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Stewart Sage, MA, PhD, ScD.


Reader in Cell Physiology, Fellow of Selwyn College
Tel: +44 (0)1223 333870, Fax: +44 (0)1223 333840, E-mail:

I am a Reader in Cell Physiology and give courses on Renal Physiology and Body Fluid Homeostasis in IA NST Physiology of Organisms, IB NST Physiology and in Module P8 of Part II Physiology, Development & Neuroscience. I also contribute lectures on Calcium Signalling to Module P1 of the Part II PDN course.

I serve on the Editorial Board of Cell Calcium and am a past Chairman of the Editorial Board of the Journal of Physiology. I am a Trustee of the Physiological Society, serving on the Council and the Meetings and Nominations subcommittees.

I am a Fellow of Selwyn College, where I am a Tutor and Director of Studies in Biological Natural Sciences. I am also a Director of Studies in Medicine at Magdalene College. I supervise in IA MVST Homeostasis, IA NST Physiology of Organisms and IB NST Physiology.

Other than Physiology, I am interested in tiddlywinks, real ale and music. I am Senior Treasurer of CU Tiddlywinks Club, CU Real Ale Society and CU Concert Band. I am Vice-Chairman of the English Tiddlywinks Association and an Associate of the London College of Music in trombone playing.

Research Interests

My work focuses on intracellular calcium signalling mechanisms and the roles of calcium signals in platelet function. Much of my work has concerned the mechanisms which generate calcium entry and in particular on the mechanisms which couple the depletion of the intracellular calcium stores to the activation of calcium entry. This work employs fluorescent indicators and protein chemistry. Most recently, working with Dr Alan Harper (a former Research Fellow in my lab and now at the School of Medicine, Keele University), I have been studying platelet calcium signalling at a systems level by investigating agonist-evoked changes in the concentration of calcium and ions which influence calcium movements, in various cellular and pericellular compartments (see Sage et al., 2011 and Sage et al., 2013, below).

As well as Alan Harper, I collaborate with Drs Gavin Jarvis and Mike Mason (PDN), Prof. Richard Farndale (Department of Biochemistry, University of Cambridge), Dr Nick Pugh (Department of Life Sciences, Anglia Ruskin University, Cambridge), Dr Juan Rosado and colleagues (Department of Physiology, University of Extremadura, Spain) and with Prof. Johan Heemskerk (University of Maastricht, The Netherlands).


Original papers published over the last 10 years:


Sage SO, Pugh N, Farndale RF & Harper AGS. (2013). Pericellular Ca2+ recycling potentiates thrombin-evoked Ca2+ signals in human platelets. Physiological Reports 1, e00085.

Sage SO, Jarvis GE, Jardín I, Rosado JA, Harper AGS. (2013). The TRPV1 ion channel is expressed in human but not mouse platelets. Platelets [E-pub ahead of print].


Lopez E, Jardin I, Berna-Erro A, Bermejo N, Salido GM, Sage SO, Rosado A. & Redondo PC. (2012). STIM1 tyrosine-phosphorylation is required for STIM1-Orai1 association in human platelets. Cellular Signalling 24, 1315-1322.


Sage SO, Pugh N, Mason MJ & Harper AGS. (2011). Monitoring the intracellular store Ca2+ concentration in agonist-stimulated, intact human platelets using Fluo-5N. Journal of Thrombosis and Haemostasis. 9, 540-551.


Harper MT, Mason MJ, Sage SO & Harper AGS. (2010). Phorbol ester-evoked Ca signaling in human platelets is via autocrine activation of P receptors, not a novel non-capacitative Ca entry. Journal of Thrombosis and Haemostasis 8, 1604-13.

Harper MT & Sage SO. (2010). Src family tyrosine kinases activate thrombin-induced non-capacitative cation entry in human platelets. Platelets 21, 445-450.


Harper AGS, Brownlow SL & Sage SO. (2009). A role for TRPV1 in agonist-evoked activation of human platelets. Journal of Thrombosis and Haemostasis 7, 330-339.

Harper AGS, Mason MJ & Sage SO. (2009). A key role for dense granule secretion in potentiation of the Ca2+ signal arising from store-operated calcium entry in human platelets. Cell Calcium 45, 413-420.

Gilio K, Munnix IC, Mangin P, Cosemans JM, Feijge MA, van der Meijden PE, Olieslagers , Chrzanowska-Wodnicka MB, Lillian R, Schoenwaelder S, Koyasu S, Sage SO, Jackson SP & Heemskerk JWM. (2009). Non-redundant Roles of Phosphoinositide 3-Kinase Isoforms alpha and beta in Glycoprotein VI-induced Platelet Signaling and Thrombus Formation. Journal of Biological Chemistry 284, 33750-33762.


Redondo PC, Salido GM, Pariente JA, Sage SO, Rosado JA. (2008). SERCA2b and 3 play a regulatory role in store-operated calcium entry in human platelets. Cell Signalling 20, 337-346.

Harper MT & Sage SO. (2008). Is calcium-independent phospholipase A2 required for store-operated calcium entry in human platelets? Journal of Thrombosis and Haemostasis 6, 1819-1821.

Redondo PC, Rosado JA, Salido GM, Sage SO. (2008). Protein complex immunological separation assay (ProCISA): a technique for investigating single protein properties. Journal of Physiology and Biochemistry 64, 169-177.


Harper AGS & Sage SO. (2007). A role for the intracellular protease calpain in the activation of store-operated calcium entry in human platelets. Cell Calcium 41, 169-178. 

Harper AGS & Sage SO. (2007). A key role for reverse Na+ /Ca2+ exchange influenced by the actin cytoskeleton in store-operated Ca2+ entry in human platelets: Evidence against the de novo conformational coupling hypothesis. Cell Calcium 42, 606-617.

Redondo PC, Harper AGS, Sage SO & Rosado JA. (2007). Dual role of tubulin-cytoskeleton in Store-operated calcium entry in human platelets Cell Signalling 19, 2147-2154.

Redondo PC, Harper AGS, Harper MT, Brownlow SL, Rosado JA & Sage SO. (2007). hTRPC1-associated alpha-actinin, and not hTRPC1 itself, is tyrosine phosphorylated during human platelet activation. Journal of Thrombosis and Haemostasis 5, 2476-2483.


Redondo PC, Harper MT, Rosado JA & Sage SO. (2006). A role for cofilin in the activation of store-operated calcium entry by de novo conformational coupling in human platelets. Blood 107, 973-979.

Harper MT & Sage SO. (2006). Actin polymerisation regulates thrombin-evoked Ca2+ signalling after activation of PAR-4 but not PAR-1 in human platelets. Platelets 17, 134-142.

Cauwenberghs S, Feijge MA, Harper AGS, Sage SO, Curvers J & Heemskerk JWM. (2006). Shedding of procoagulant microparticles from unstimulated platelets by integrin-mediated destabilization of actin cytoskeleton. FEBS Letters 580, 5313-5320.

Harper MT & Sage SO. (2006). PAR-1–dependent pp60src activation is dependent on protein kinase C and increased [Ca2+]i: evidence that pp60src does not regulate PAR-1–dependent Ca2+ entry in human platelets. Journal of Thrombosis and Haemostasis 4, 2695-2703.


Rosado JA, Redondo PC, Salido GM, Sage SO & Pariente JA (2005). Cleavage of SNAP-25 and VAMP-2 impairs store-operated Ca2+ entry in mouse pancreatic acinar cells. American Journal of Physiology 288, C214-C221.

Brownlow SL & Sage SO. (2005). Transient receptor potential protein subunit assembly and membrane distribution in human platelets. Thrombosis and Haemostasis 94, 839-845.

Rosado JA, Redondo PC, Sage SO, Pariente JA & Salido GM. (2005). Store-operated Ca2+ entry: Vesicle fusion or reversible trafficking and de novo conformational coupling? Journal of Cell Physiology 205, 206-209.


Brownlow SL, Harper AGS, Harper MT & Sage SO. (2004). A role for hTRPC1 and lipid raft domains in store-mediated calcium entry in human platelets. Cell Calcium 35, 107-113.

Rosado JA, Redondo PC, Salido GM, Gomez-Arteta E, Sage SO & Pariente JA. (2004). Hydrogen peroxide generation induces pp60src activation in human platelets. Evidence for the involvement of this pathway in store-mediated calcium entry. Journal of Biological Chemistry 279, 1665-1675.

Redondo PC, Harper AGS, Salido GM, Pariente JA, Sage SO and Rosado JA. (2004). A role for SNAP-25 but not VAMP in store-mediated Ca2+ entry in human platelets. Journal of Physiology 558, 99-109.

Rosado JA, Lopez JJ, Harper AGS, Harper MT, Redondo PC, Pariente JA, Sage SO and Salido GM. (2004). Two pathways for store-mediated calcium entry differentially dependent on the actin cytoskeleton in human platelets. Journal of Biological Chemistry 279, 29231-29235.


Brownlow SL & Sage SO. (2003). Rapid agonist-evoked coupling of the type II inositol 1,4,5-trisphosphate receptor to human transient receptor potential (hTRPC1) channels in human platelets. Biochemical Journal 375, 697-704.