Physiologist

Born: November 22, 1936;

Died: August 13, 2016

DOCTOR Tom Forrester, who has died aged 79, was a physiologist whose work brought a new understanding to what happens to blood that flows through muscle when we exercise.

He was born and educated in Glasgow where he qualified in medicine. After a year in hospital posts he joined the Institute of Physiology of Glasgow University. At the time, the 1960s, there was continuing interest in neuro transmitters, the small molecules which allow nerve cells to send signals to other nerves or to the many end organs such as muscles which they are controlling.

Professor Sir Bernard Katz, a biophysicist and Nobel Prize Winner in neuro transmitter function had suggested a project to Glasgow physiologist professor Iain Boyd. Dr Forrester was given this project as the subject for his PhD work. It proved interesting but not in a way that was expected.

The aim was to measure the neuro transmitter released when muscle was stimulated. However, despite considerable effort, the experiment could not be made to work. Worse than that, the detection system used, a humanely isolated beating frog heart, reacted in an unexpected way. Instead of being inhibited by the fluid coming from the contracting muscle it was stimulated to beat faster and stronger. Something coming from the contracting muscle was interfering and stimulating the frog heart. What was it?

Dr Forrester learned a series of biochemical techniques to try to resolve the problem. He was told by a senior professor that it could take a team of five scientists ten years to identify the interfering substance. Dr Forrester carried on with the optimism of youth.

The uncertainty ended with the use of firefly extract to show that the interfering substance produced a glow of light in the presence of the firefly material. The energy source for a firefly and the interfering substance released from active muscle proved to be the energy transporter molecule found within all living cells, ATP, Adenosine Triphosphate. Dr Forrester proceeded to show that ATP is released from human muscles as they contract and has positive effects on blood flow in exercise.

Dr Forrester accepted a position as associate professor in physiology in the University of St Louis and moved there with his family in 1975. He remained professor in the department for 30 years. He graduated MD with honours from Glasgow on the basis of his extensive published work. The family became US citizens but Dr Forrester kept hold of his Scottish roots with regular visits to Scotland and as very successful president of the St Louis St Andrews Society.

Dr Forrester was a very engaging character and always had a story to relate, often about something amusing that had happened to him, told with a twinkle in the eye. A fine recreational golfer, he had a lively mind and found much to interest him in family, science and the world about him.

It is well established that exercise has many favourable effects on human health. As the complexities of ATP release and uptake by many cell types are progressively worked out, Dr Forrester’s ground breaking discovery deserves to be remembered.

He is survived by his wife Norma, three children, and six grandchildren. He has two sisters living in Scotland.

ALASTAIR GLEN