This year I celebrate 40 years as an MP. For all this time, I have been a staunch supporter of scientific research.

If I think back even further to my childhood in the early 1930's, the way science has changed our world is enormous.

However, it is the change brought about by medical science that impresses me most of all. I grew up in an age without antibiotics, open-heart surgery, organ transplantation, pacemakers, kidney dialysis, hip replacements, keyhole surgery, ultrasound scanning or effective drugs for high blood pressure, asthma, ulcers, cancer or mental illness. The range of treatments, diagnostic techniques and methods of preventing disease that we now take almost for granted was simply unknown in those times.

These medical advances are the end result of decades of research that have transformed our understanding of the way in which our bodies function. In this area, the UK has succeeded far beyond the measure that could be expected for a relatively small island. Many of the most important advances have been made by British researchers, including the research that won Nobel Prizes: for the structure of DNA (in 1962, the year I entered the House of Commons), the development of monoclonal antibodies, and the function of nerves, and, just last month, for discoveries relating to the regulation of cell growth that can lead to cancer.

Few people would argue against medical research, but I am still amazed at the number of people who will criticise experiments on animals without realising how crucial they have been to medical science. In a recent survey of scientists around the world who had been awarded the Nobel Prize for Medicine, three quarters of them said animal experiments had been essential to their work.

Research on animals has been crucial for most of the major medical advances of the last century, including all those listed above, that have been developed during my life. The debt we owe to the humble laboratory rat is huge. It is unthinkable that doctors might give a new drug, never before tested in any living animal, to a human patient for the first time. Modern surgical techniques are normally developed and tested out in animals before being used on patients.

We should not forget that animals themselves also benefit from animal research. Every single veterinary treatment and method of diagnosis has been researched and tested on animals. Even the most ardent anti-vivisectionist finds it difficult to refute that argument.

Despite the obvious and abundant evidence of the importance of animal research, there are still anti-vivisection groups campaigning to abolish it all, regardless of the effect this would have on medical progress. Just as animal experimentation was crucial to medical research in the past, so it will be in the future. I have discussed this issue with many scientists working on diseases from asthma and AIDS to sickle cell disease and strokes. All are adamant that progress still depends on animal research.

However, I have yet to meet a scientist who actually wants to experiment on animals. It may be necessary for their research, but they prefer to use other methods of research. Professor Nancy Rothwell, who conducts research into strokes, explained it to me by saying: "I don't like using animals. I use them because seeing people with devastating illnesses is worse. The day we don't need to use animals, I will be absolutely delighted. Until that day comes, I have absolutely no doubt that animal research must continue."

It is axiomatic that non-animal methods of research are used instead of animals whenever possible, that as few animals as possible are used in each experiment and the welfare of the animals is properly safeguarded. These three simple principles were developed by two British scientists in the 1950's. They are now regarded as fundamental to all animal experimentation, and form the basis of modern controls on animal research. It is perhaps not surprising, but I suspect not widely known, that Britain has the strictest controls of any country in the world.

One thing that does not appear to have changed at all over the last 40 years is that anti-vivisection groups continue to claim that animal experiments do not work and have not produced any medical advances. They portray scientists using animals as cruel and uncaring people who are impervious to animal suffering. Since allegations of wrong-doing are much more newsworthy than the reality of responsibly-conducted medical research. These claims tend to get repeated in the popular media. All too often the scientists involved either do not have the chance to put their side of the story, or the threat of attack by animal rights extremists deters them from putting their head above the parapet.

We have to realise that progress does not come free. Our society should understand that to find cures for diseases, there are times when animals will have to be used in research. Whilst we would all prefer if this were not necessary, the simple fact is that there is no alternative if we want future generations to be able to look back and reflect upon the medical progress during their lives.