In
1952, Rollo was appointed Chairman of the Physiology Department, Vanderbilt
University Medical School. During his first year, the department was
sparsely populated, with Robin Post and Ray Meng as Assistant Professors.
Rollo immediately began strengthening the research program by supporting and
redirecting the efforts of the existing staff and by attracting outstanding
new faculty such as Janey Park and Howard Morgan. In collaboration with
Howard Morgan, Robin Post, David Regen, and others, Rollo carried out
classic experiments on the effects of insulin, growth hormone and
glucocorticoids on glucose transport and phosphorylation in perfused rat
hearts. In particular, it was shown that the transfer of glucose across the
muscle plasma membrane occurred by facilitated diffusion and was a major
site of action of insulin and anoxia. Muscle from diabetic animals was found
to exhibit inhibition of both glucose transport and phosphorylation which
was attributable to indirect actions of growth hormone and adrenal
glucorticoids.
A
landmark in the history of the Physiology Department came in 1963 when Rollo
recruited Earl Sutherland, who in 1971 won the Nobel Prize in Physiology or
Medicine for his discovery of cyclic AMP. Earl Sutherland brought and
attracted many young associates such as R.W. Butcher, G.A. Robinson, Joel
Hardman, Roger Johnson, David Garbers and Arthur Broadus. Soon there began
an era of very fruitful collaboration between this "cyclic AMP group" and
other members of the Department including John Exton, J.G.T. Sneyd, Jackie
Corbin, L.S. Jefferson, Ren Jye Ho and Stephen Lewis. During this period,
the roles of cyclic AMP in the lipolytic action of catecholamines in adipose
tissue and in the gluconeogenic action of glucagon in liver were defined,
and insulin was shown to antagonize the actions of catecholamines and
glucagon by reducing cAMP accumulation in these tissues.
Beginning in 1964 in collaboration with John Exton, and later with Larry
Mallette, Michio Ui, Tom Claus, Tim Chan, Naomi Friedmann and Tom Miller,
Rollo undertook a series of studies on the regulation of hepatic
gluconeogenesis. These defined the role of substrates, glucagon,
catecholamines, insulin and glucocorticoids in the control of this process
and identified the sequence of reactions between pyruvate and P-enolpyruvate
as a major site of hormonal control.
Beginning in 1970 with the return of Jackie Corbin and the arrival of Tom
Soderling, Simon Pilkis and Alan Cherrington, Rollo initiated a new series
of physiological investigations focused around cyclic AMP-dependent protein
kinase, the newly discovered enzyme mediator of cyclic AMP action in
eukaryotic cells. These researches defined the role of enzyme
phosphorylation in the regulation of lipolysis in adipose tissue by
catecholamines and insulin and in the control of glycogenolysis and
gluconeogenesis in liver by catecholamines and glucagon. With Rollo's advice
and encouragement, Jackie Corbin initiated his studies of the mechanisms
involved in the activation of cyclic AMP-dependent protein kinase, Tom
Soderling explored the regulation of glycogen synthase by
phosphoryiation-dephosphorylation mechanisms, Simon Pilkis studied
the roles of pyruvate kinase, fructose bisphosphatase and
phosohofructokinase in the regulation of gluconeogenesis, and Alan
Cherrington defined the interactions between glucagon, insulin and glucose
in the regulation of hepatic glucose production and gluconeogenesis in
vivo. These young investigators rapidly became recognized leaders in
their research areas.
During the 1970s, again with Rollo's encouragement and valued counsel, the
work of Tetsuro Kono on the mechanisms involved in insulin action on glucose
transport and lipolysis in adipose tissue came to brilliant fruition, Robin
Post continued his salient studies on(Na+,K+)ATPase, and Ray Meng's work led
to his recognition as an authority on parenteral nutrition. Rollo also
directed the investigations of David Loten and Stanley Keely at this time.
Most
recently, Rollo has begun an extensive collaboration with Janey Park and
others on the analysis of biological processes utilizing electron
paramagnetic resonance spectroscopy. The work of this group has resulted in
the development of new, high resolution spin probes which have been used to
explore a variety of problems such as. coenzyme binding to dehydrogenases,
fatty acid binding to albumin, and membrane structure-function
relationships. As an extension of this effort, Rollo and his associates have
shown that fatty acids enter adipocytes by a transport system which is
stimulated by insulin. These recent studies continue to demonstrate the
freshness and ingenuity so characteristic of Rollo's experimentation.
Through his firm commitment to excellence in research and his extraordinary
ability to foster the development of the careers of young scientists and
students, Rollo has built the Physiology Department into an internationally
respected center for studies of hormone action, membrane transport, and
metabolic regulation. Many associates have been appointed to Chairmanships
or Professorships of basic medical science departments at other
institutions, and have continued to espouse Rollo's high standards in
scientific research. The research strengths of the department facilitated
the establishment of the first Diabetes and Endocrinology Research Center at
Vanderbilt in 1973 and have contributed greatly to the worldwide reputation
of Vanderbilt Medical School.
Of
particular importance to Vanderbilt University has been Rollo's twenty year
association with the Howard Hughes Medical Institute. As a member of the
Advisory Board he played a major role in determining the direction of the
scientific program of the Institute, and in establishing the Institute
Laboratories at Vanderbilt. Among the many local and national organizations
in which Rollo has participated are the American Physiological Society, the
American Society of Biological Chemists, the Association of American
Physicians and the American Society of Clinical Investigation, in which
organization he served as Vice-President in 1961. For twelve years he was
member, and finally Chairman, of the Life Insurance Medical Research Fund.
He was also Chairman of the Advisory Board of Juvenile Diabetes Foundation
and Counsellor of the National Heart Institute. Currently, he serves as a
member of the Advisory Board of the International Institute of Cellular and
Molecular Pathology in Brussels.
In
1968 Rollo was honored at Vanderbilt by being awarded the Harvie Branscomb
Distinguished Professorship. In 1978 he received the Banting Medal of the
American Diabetes Association, its highest honor, and in 1980 he was elected
to the National Academy of Sciences.
In
these and numerous other ways, Dr. Park has consistently brought honor to
Vanderbilt University by advancing the cause of excellence in education,
science and medicine.
From the Introduction to A Symposium on Metabolic Regulation in
honor of Dr. Charles R. Park held Friday, October 9, 1981, Vanderbilt
University School of Medicine, Nashville, Tennessee