C3 and complement component 3 deficiency: To investigate whether the laxative effects of Urd and AEtLP in C3-deficiency-induced constipation were accompanied by an improvement in the ENS function, the alteration in the composition of neuronal cells and the excitatory and inhibitory function of the ENS were measured in the mid colon of C3 KO mice treated with Urd and AEtLP.