[Changes in cholinergic innervation in the human oviduct during pregnancy]

Using a neurohistochemical method for visualization of ACHE positive nerves according to El Badawi and Schenk (5), the authors investigated the distribution of the cholinergic innervation in the oviducts of pregnant women. The cholinergic nerve fibres were present in the oviducts during all trimesters of pregnancy. ACHE positivity of nerve structures in the musculature did not display substantial changes. On the other hand, the authors observed in the mucosa of the oviduct marked changes. In the first trimester they found few cholinergic fibres, in the second and third trimester the number of cholinergic nerve fibres increases. The findings provide evidence that the cholinergic innervation of the mucosa of the oviduct is oestrogen dependent. It will be necessary to elucidate the problem of increasing ACHE positivity of nerve structures during pregnancy by further observations.