Fluorescence studies on neural structures and endocrine cells in the pancreas of the cat

Summary With the use of the Falck-Hillarp histochemical technique for the detection of monoamines, nerve fibre fluorescence is observed throughout the tail of the pancreas of the cat and the arrangement and distribution of the nerve fibres can be studied in both the exocrine and endocrine tissue. In the exocrine pancreas, adrenergic nerve fibres innervate arterioles, larger veins and major pancreatic ducts. Adrenergic nerve fibres also appear to terminate on the non-adrenergic nerve cell bodies of the intrapancreatic ganglia. In the islets of Langerhans, adrenergic nerve fibres innervate both the endocrine cells and blood vessels. Some of the islet cells exhibit fluorescence with the Falck-Hillarp technique and these cells have been identified as alpha cells. In animals treated with reserpine, the fluorescence in nerve fibres and in alpha cells is absent.The author wishes to thank ProfessorG. C. Schofield and Dr.G. C. Smith for their encouragement and valuable criticism during the course of this study. The assistance of MissJ. Bennett and MissW. Kemp and the photographic help of Mr.J. S. Simmons, F.R.P.S., are gratefully acknowledged. The diagram was drawn by MissS. Flett.