ABSTRACT
Clopidogrel and ticagrelor, antagonists to P2Y(12) receptor molecules on platelet membranes, significantly ameliorate acute myocardial infarction due to coronary artery thrombosis, the most common cause of death in the developed world. A personal account is given here of the foundational research that lead to the identification of P2Y receptors, carried out 50 years ago in the Melbourne University Zoology Department headed by Geoffrey Burnstock. In Christmas 1962, I made the serendipitous observation of large hyperpolarizing changes across the membranes of smooth muscle cells in the taenia coli of the intestine on stimulating its nerve supply. I then showed that these potentials relaxed the muscle and were not due to noradrenaline or acetylcholine, which were then the only substances known to be released from nerves. I called these non-adrenergic, non-cholinergic (NANC) terminals in the laboratory and showed that this NANC transmitter acted at receptor molecules on the muscle cells, promoting efflux of potassium ions, and so the observed potential changes. In 1968, Graeme Campbell showed that ATP relaxed the taenia coli muscle, and in 1969, David Satchell, using purine chromatography, showed that ATP was likely to be released from NANC terminals. The receptor molecules involved were shown to be exceptionally sensitive to 2-methylthio-ATP (Satchell and Macguire, 1975, J Pharmacol Exp Ther, 195, 540), and so belonged to the class P2Y receptors as designated by Abbracchio and Burnstock, with subclasses P2Y(1)-P2Y(12). The discovery of the role of P2Y(12) receptors in increasing thrombosis lead to the focused research that resulted in clopidogrel and ticagrelor.
Subject(s)
Coronary Artery Disease/metabolism , Coronary Thrombosis/metabolism , Muscle, Smooth/metabolism , Receptors, Purinergic P2Y/history , Receptors, Purinergic P2Y/metabolism , Adenosine/analogs & derivatives , Adenosine/history , Animals , Clopidogrel , Coronary Artery Disease/drug therapy , Coronary Thrombosis/drug therapy , History, 20th Century , Humans , Purinergic P2Y Receptor Antagonists/history , Ticagrelor , Ticlopidine/analogs & derivatives , Ticlopidine/historyABSTRACT
Cladribine is effective therapy for HCL, and there are several ways to achieve the adequate concentrations of the active metabolites in relevant cells, without the need for long-term continuous infusions. This simplifies therapy, although careful control of patients is required during and after treatment in most instances because of the significant activity of the drug on leukemia cells of various types and also on lymphoid cells and normal stem cells.
Subject(s)
Adenosine/analogs & derivatives , Adenosine/pharmacokinetics , Antimetabolites, Antineoplastic/pharmacokinetics , Leukemia, Hairy Cell/drug therapy , Adenosine/history , Adenosine/therapeutic use , Adenosine Deaminase/metabolism , Adenosine Deaminase Inhibitors , Antimetabolites, Antineoplastic/history , Antimetabolites, Antineoplastic/therapeutic use , Apoptosis/drug effects , Deoxycytidine Kinase/antagonists & inhibitors , Deoxycytidine Kinase/metabolism , History, 20th Century , History, 21st Century , Humans , Leukemia, Hairy Cell/enzymology , Leukemia, Hairy Cell/history , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/metabolismABSTRACT
In a remarkable career, straddling five decades, John Phillis pursued with fierce determination and exceptional energy the main goal of his scientific life, to throw light on the chemical agents that control brain function. Starting in Australia, he settled in North America, first in Canada, then in the USA, where his long tenure at Wayne State brought his career to its culmination.
