Specialized membrane junctions in the avian cerebellum

Summary Pentalaminar specialized membrane junctions-tight junctions — are described in the granular layer of the pigeon cerebellum. The presence of these axo-dendritique and dendrosomatic contacts suggest the existence of electrotonic coupling in the pigeon cerebellum.This work received financial support from the Instituto de Alta Cultura, Lisbon, Project No. PMC5-I.Acknowledgements. I am greatly indebted to Prof.E. G. Gray and Prof.A. Sousa Pinto for helpful advice and criticism. The technical assistance of Mrs.M. M. Pacheco, M. G. Rodrigues, M. L. Brito and Mr.Bessa Nunes is gratefully acknowledged.