Imfihlo Yesidoda Esivundisayo
Ukuze kuqondwe kangcono izimbangela zokungabi nenzalo kwabesilisa, ithimba labacwaningi base-Bay Area selibe liphenya izinto ezithinta kokubili ezomzimba nezamakhemikhali ezihlukanisa isidoda esinempilo nesisingenampilo. Emhlanganweni wama-58 we-Biophysical Society, owabanjwa ngoFebhuwari 15-19, 2014, eSan Francisco, eCalifornia, ithimba lethule umsebenzi walo wokuhlonza nokuchaza amaprotheni aziwa njengama-ion channels, abaluleke kakhulu ekuzaleni kwesidoda futhi atholakala ngaphakathi kogobolondo wolwelwesi lweseli yesidoda (plasma membrane).
"Yonke imininingwane etholakala kulo mkhakha ingasiza ukudala ukuhlolwa nokwelashwa okudingeka kakhulu kokungabi nenzalo kwabesilisa, okuwumkhuhlane ongaziwa kahle imbangela yawo, ngoba njengamanje amaphesenti angama-80 ezimo zokungabi nenzalo kwabesilisa awakwazi ukutholakala kahle noma ukwelashwa," kusho uMelissa Miller, ongumfundi we-postdoctoral. UMiller usebenza emalabhorethri womuntu oyibhali naye, uPolina Lishko wase-University of California, Berkeley (UCB), kanye noYuriy Kirichok wase-University of California, San Francisco (UCSF).
Ukuze bafunde ama-ion channels, abacwaningi baqopha umsebenzi kagesi wama-ion channels esidoda ngaphansi kwezimo ezilawulwa ngokuqinile.
"Amalabhorethri ethu asechaze ama-ion channels amathathu anesibopho sokulawula i-calcium (CatSper), i-potassium (Slo1), kanye nama-proton (Hv1) ngaphakathi kwamangqamuzana esidoda," kusho uMiller. "Kuze kube manje, oselucwaningwe kakhulu yi-sperm cation channel i-CatSper, evele kuphela kumaseli esidoda futhi emele ithagethi efanelekile yokuthuthukiswa kwekhontrasepthivu elisebenzayo kubobabili abesilisa nabesifazane; akukho olunye uhlobo lweseli emzimbeni olwaziwayo ukuthi luveza leli protheni."
"Muva nje sibhikeze ukuthi ihomoni yabesifazane i-progesterone ivuselela i-CatSper ngendlela engeyona eyogciwane (non-genomic pathway). Kusidoda esivamile esinempilo, umsebenzi we-CatSper ukhuphuke kakhulu lapho kufakwa i-progesterone. Nokho, ukuqopha nge-patch clamp kumaseli esidoda avela ezigulini anokusulwa kwe-CatSper akubonanga mpendulo ku-progesterone futhi awuzange ukhiqize ngisho nokugeleza okuyisisekelo kwe-CatSper," kusho uMiller. "Lokhu kukhombisa ukulawulwa okuqondile kwe-channel ye-CatSper kusidoda somuntu amahomoni e-steroid.
"Amahomoni e-steroid alawula imisebenzi eyisisekelo yezamzimba kokubili ngezindlela ezijwayelekile ezisuselwe kumagciwane (genomic) kanye nalezo ezingajwayelekile, ezingezona ezamagciwane (nongenomic). Ucwaningo lwangaphambilini lukhombisile ukuthi ukuhanjiswa kwezimpawu okungelona okwegciwane kudlala indima ebalulekile ekuvuseleleni kwamaseli esidoda omuntu nasekulawuleni umuzwa wobuhlungu ngaphakathi kwama-neuron esiphondo somgogodla. Ngenxa yokuthi izinto zamangqamuzana ezibandakanyekayo kulo mzila azikaqondwa kahle, ithimba likaMiller lisebenza ekudaluleni ngqo uchungechunge lokuhanjiswa kwezimpawu zamangqamuzana (molecular signaling cascade) olwenzeka kumaseli esidoda nakuma-neuron lapho kunikezwa i-progesterone.
"Ukungabibikho komsebenzi we-CatSper kuhlotshaniswa kakhulu nokungabi nenzalo kwabesilisa, ngakho-ke ukutholwa kwalesi sithunywa sangaphakathi somzimba (endogenous signaling molecule) kungasinika uphawu olusha (biomarker) lokuzala kwabesilisa olungase lusetshenziswe ngokushesha emitholampilo njengendlela yokuhlola ngokushesha amandla okuchumisa isidoda," kusho uMiller.
Ngokubanzi, ulwazi olutholwe ezifundweni zaleli thimba lungasetshenziswa ekuthuthukisweni kwezindlela ezintsha zokuphatha ubuhlungu, kanye nokuhlolwa nokwelashwa kokungabi nenzalo kwabesilisa esikhathini esizayo.
