Cholinergic nerves in the parietal pleura

Using the Cholinesterase histochemical technique we investigated the innervation pattern of parietal pleura both in normal and chemically sympathectomized rats. AChE containing nerve fiber-like structures were observed within the parietal pleura. The apex, costal, and mediastinal surfaces of the pleura are poorly innervated, while the diaphragmatic pleura shows the richest innervation. In relation with thicker nerve fiber-like structures the existence of some elbow shaped AChE positive formation was observed. The chemical sympathectomy does not causes alterations in the distribution of AChE containing nerves in the pleura. The meaning of cholinergic innervation of parietal pleura is discussed.