Peptide C (C-peptide) na insuline (insuline) ni molekile ebyiri zikorwa n’uturemangingo tw’udukoko twa pancreas mu gihe cyo gukora insuline. Itandukaniro ry’aho ikomoka: C-peptide ni umusaruro w’ikorwa rya insuline n’uturemangingo tw’udukoko. Iyo insuline ikozwe, C-peptide ikorwa icyarimwe. Kubwibyo, C-peptide ishobora gukorwa gusa mu turemangingo tw’udukoko kandi ntizakorwa n’uturemangingo turi hanze y’uturemangingo. Insulini ni yo misemburo nyamukuru ikorwa n’uturemangingo tw’udukoko twa pancreas hanyuma ikajya mu maraso, igenzura urugero rw’isukari mu maraso kandi igatuma isukari ikwirakwira no gukoreshwa. Itandukaniro ry’imikorere: Inshingano nyamukuru ya C-peptide ni ugukomeza kuringaniza hagati ya insuline na receptor za insuline, no kugira uruhare mu gukora no gusohora insuline. Urugero rwa C-peptide rushobora kugaragaza mu buryo butaziguye imikorere y’uturemangingo tw’udukoko kandi rukoreshwa nk'ikimenyetso cyo gusuzuma imikorere y’uturemangingo. Insulini ni yo misemburo nyamukuru ya metabolisme, iteza imbere kwinjira no gukoreshwa kwa glucose n’uturemangingo, ikagabanya urugero rw’isukari mu maraso, kandi ikagenzura inzira ya metabolisme y’ibinure na poroteyine. Itandukaniro ry’urugero rw’amaraso: Urugero rw’amaraso rwa C-peptide rurahamye kuruta urugero rwa insuline kuko rugenda buhoro. Igipimo cya insuline mu maraso kigirwaho ingaruka n'ibintu byinshi, harimo kurya ibiryo mu nzira y'igifu, imikorere y'uturemangingo tw'inyama, kudakora neza kwa insuline, nibindi. Muri make, C-peptide ni umusaruro wa insuline ukoreshwa cyane cyane mu gusuzuma imikorere y'uturemangingo tw'inyama, mu gihe insuline ari yo misemburo ikomeye ikoreshwa mu kugenzura amaraso.