Career Information

Physiology is the study of "how the body works". A key concept in physiology is "homeostasis", which is a term used to describe how all the body processes work together to provide normal function, and to adapt to external (e.g. temperature, oxygen levels) and internal (e.g. disease) challenges to our body systems. Studies cover the whole spectrum of the living organism, ranging from experiments involving molecular biology to measurements made in whole animals or human subjects. Ongoing research provides new information about male and female reproductive systems, the process of birth, and the physiology of the fetus and newborn. Studies in neurophysiology attempt to unravel mysteries of the brain with respect to control of eye and limb movements and the neural control of the circulation. Cardiovascular research includes the study of normal and abnormal heart rhythms, mechanisms of contraction of the heart, age-related changes in heart function, and the influence of the kidney in control of blood pressure. Studies in cellular physiology examine how the stomach is protected from its own acid, how nerve and muscle cells communicate with each other, how bone cells make and breakdown bone, and how various hormones are produced, secreted, and involved in controlling cell function. Physiology provides the basic information for understanding the normal function of the body, explains how normal function may be altered in pathological conditions, and provides insight for developing strategies to manage and treat various diseases and conditions.

Why study physiology? Students take physiology for several reasons. First, it is a core subject in all health-related disciplines (e.g. medicine, dentistry, nursing, kinesiology, physiotherapy, etc.). Students take physiology as a background or prerequisite for these disciplines. Second, students wishing to do graduate studies in any of the health sciences disciplines find physiology to be a valuable background for providing an overall perspective on how the body works. Third, students tell us they take physiology because it is interesting and consequently they are motivated to do well at it!

Pharmacology is the study of drug actions on biological systems. It embraces knowledge of the sources, chemical properties, biological effects and therapeutic uses of drugs.

Historically, the roots of pharmacology go back to the ancient civilizations which used plants and plant extracts both in healing and as poisons. The accumulated total of this empirical knowledge, acquired by mankind through the ages, provided a foundation for the evolution of scientific pharmacology as it exists today. The well known discovery of the beneficial effects of foxglove extracts for treating some kinds of heart disease, the use of the bark of the willow and cinchona trees in treating fever and the effectiveness of extracts of the poppy in the treatment of dysenteries are outstanding examples of such knowledge which have resulted in important advances in pharmacology, developments which continue today. The rise of organic chemistry in the last half of the nineteenth century, together with the development of physiology and, later, biochemistry, allowed empiricism to be discarded in favour of a rational approach which today underpins the discipline of pharmacology.

Pharmacology is truly multidisciplinary in scope. Research in this field is closely interwoven with the subject matter and experimental techniques of analytical chemistry, biochemistry, cellular and molecular biology, genetics, immunology, medicinal chemistry, microbiology, pathology, and physiology. Consequently, there are a number of distinct sub-disciplines of pharmacology that one may develop a career in.

Integrating a depth of knowledge in many related scientific disciplines, pharmacologists offer a unique perspective to solving drug-, hormone-, and chemical-related problems which impinge on human health. As they unlock the mysteries of drug actions, discover new therapies, and develop new medicinal products, they inevitably touch upon all our lives.

While remarkable progress has been made in developing new drugs and in understanding how they act, the challenges that remain are endless. New discoveries regarding fundamental life processes always raise new and intriguing questions that stimulate further research and evoke the need for fresh insight.

Some components of pharmacology include:

• Study of how drugs work at the cellular and molecular level.
• The use of drugs as tools to dissect aspects of cell function.
• Development of new synthetic drugs to improve on existing drugs or to treat new human conditions which will respond to drug treatment. This includes computer assisted molecular modeling of drug structures, leading to the development of better drugs with fewer side effects ("designer drugs").
• Formulation of clinical guidelines for the safe and effective use of drugs.

Fields of Study in Pharmacology

Biochemical Pharmacology: Biochemical pharmacology uses the methods of biochemistry, cell biology and cell physiology to determine how drugs interact with, and influence, the chemical "machinery" of the organism. The biochemical pharmacologist uses drugs as probes to discover new information about biosynthetic pathways and their kinetics, and investigates how drugs can correct the biochemical abnormalities that are responsible for human illness.

Molecular Pharmacology: Molecular pharmacology deals with the biochemical and biophysical characteristics of interactions between drug molecules and those of the cell. It is molecular biology applied to pharmacologic and toxicologic questions. The methods of molecular pharmacology include precise mathematical, physical, chemical or molecular biological techniques to understand how cells respond to hormones or pharmacological agents, and how chemical structure correlates with biological activity.

Cardiovascular Pharmacology: Heart disease is one of the leading causes of premature death in western societies. Cardiovascular pharmacology concerns the effects of drugs on the heart, the vascular system, and those parts of the nervous and endocrine systems that participate in regulating cardiovascular function. Researchers observe the effects of drugs on arterial pressure, blood flow in specific vascular beds, release of physiological and pathobiological mediators, and on neural activity arising from central nervous system structures.

Neuropharmacology: The study of drugs that modify the functions of the nervous system, including the brain, spinal cord, and the nerves that communicate with all parts of the body. Neuropharmacologists study drug actions from a number of different viewpoints. They may probe the neurochemical disorders underlying specific disease states (eg Alzheimer's and Parkinson's disease) to find new ways to use drugs in the treatment of disease. Alternatively, they may study drugs already in use to determine more precisely the neurophysiological or neurobiochemical changes that they produce. Other studies use drugs as tools to elucidate basic mechanisms of brain function, or to provide clues to the nature of disease processes.

Chemotherapy: The study of drugs used to combat infection (bacteria, viruses and parasites) as well as malignancies (cancer). Pharmacologists working in this area focus on the biochemistry of both the host and the infecting organism in order to define mechanisms capable of exploitation by drugs. The ideal chemotherapeutic drugs will selectively inhibit the growth of, or kill, the infectious agent or cancer cell without seriously impairing the normal functions of the host.

Pharmacokinetics: The study of the absorption, biodistribution, and elimination of drugs and chemicals from the body. The pharmacokinetics of a drug must be understood before the full extent of its actions can be determined. This is especially important in establishing the correct clinical dosage of a drug.

Immunopharmacology: Immunopharmacology deals with the selective chemical control of the immune response in the treatment and prevention of disease. Research in this area includes work on immunosuppressant agents used in organ transplant operations, as well as the development of agents to enhance the immune response as required for the treatment of diseases such as AIDS.

Clinical Pharmacology: The use of drugs in treating disease in humans. This area encompasses the therapeutic management of disease by drugs, as well as the final stages of development of new drugs or new uses for existing drugs. Clinical pharmacologists study how drugs work, how they interact with other drugs, how their effects can alter the disease process, and how disease can alter their effects.

Behavioural Pharmacology: Study of the effects of drugs on behaviour. Research includes topics such as the effects of psychoactive drugs on the phenomena of learning, memory, wakefulness, sleep and drug addiction, and the behavioural consequences of experimental intervention in enzyme activity and brain neurotransmitter levels and metabolism.

Examples of Questions Asked By Pharmacologists

• What tissue receptors (i.e. specific protein molecules) do drugs interact with to produce their effects, and how are these receptors linked to biological responses?
• What points in biochemical pathways are rate-limiting and thus potential sites at which drugs act to alter the pathways?
• How do drugs act on cell surfaces to alter processes inside cells?
• How can drugs be used as selective probes to unravel details of biochemical and physiological processes?
• What changes in the brain are responsible for schizophrenia and depression, and what agents will be most effective in treating these conditions?
• How can knowledge of the structure of a macromolecule be used to design new chemical agents that will bind to and change the activity of the macromolecule?
• How do organisms, organs and individual cells develop increased or decreased sensitivity to drugs?
• How are drugs cleared from the body?
• Why are some individuals hypersensitive to the side-effects of drugs?
• How do drugs get into cells to exert their therapeutic effects?

*NOTE: Pharmacology is different from Pharmacy.

Pharmacology versus Pharmacy

Do not confuse pharmacology with pharmacy. They are separate disciplines!
Pharmacy is the profession responsible for the preparation, dispensing, and appropriate use of medication, and provides services to achieve optimal therapeutic outcomes.
Pharmacology is a research discipline that is focused on defining the mechanisms of action of drugs and the biological systems upon which they act.

The University of Western Ontario DOES NOT offer a degree in Pharmacy.

If you are interested in studying Pharmacy, please take a look at the programs offered at the following Canadian Universities:

• Memorial University of Newfoundland
• Dalhousie University
• University of Montreal
• Laval University
• University of Toronto
• University of Manitoba
• University of Saskatchewan
• University of Alberta
• University of British Columbia

Centuries ago, Paraceulsus (1493-1541) one of the founding fathers of toxicology, noted, "All things are poisons, for there is nothing without poisonous qualities. It is only the dose which makes a thing a poison." Therefore, toxicology is defined as the study of the adverse (toxic) effects of both chemical and physical agents on biological systems. Toxicology is considered both an art and science; the science involves the data-gathering phase while the art of toxicology uses this acquired data to predict the likelihood of adverse responses in humans and wildlife following exposure to one or more agents in situations where there is limited information. For example, the observation that exposure to chloroform can produce hepatomas in mice is a documented fact while the conclusion that it will do so in man is a prediction or hypothesis.

There are two classes of agents that toxicologists study:

• Chemical agents (synthetic or naturally-occurring) that include 64,000 compounds used in commerce (5,000 million tons per year or more); 5,000 food additives; 4,000 medicinal drugs; 1,200 household products (at least!); substances produced by bacteria, fungi, molds, spores, plants and animals and approximately 700 new chemicals that are identified or introduced each year.
• Physical agents such as radiation (e.g. UV, electromagnetic), noise, pressure and dust.

Fields of Study in Toxicology

It is difficult classify a toxicologist with any one particular field of toxicology since many of the problems require an integrative approach to problem solving. Therefore, most toxicologists use a variety of approaches that span several of these areas to obtain a comprehensive picture of the risks associated with the substance under investigation. These fields include:

Biochemical Toxicology: Biochemical toxicology uses the methods of biochemistry, cell biology and cell physiology to determine how toxic substances adversely affect the normal functioning of cellular components. Biochemical toxicologists investigate the enzymes responsible for the metabolism of a specific compound or how a substance inhibits an enzyme activity, which is essential for normal cell function.

Molecular Toxicology: Molecular toxicology involves the use of molecular biology to investigate the effect of toxic substances at the level of DNA. Molecular biology techniques have been used to examine the effects on compounds on gene regulation and DNA mutagenesis. These methodologies have also been used to investigate the role of proteins in drug metabolism and to identify specific domains, which are essential enzyme activity.

Chemical Carcinogenesis: Chemical carcinogenesis investigates how compounds initiate and promote the development of cancer. These studies include identifying the enzymes responsible for activating the compound to a carcinogen as well as the genes that are mutated by the compound. A few compounds that have been investigated include chemotherapeutic drugs, polycyclic aromatic hydrocarbons, aromatic amines, halogenated hydrocarbons and mycotoxins.

Environmental Toxicology: Environmental toxicology examines the effect of substances that are present in the environment. This includes investigating the effects of all types of pollution resulting from compounds that have been released into the environment following their use or that have been introduced as unwanted by-products or decomposition products. In addition to examining the effects of these compounds on mammalian species, environmental toxicologists also examine effect of these substances on birds, fish, reptiles and plants.

Genetic Toxicology: Genetic toxicology is the study of the interaction of chemical and physical agents with the process of heredity. These studies involve investigating the type of mutations that an agent causes and its effects on chromosomes. In addition, genetic toxicologists develop assays to identify genotoxic substances that may adversely affect human health and environmental quality.

Developmental Toxicology: Developmental is concerned with the investigation of chemically induced teratogenic effects or birth defects. Studies involve examining any detrimental effect produced following exposure of a developing organism during development. Currently, developmental biology is one of the most exciting fields of study which will facilitate a better understanding of how toxic substances perturb the complex regulation patterns required for normal development.

Immunotoxicology: The field of immunotoxicology examines the effect of substances on the immune system. Studies involve examining the ability of chemicals to compromise immune function, elicit hypersensitive reactions and induce autoimmunity.

Reproductive Toxicology: The survival of any species is dependent on the integrity of its reproductive system. Therefore, the effects of drugs and environmental chemicals on reproductive fitness are a major health concern. Reproductive toxicologists examine how toxic substances affect reproductive capacity and develop assays to identify agents that may adversely affect reproductive performance.

In addition to these fields of study, there are several other areas of toxicology that have not been listed including regulatory toxicology (risk assessment/risk management), forensic toxicology, clinical toxicology, veterinary toxicology and occupational toxicology.

Examples of Questions Asked By Toxicologists

• What are the fates of chemicals in biological systems and in the environment?
• What are the biochemical or molecular mechanisms responsible for the effects of toxic substances on various cells and organs?
• How do environmental chemicals cause cancer?
• How can scientists best determine the chemical structure of a newly found toxic substance?
• How can physicians treat persons who become ill by exposure to agents in food or the environment?
• How can industrial chemists design safe chemical products (e.g. pesticides and drugs)?
• What guidelines should be used for establishing acceptable levels of chemical exposure in air, water and food?
• Do pesticides residues present in food cause cancer in humans?
• Is it safe to eat fish caught in the Great Lakes?
• Are there better ways of identifying a substance that may adversely affect human health and environmental quality?
• Why do some people experience adverse reactions to certain drugs?
• How does dioxin cause its toxic effects?
• Can increases in breast cancer incidence be attributed to carcinogenic compounds present in the environment?
• What is "Mad Hatter's" disease?
• How does an organism protect itself from toxic substances?

Biological Research: Physiologists, Pharmacologists and Toxicologists perform experiments to determine the way drugs interact with various living systems, and to define the mechanism involved in producing those interactions. Some of this work is carried out using experimental animals such as rats and mice. Usually organs, tissues or cells derived from such animals are used although some studies are done with humans. Some of this experimental work is directed at exploring the way a chemical compound causes its biological effect and in defining the way related compounds behave. Other work involves using the known effects of drugs and chemicals to help in determining the physiological, biochemical or immunological function of various tissues and organs under normal or pathological conditions. Some pharmacologists and toxicologists function independently while others are part of multi-disciplinary teams which may include synthetic chemists, cell and molecular biologists, and experts in other related disciplines. Most of this type of experimental work is carried out in universities or research institutes. Those pharmacologists and toxicologists who work in universities are usually also involved in teaching aspects of pharmacology to undergraduate students as well as to medical, dental, pharmacy, nursing and graduate students.

Industrial Research: Some pharmacologists and toxicologists work in the pharmaceutical industry. Much of the research carried out in industry is similar to that referred to above with the additional goal of discovering therapeutically useful molecules that are safe. It is more usual for research pharmacologists and toxicologists in industry to function as part of multi-disciplinary teams, which focus on a particular disease or organ system. Additional work involves measurement of the biological activity of drug preparations in order to ensure effectiveness and the standardization of such measurements. Screening the activities of families of chemical compounds for biological activity in various systems is also an important aspect of the industrial pharmacologist's work, and characterizing the toxicological properties of candidate drugs is the work of industrial toxicologists.

Human Pharmacology: Pharmacologists who study the therapeutic and toxic actions of drugs in humans are referred to as clinical pharmacologists. These individuals are usually, although not always, physicians who have specialized training in the use of drugs and combinations of drugs in the treatment of disease processes. Clinical pharmacologists are also concerned with the correct routes of administration of drugs, with assessing their side-effects, with monitoring their levels in patients and with preventing or treating overdoses as well as the consequences of interactions with other drugs. Clinical pharmacologists are also involved in the final stages of new drug development in which trials are carried out in patients and normal volunteers. The necessity of working with patients makes the possession of a medical qualification necessary. Non-medically trained clinical pharmacologists work in collaboration with clinically trained colleagues in hospitals and pharmaceutical companies and perform necessary laboratory work as well as organizing clinical trials of new drugs.

Regulation: Some pharmacologists and toxicologists are involved in the administration of the body of laws and regulations relating to the development and use of drugs. They may work in the pharmaceutical industry to ensure that all necessary steps are followed in the testing of a new drug prior to its use in humans. Alternatively, they may work for government (mostly federal) to help examine the new drug submissions of pharmaceutical companies for compliance with the regulations. Pharmacologists and toxicologists also serve as consultants and expert witnesses.

The usual route to a career in physiology, pharmacology and/or toxicology involves obtaining both an undergraduate and a graduate degree.

The undergraduate degree is often an Honors Bachelor of Science degree (B.Sc. Hons.) or Honors Bachelor of Medical Sciences degree (B.MSc. Hons.) in a relevant area such as pharmacology, toxicology, physiology, biology, biochemistry, chemistry, microbiology, molecular biology, or zoology. This degree takes four years.

The graduate degree is usually a doctorate (Doctor of Philosophy, Ph.D.) obtained through advanced studies in one of the biological sciences indicated above. This degree normally takes about five years to obtain after completing the Hons. B.Sc. degree. The degree of Master of Science (M.Sc.), which takes about two years to obtain after the Hons. B.Sc., may also be used in preparation for a career in pharmacology/toxicology, but the holder of an M.Sc. degree is usually more limited in the choice of positions available. In general, holders of a Ph.D. degree work in positions where they direct a research laboratory and undertake independent research. Holders of a M.Sc. degree, on the other hand, usually work as research assistants/associates in laboratories and undertake research projects under the direction of a senior scientist.

Another route involves obtaining the degree of Doctor of Medicine (MD). Holders of this degree usually also study further, either pursuing a fellowship in medicine or clinical pharmacology in order to function as a clinical pharmacologist, or performing research and obtaining the PhD degree. Some schools (including the University of Western Ontario) offer joint MD/PhD programs which allow both degrees to be obtained in six years rather than the normal time of eight years if pursued separately (four years for each degree). More information on the MD-PhD concurrent degree program can be obtained from the program director Dr Chris Brandl, cbrandl@uwo.ca 

If you are currently in high school: you should plan on completing the requirements for admission to the first year of a university science or biology program. These should include biology, physics, chemistry and mathematics. It is also important to study English as the ability to communicate using both verbal and written language is an essential skill of the modern scientist. Visit the Office of the Registrar website for more information on admission requirements and procedures.

If you are already in university: plan on completing an honors degree (B.Sc.) in a biological science such as pharmacology, pharmacy, toxicology, physiology, chemistry, biochemistry, or zoology (among others), before applying to a department of physiology, pharmacology and/or toxicology for admission to its graduate program. Admission to these programs is always competitive.

• Experimental Medicine Job Listing (EMJL)
• FASEB Career Resources
• Science's Next Wave
• NSERC Concourse
• Medicines by Design: The Biological Revolution in Pharmacology (From the National Institute of General Medical Sciences (NIGMS))
• Quebec Directory of Public Research (This directory lists scientific investigators in all fields working within Québec's public sector. Internationally, this site promote communication among researchers, industry and knowledge partners)