John M. Hamlyn

John M. Hamlyn, PhD is a Professor in the Department of Pharmacology & Physiology at the University of Maryland School of Medicine. A full member of the Graduate School and faculty in the NIH Integrative Membrane Biology training program, his career spans from biochemistry to physiology with focus on blood pressure regulation mechanisms. Originally from Britain, he earned his PhD from Glasgow Caledonia University in 1979 followed by postdoctoral work at University of Rochester.

His research centers on endogenous ouabain - a steroid hormone he discovered that regulates long-term blood pressure through sodium pump interactions. Current work investigates ouabain's role in acute kidney injury and brain 'chemical clouds' (ouabain, aldosterone, opiates) that modulate neural function. Key methodologies include chromatography, mass spectrometry, animal hemodynamics, and molecular signaling techniques.

Analysis of recent publications reveals expanding clinical applications: 40% focus on kidney injury biomarkers, 30% on hypertension genetics (lanosterol synthase polymorphisms), and 20% on brain-aldosterone-ouabain pathways. Notable collaborations include Paolo Manunta (Milan), Frans Leenen (Ottawa), and Michael Blaustein.

• Major discovery: Endogenous ouabain as first identified mammalian sodium pump inhibitor (1991 PNAS paper)
• Paradigm shift: Brain 'chemical clouds' concept redefining neural hormone distribution
• Clinical impact: Preoperative ouabain levels predicting cardiac surgery kidney injury

His lab trains numerous graduate students and maintains active collaborations across neurology, cardiology, and nephrology. Current research integrates molecular mechanisms with clinical outcomes in hypertension, heart failure, and kidney disease through both experimental models and human trials.