni ukuphathwa kwezidakamizwa noma ngokulandela isipiliyoni sokuziphatha. Ukuphathwa okuphindaphindiwe kwezidakamizwa ezihlukahlukene ezihlukunyezwe ngamaphrofayli ahlukene e-pharmacy kuzothuthukisa ubude be-dendritic kanye / noma ubukhulu bomgogodla emagatsheni ase-dendritic asezingeni eliphansi lama-neurons aphakathi [13,23,44,45,64,76,77,78]. Kunezibonelo ezimbalwa ezenzelwe ukuhlangenwe nakho okuziphatha okukhiqiza imiphumela efananako kuma-dendrites, nakuba ukufakelwa kosawoti [79], ukuziphatha ngokobulili wesilisa [24] nokuziphatha kobulili wesifazane [59] izoshintsha i-dphoritic morphology ezinhlangothini eziphakathi kwezinkanyezi ze-nucleus accumbens.
Okuhlangenwe nakho ngokocansi kuma-hamster wesifazane kunomthelela ohlukile kumdlandla we-dendritic spine [59] kuye ngokuthi isifunda sihlolwe (I-Fig. 5). Kulesi sivivinyo, ama-hamster wesifazane anikezwe ipharadamu yethu eyisisekelo yamaviki e-6 okuhlangenwe nakho kobulili noma ahlale engavumelani nobulili [38]. Ku-7th isonto, bonke abesifazane banikezwa i-estradiol kanye ne-progesterone priming regimen futhi banikela nge-4 hr ngemuva komjovo we-progesterone. Ama-Brains asetshenziselwa ukukhishwa kwe-Golgi kanye no-240 μm tincetu. Ama-spines ayebalwa kusukela kumagatsha okugcina e-terminal dendritic we-pyramidal neurons e-prefrontal cortex, e-spin ne-spin medium (nucleus accumbens), ne-neurons ephakathi kwe-corsate ye-dorsal. Ngaphakathi kwe-neurons ephakathi kwe-nucleus accumbens, i-dendritic spine density (ejwayelekile kuya ku-10 μm yobude be-dendritic) yayiphakeme kakhulu ekuziphatheni ngokobulili, kunokuba ku-naive ngokobulili, abesifazane. Umkhulumiswano watholakala kuma-dicrites e-apical we-layer ne-neurons we-prefrontal cortex. Kwakungekho ukuhlukana kweqembu emgodini wesibindi emaphethini e-spin ne-spid medium. Sichaza lo mqondo ohlukile emthonjeni we-spine njengoba uboniswa nge-plasticity ekungeneni kwe-neurotransmission kuma-neurons e-dopaminergic-aphendule [37].
Uma sithatha i-plasticity kumagqabha e-dendritic njengamakhamera eselula ahlangene nesipiliyoni socansi, singaphakamisa ukuqhuma kwezigameko zamaselula ezibangelwa ukusebenzisana ngokocansi okuphindaphindiwe. Ngamanye amazwi, ukugxila kufanele kube kumakilasi amabili eempendulo eziboniswa ukwelashwa nezidakamizwa zokuhlukunyezwa [36], okungukuthi, impendulo ephoqelekile ekuziphatheni ngokocansi kanye nezimpendulo zamaselula ezishintshile ngokungabikho kokuziphatha ngokocansi. Izenzakalo zokufakazela ezihlongozwayo zikhonjisiwe I-Fig. 6. Lesi siphakamiso asiyona inkaba noma ayinamandla, njenge-plastic dentritic evela ekuthandeni njengama-hormone ahlukahlukene e-steroid [54], izidakamizwa zokuhlukunyezwa [61], noma amandla okuhlala isikhathi eside [1] konke kuhilela imicimbi efanekiselwe. Kungenxa yokuthi lezi zindlela zimelelwe kahle ezinhlobonhlobo ezihlukahlukene ze-plastic wall neural ukuthi kubonakala sengathi njengoba izikhala zigcwele ngendlela efanayo kuzoba nemiphumela emibi yokuziphatha ngokocansi ku-nucleus accumbens.
Indlela yokuthola, esebenzisa ama-microarrays wegenes [7], kanye nezinyathelo zokuhlola seziqalile ukwenza umsebenzi oshintshiwe noma ukukhulumisana kwamaphrotheni kumaphuzu amaningana kulezi zindlela ezibangelwa isipiliyoni socansi. Izici zokubhala zimelela iqoqo elilodwa lemicimbi yamangqamuzana engathinta isakhiwo se-dendritic esiholela epulasitiki yesikhathi eside [5,17,52]. Zombili c-Fos noFosB staining babhekwa ngokuphendula isipiliyoni socansi nokuzibandakanya kuma hamster aseSyria. Ukulandela ukusebenzisana ngokobulili nendoda, i-c-Fos staining yaphakanyiswa emkhakheni we-nucleus accumbens, impendulo ephakanyisiwe kwabesifazane abanolwazi ngobulili (I-Fig. 7) [9]. Ukukhwabanisa kwe-FosB akuzange kuthinteke ngokuphawulekayo ngokusebenzisana ngokocansi, nakuba amazinga okugcoba ayephezulu emkhakheni we-nucleus accumbens kuma-hamster wesifazane ocanshangelwa ngokocansi uma kuqhathaniswa nama-naïve abesifazane (I-Fig. 8). Abe-c-Fos noma i-FosB abathintekile ukuziphatha ngokobulili noma isipiliyoni socansi kugobolondo le-nucleus accumbens noma i-dorsal striatum kulaba besifazane. Ekuhlolweni kwethu, izinguquko ku-c-Fos ne-FosB zenzeka ngokufanayo, kokubili esifundeni nasemisebenzini yocwaningo, nakuba kwezinye izifundo ezishintshayo kulezi zinhlelo zamaprotheni azihlali njaloy [isib, 12].
Amaprotheni angama-Fos angenziwa kusebenze ngezindlela ezimbalwa zokubonisa, kuhlanganise MAP kinase [18]. I-ERK iyi-downsearch kinase kule ndlela futhi sihlolisise ukulawulwa kwe-ERK ngokulandela ukuziphatha ngokobulili (I-Fig. 9). Ema-blots ase-Western, amazinga we-ERK angu-2 ayengathinteki ngokuziphatha kobulili noma nesipiliyoni socansi. Ngokuphambene nalokho, i-PERK 2 yaphakanyiswa ku-nucleus accumbens emva kokuziphatha ngokocansi, kodwa kuphela kwabesifazane abanezimo zangaphambi kocansi.
Ukungena kumzila we-MAP kinase kungavela emithonjeni eminingana, kufaka phakathi ukusebenza kwe-receptor glutamate [1], Ama-G-amaprotheni ahlangene nama-receptors (isb., I-dopamine receptors) [83], i-inositol triphosphate indlela [66], futhi ngokusebenzisa ukukhula kwezinto zokwamukela [16]. Imiphumela yecala lokuzibandakanya ngokocansi kulezi zindlela kuye kwacatshangelwa ngokuhlaziywa kwe-microarray [7], kodwa akukahlolwa ngokuqondile ngqo. Enye indlela eqinisweni ilawulwa yilokho okuhlangenwe nakho kobulili i-dopamine receptor ukuxhuma ku-adenylate cyclase [10]. Ama-homogenates avela ku-nucleus accumbens athathwa kuma-hamsters wesifazane ocanshangelwa ngokobulili noma angenalwazi. Lawa ma-homogenates avuselelwe i-dopamine kanye nokuqoqwa kwe-cAMP kulinganiswa (I-Fig. 10). I-Dopamine yakhuthaza ukuqoqwa kwe-CAMP kuyo yonke amaqembu okwelapha, ngokuvuselela okukhulu ekuhloliseni okuvela kubantu besifazane abanolwazi oluthandana ngokobulili. TIzenzo ze-dopamine zenzelwe ukuba yi-D1 receptor elamuliwe. Nakuba ingxenye eyodwa ye-plasticity elandela isipiliyoni socansi i-presynaptic (okungukuthi, ukwanda kwe-dopamine efflux ngesikhathi sokuxhumana kocansi), kucaca ukuthi kukhona ukuguqulwa kwe-postsynaptic okungewona nje ukuboniswa kwamazinga we-synaptic dopamine.
I-5. Isifinyezo nesiphetho
Esinye isici se-mesolimbic dopamine umsebenzi wukuthi le ndlela igxile ezakhiweni ezifakiwe ezihambisana nokuziphatha okwenzeka ngokwemvelo ngendlela eyenza imiphumela ephumelelayo yalezo ziziphatha ziphumelele [80]. Kusukela kuloluhlaka singakwazi ukucabanga ngesimo sokuziphatha lapho ukuvuthwa kwamagciwane okwamukelwa ngabesifazane ngesikhathi sokubambisana kuvuselela i-dopamine neurotransmission. Nakuba ekuqaleni le mpendulo ayinqatshelwe [55], okuhlangenwe nakho kwebesifazane bafunda ukukhiqiza izinyathelo ezicashile ze-perineal ezandisa amathuba okuthola isisindo samadoda kumuntu okhulayo [8]. Kanti, kune-activation enkulu ye-dopamine, edla phambili ukugcina ukuphendula kokuziphatha. Ngoba ukwamukela ukuvuselelwa kwesidoda ngokususwa kwamagciwane avela kumuntu okhulayo (ukuguqulwa kwangaphambili kwesilisa) kuyadingeka ukuze kuhlanganiswe isimo se-progestational esihambisana nokukhulelwa (ngakho-ke ukukhulelwa okuphumelelayo) [42], lo mthethonqubo wokuziphatha uzoba nomthelela ongacacile wokwandisa ukusebenza kahle okuholela ekuphumeleleni kokuzala. Impendulo yombuzo othi "Kungani abesifazane besondelene?" Ukuthola ukwesekwa okuba nemiphumela emihle ngendlela yokwenza umsebenzi we-forebrain dopamine. Lezi zici 'ezithokozisayo' zokuziphatha ngokobulili zingenakulindelekile (kusukela kwimbono yabesifazane), nakuba ziguquguquka kakhulu, imiphumela yokukhulelwa okuphumelelayo nokuzalwa kwenzalo.
Ukuvuma
Sithanda ukubonga inani labantu abanikele ngokubaluleka kulolu cwaningo kubandakanya uDkt. Katherine Bradley, u-Alma Haas, uMargaret Joppa, uDkt. Jess Kohlert, uRichard Rowe noDkt Val Watts. Sibonga ngokukhethekile kuPaul Mermelstein ngeseluleko sakhe futhi nesithakazelo esiqhubekayo emsebenzini wethu. Lokhu kubuyekezwa kusekelwe enkulumweni enikezwe kwi-2006 Workshop kwi-Steroid Hormones noBrain Function, Breckenridge, Co. Sibonga i-National Science Foundation (IBN-9412543 ne-IBN-9723876) kanye neZikole Zikazwelonke Zempilo (DA13680) yazo ukusekelwa kwalolu cwaningo.
Okubhekwayo
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