Practical Pharmacology for the Pharmaceutical Sciences

D. Michael Salmon

• Publisher: Wiley
• Year: 2013
• ISBN:
  9781118696569
• Edition: 1
• Topic: Medizin
• Subtopic: Pharmakologie

Practical Pharmacology for the Pharmaceutical Sciences is a lab survival guide for those studying Pharmacology, providing hands-on advice on developing pharmacology laboratory and data handling skills. Suitable for both undergraduates and postgraduates, it focuses on laboratory techniques rather than computer-simulated data. It also guides the reader through the process of communicating experimental results in a variety of formats, including posters, oral presentations and project reports.

Split into three main areas, the following topics are covered in detail:

Preparation for Experimental Pharmacology

• Legal aspects
• Fundamentals of Pharmacology
• Definitions, calculations and statistics

Experiments in Pharmacology

• Microtitre-based techniques using isolated cells
• In vitro techniques using isolated tissues and organs
• Biochemical techniques using cell-free systems

Communicating experimental results

• Data presentation
• How to write scientific reports
• Pharmacological literature

Supported with numerous questions throughout the text, as well as step by step instructions for practical experiments, this book presents an approach to learning pharmacology through an appreciation of authentic experimental data.

1

Before Entering the Pharmacology Laboratory

Before embarking on any new activity, it is wise to be familiar with the language, concepts and possible risks of the venture. So this book begins with a number of topics with which an experimenter must be familiar, such as health and safety, ethical and legal considerations and fundamental principles of experimental pharmacology. No experiment has much value unless a coherent design has been devised first. The design of an experiment is crucial if it is to yield meaningful results. Having obtained the experimental data, it is important to decide on the relevant statistical methods that will be employed to evaluate the results. Obvious as this may seem, it is shocking, even in professional research, how many experiments are wasted due to a lack of planning in design.

1.1 SAFETY AND RISK ASSESSMENT

All activities which involve the use of chemicals, from the factory floor to the research laboratory, are subject to the Health and Safety legislation. In the United Kingdom, this is done by the Health and Safety Executive (HSE), and of particular relevance in the laboratory is the Control of Substances Hazardous to Health Regulations (COSSH, 2002). In the United States, the body is the Occupational Safety and Health Administration (OSHA), who require a Chemical Hygiene Plan (CHP) for each experiment, whilst in the EC the relevant body is the European Agency for Safety and Health at Work (EU-OSHA).

In the United Kingdom, COSSH regulations apply to all places of work, and all workers must be conversant with all risks and safety procedures. A risk assessment of all procedures must be carried out and a documentation of how these risks are to be minimized during the procedure and safe procedures for disposal of chemicals must be displayed. Any accidents must be reported and logged for future reference.

The bioscience laboratory presents many hazards not encountered elsewhere, and COSSH regulations are especially important. All laboratory workers must be aware of the regulations governing all work in laboratories. Drinking, eating and smoking are banned in all laboratories. No chemicals should come into contact with the body – including the mouth, eyes and skin whilst inside a laboratory. Remember that in a pharmacology laboratory, there is exposure to many highly biologically potent chemicals. A protective coat (frequently white) must be worn at all times, and protective eye goggles and gloves worn when required. In addition, laboratory workers must be familiar with the international warning symbols for toxic, corrosive and inflammable chemicals and gases, cancer-causing and suspected cancer-causing chemicals, radioactive materials, biological hazards, and reproductive hazards. These are widely available and explained on the internet. If a student is unsure of the meaning of any symbols they should ask their supervisor. These are not only displayed at the entrance to laboratories, but also on individual chemicals and equipment.

For class laboratory exercises, it is the responsibility of the supervisor to identify all risks and display them in the laboratory. This is not just a piece of administration, but an important document all students must be familiar with before they start the experiment to ensure safe practice. Students must be familiar with all the chemicals to be used and if there are any special precautions that must be taken. Before a project is undertaken, a risk assessment must be carried out by the student with appropriate guidance. The information that must be sought is given as follows.

• What are the dangers of handling individual chemicals? These are shown on data sheets supplied by chemical distributors. It should be ascertained if there are any particular hazards associated with entry into the body of any of the chemicals; are any substances absorbed by the skin or inhaled through the nose? Precautions that might be necessary are the use of disposable gloves and/or goggles. Volatile compounds should be handled in a fume cupboard, which is certified as conforming to legal requirements (such as those laid down by the HSE in the United Kingdom). Fume cupboards should not be used with the front open above the displayed marks to ensure the correct airflow.
• Are there any aspects of the use of equipment or procedures that expose laboratory workers to any hazards? There are the ubiquitous procedures, such as pipetting. This should never be done by mouth, and must be done using either an automatic pipette or a device that can be attached to the end of a plastic or glass pipette. The instructions for operating equipment must be adhered to. Examples are centrifuges, spectrophotometers and equipment containing lasers or radiation sources.
• A vital part of a risk assessment is to identify methods of disposal of hazardous chemicals and biological materials. Many water-soluble compounds can be disposed of in a sink, usually after appropriate dilution. Lipophilic compounds and solvents are disposed of in specially designated bottles. Biological waste is usually placed in yellow bag to await later incineration. Used plastic pipettes and tips are placed in special containers, as are sharp objects such as syringe needles.
• The procedures to be taken in event of an accident or emergency must be clear. Chemical spills are a common occurrence and different procedures are required depending on the nature of the chemical. Dilute solutions of water-soluble, non-toxic chemicals are easily cleaned up by use of absorbent materials such as paper towels. All other potential hazards must be assessed, such as flammability, reactivity to air or water, corrosion or high toxicity; the incident should be immediately reported. Special measures will have to be taken. Flammable chemicals are absorbed with sawdust or special pads and the laboratory is ventilated maximally. Acids and alkalis should be diluted and neutralized.

1.2 THE LABORATORY RECORD BOOK

The importance of keeping a laboratory notebook is often underrated. Evidence collected for any purpose will not be credible if a contemporaneous record of events is not available. This is no less true for laboratory evidence than it is for police and forensic records. A book must be kept where all procedures, calculations, observations and results, along with the relevant health and safety forms, are kept. This should be a permanently bound book, and not a loose-leaf from which pages may be removed. Entries must be made contemporaneously in the laboratory at the time at which they occurred. This is frequently not appreciated by students who think that they will “write it up neatly” at some later time. This is unacceptable. For this reason, many hospital and research laboratories employ strategies such as forbidding record books to be removed from the laboratory, or insisting that duplicate records are kept and one copy left in the laboratory upon leaving at the end of the day. There are several essential pieces of information that must always be recorded.

• Entries must be done using a pen and not an erasable pencil. Corrections should be made by crossing out rather than deleted.
• Pages must be dated and the name(s) of experimenters be recorded. All entries of data on computers are date-stamped and not subject to later manipulation. Computer records should be backed up after each day to prevent loss.
• All details of methods, instruments and apparatus must be recorded. All details of chemicals and solutions (especially their concentrations) noted. Details of animals used must be available, including their species, age, weight and sex.
• Raw data must be carefully recorded and fully annotated. This includes any photographs or ...