Information

Neuroendocrinology and cellular endocrinology

John F Morris MB ChB MD

University Lecturer and Professor of Human Anatomy
Tel.: 01865 272169
Fax: 01865 272420
Email: john.morris@anat.ox.ac.uk

Endocrine cells and neurons producing peptides secrete the peptides via the regulated pathway. We seek to discover how, on stimulation, only a subset of secretory cells is responsive and peptide is released at specific sites of the cell membrane. We use quantitative light and electron microscopy with immuno- and in situ identification of peptide production, assay of hormone release by RIA and reverse haemolytic plaque assay of single cells, in vivo and in vitro manipulation of hormone release; visualisation of exocytosis, tissue culture and molecular biology techniques.

We study the hypothalamo-neurohypophysial system which has proved a robust archetype for the study of neuropeptides. Currently we examine the control and role of release of peptides from the dendrites, and local synthesis within dendrites; in particular, rapid non-genomic effects of steroids and neurotransmitter control of dendritic peptide release. This is important in peptidergic cross-talk between neurons and functional neuron-glial plasticity of the system. We examine the production by some neurons of hybrid oxytocin/vasopressin molecules resulting from somatic mutation and seek to discover why these accumulate in the rough ER in the cells as age increases.

We also study anterior pituitary endocrine cells, in particular gonadotrophs and lactotrophs. GnRH causes release of hormone not only from gonadotrophs but also from a sub-population of lactotrophs, and the release is almost restricted to the vascular pole of the cells (arrows in the figure below). Here, too, we study non-genomic actions of steroids to release prolactin. Stress rapidly inhibits the secretion of hormones via glucocorticoids; an annexin - lipocortin 1 - located predominantly in folliculo-stellate cells, mediates this inhibition by a mechanism that waits to be discovered.

Current Funding: Wellcome Trust, MRC, BBSRC, Anatomical Society.

Other Activities: Fellow, St Hugh's College

Exocytosis of prolactin granules from a type II lactotrophe in response to the non-genomic rapid action of estradiol

Large sacs of rough endoplasmic reticulum in a vasopressin neurone in which somatic hybridization crossover of the vasopressin and oxytocin genes has occured.

Key Publications
Morris JF et al. (1997) In "Neurosecretion: Retrospect and Perspectives". H-W Korf and K-H Usadel, eds. Springer, Berlin, 71-85.
Wang H, et al (1999) Neuroscience 88:151-158
Budd TC, and Morris JF (1997) J. Neuroendocrinol. 9:873-878
Christian HC et al (1997) Endocrinology 138:5341-5351
Traverso V, et al (1998. J. Cell. Sci. 111:1405-1418

Main Collaborators
Professor J Buckingham, Imperial College.
Professor M Castel, Hebrew University, Jerusalem.
Dr H Christian, Oxford
Professor G Ju, Institute of Neuroscience, Xi'an.
Professor DG Richter and Dr E Mohr, Molecular Biology Institute, Hamburg.
Professor Höhne, IMCSM Hamburg.
Professor M. Kawata, Kyoto

Group Members
Mrs Alicia Loreto-Gardner (Secretary)
Ms Sarah Rodgers (Technician)
Mrs Lynne Scott (Technician)
Dr Valerie Traverso (Research Assistant)