27
Section of Comparative Medicine
Perhaps the most hopeful approach for the physiologist is to determine the 'normal' limits for the various traits enumerated above. This in itself offers daunting prospects for due account would have to be taken of the effects of diurnal rhythm, season, breed, &c. However, any success would allow the introduction of objectivity into the subject of stress and welfare which has for so long been wanted.
laboratory studies of the effects of stress on animals and human beings, and extended them into more everyday situations that the significance of these responses in relation to disease processes was recognized. The apparent increases in the pressures of urban living (Carruthers 1974) the influence of life-style on liability to develop heart disease (Friedman & Roseman 1959) and the availability of stress-blocking drugs, all combined to accelerate the growth of interest in this field. If you imagine an experiment which involved inflicting on any mammalian species the full range of mental, physical and dietary changes which mankind has had to undergo, the surprising thing would be not that some of the animals developed diseases which could be attributed to failure to adapt to the new conditions, but why any species would voluntarily choose to live under such conditions. As there are many differences in both the emotional and biochemical responses of man and animals, Dr Peter Taggart, of the Middlesex Hospital, and I have been testing the reactions of the intact human to various forms of emotional, physical and thermal stress, and offer an explanation of his motivation. The easiest emotional response to elicit is anxiety. When studied in the extreme situation of parachute jumping, and in its milder forms as when climbing wet and slippery rocks, or undergoing dental surgery, anxiety caused release of adrenaline alone. As well as the well-known psychophysiological correlates of anxiety, this resulted in characteristic electrocardiographic changes, and rises in blood glucose. Aggression was more difficult to induce as a pure response, although racing-driving, traffic-driving and even public speaking (Taggart et al. 1973) provided some suitably emotive situations. The predominant response observed was an increase in noradrenaline secretion, which resulted in a rise in blood pressure and plasma lipid levels. Aversion, induced by watching violent films, caused a vagotonic reaction with slowing and increased arrhythmia of the heart, in spite of increased adrenaline secretion (Carruthers & Taggart 1973). Thermal stress is easier to reproduce. A very high ambient temperature such as a sauna bath at 100°F (37.7°C) was found to increase adrenaline secretion, which produced similar effects on the heart as anxiety (Taggart et al. 1972). Cold conditions, such as cold-water swimming and sitting in a laboratory cold-room, caused noradrenaline secretion as part of a thermoregulatory response increasing lipid mobilization and utiliza-
REFERENCES Bloom S R (1973) Postgraduate Medical Journal 49 (Suppl.), 607-61 1 Bloom S R, Daniel P M, Johnston D I, Ogawa D & Pratt 0 E (1973) Quarterly Journal of Experimental Physiology 58, 99-108 Cannon W B (1929) Bodily Changes in Pain, Hunger, Fear and Rage. 2nd edn. Appleton, New York Freeman B M & Manning A C C (1971) Comparative and General Pharmacology 2, 198-204 Langslow D R & Hales C N (1969) Journal of Endocrinology 43, 285-294 Selye H (1950) The Physiology and Pathology of Exposure to Stress. Acta Inc., Montreal
Dr Malcolm Carruthers (Department of Chemical Pathology (Research), St Mary's Hospital Medical School, London W2)
Biochemical Responses to Stress in the Environment It is only during the past ten years that to talk of stress as a primary cause of disease has become even remotely respectable in medical circles. This is because while the art of medicine has from earliest times allowed for the influence on the body of external events in qualitative terms the science of medicine, which has been increasingly dominant over the past hundred years, demanded strict quantitative proof. Only gradually have physiological and biochemical techniques developed to the point where they can begin to provide the required evidence. Early this century Cannon (1929) pioneered the study of the adrenomedullary response to stress, and attributed most of the effects he observed to 'adrenin'. This was a crude extract of adrenal tissue containing mainly adrenaline and a smaller proportion of noradrenaline, although with greater equality in carnivores than herbivores. He also put forward the idea of stress responses being related to several diseases, including hypertension. Selye (1971) was concerned with the adrenocortical response to acute stress, especially physical trauma, although he later extended his work to the influence of more long-term events on the development of cardiovascular disease. It was only when Dr Lennant Levi (1971) and his co-workers started to put together the large amount of diverse information available from
429
tion. Physical stress studied during vigorous exercise in the fit and unfit, caused the release of both
430
Proc. roy. Soc. Med. Volume 68 July 1975
catecholamines, but no consistant rise in either lipid or glucose levels because of increased use of both these metabolic fuels (Taggart et al. 1972). Carefully progressive isotonic exercise regimes were found to lower blood pressure and lipid levels within 2-3 months, and suggest that this type of physical stress may be the natural way of balancing some of the emotional stress caused by urban life (Carruthers & Taggart 1974). Also it is the safest way of indulging the noradrenaline addiction, which I believe is the factor underlying many of our self-inflicted forms of stress. The genial joys of competition, concentration, cold, caffeine and cigarettes can all be explained on the basis of the stimulant action of noradrenaline on pleasure centres in the hypothalamus. Evolution is a slow process, and we are left with the problem of stone-age biochemical responses to very different patterns of stress encountered in the nuclear age. It is in helping man to live in conformity with his nature and to cope with emotional stress by both exercise and relaxation techniques in preference to drugs, that the future of research into stress would appear to lie. REFERENCES Cannon W B (1929) Bodily Changes in Pain, Hunger, Fear and Rage. 2nd edn. Appleton, New York Carruthers M (1974) The Western Way of Death. Davis-Poynter, London Carruthers M & Taggart P (1973) British Medical Journal iii, 384 (1974) American Heart Journal 88, 1 Friedman M & Roseman R H (1959) Journal of the American Medical Association 169, 1286 Levi L (1971) In: Society, Stress and Disease. Ed. L Levi. Oxford University Press, London; p 3 Selye H (1971) In: Society, Stress and Disease. Ed. L Levi. Oxford University Press, London; p 299 Taggart P, Carruthers M & Somerville W (1973) Lancet ii, 341 Taggart P, Parkinson P & Carruthers M (1972) British MedicalJournaliii, 71
Meeting 13 November 1974 Dr R J W Rees (National Institute for Medical Research, London NW7 IAA) delivered his Presidential Address on the subject of The Impact of Animal Models in Leprosy Research REFERENCES Rees R J W (1971) InternationalJournal ofLeprosy 39, 201 (1975) Leprosy Review 46 (in press)
Meeting 19 February 1975 at the Zoological Society ofLondon,
Regent's Park, London NWJ The following demonstrations were given:
Comparative Neuroradiology Dr G du Boulay and Miss Marianne Darling
28 A Comparison of the Fundus Oculi of Captive Wild Mammals Related to their Taxonomic Grouping Mr J M Hime
The following papers were read: Introduction: Science in the Zoo Dr L G Goodwin Species Differences in Platelet Surface Glycoprotein Mr A T Nurden Vitamin D Transport: Some Comparative Studies in Vertebrates Dr A W M Hay and Mr G Watson Clostridium botulinum in Aquatic Environments Dr G R Smith and Miss Caroline J Moryson Some Comparative Aspects of Reptilian Mycoses Mr P K C Austwick and Dr I F Keymer A Carnivorous Food Structure and Human Evolution Dr M A Crawford
Meeting 19 March 1975 A joint meeting was held with the Royal Society of Tropical Medicine and Hygiene on the subject of Prevention and Control of Parasitic Diseases
The following papers were read: Prospects for Control of Helminths in Farm Animals Professor G M Urquhart (Department ofParasitology, University of Glasgow Veterinary School, Glasgow G61 J QH) Prospects for Immunological Control of Parasitic Disease Professor R J Terry (Department of Biological Sciences, Brunell University, Uxbridge, Middlesex) Chemotherapy and Chemoprophylaxis of Protozoal Diseases Dr J F Ryley (Pharmaceutical Division, ICILtd, Alderly Park, Macclesfield, Cheshire) Trypanosomiasis Dr L G Goodwin (Nuffield Institute of Comparative Medicine, Regent'sPark, London NWI 4RN) The Impact of Insecticide Resistance on the Control of Diseases Transmitted by Insect Vectors Professor J R Busvine (London School of Hygiene and Tropical Medicine, Keppel Street, London WCIE 7HT) The Control of Ectoparasites of Veterinary Importance Dr W N Beesley (Department of Veterinary Parasitology, School of Tropical Medicine, Liverpool, L3 SQA)
Section of Comparative Medicine
Perhaps the most hopeful approach for the physiologist is to determine the 'normal' limits for the various traits enumerated above. This in itself offers daunting prospects for due account would have to be taken of the effects of diurnal rhythm, season, breed, &c. However, any success would allow the introduction of objectivity into the subject of stress and welfare which has for so long been wanted.
laboratory studies of the effects of stress on animals and human beings, and extended them into more everyday situations that the significance of these responses in relation to disease processes was recognized. The apparent increases in the pressures of urban living (Carruthers 1974) the influence of life-style on liability to develop heart disease (Friedman & Roseman 1959) and the availability of stress-blocking drugs, all combined to accelerate the growth of interest in this field. If you imagine an experiment which involved inflicting on any mammalian species the full range of mental, physical and dietary changes which mankind has had to undergo, the surprising thing would be not that some of the animals developed diseases which could be attributed to failure to adapt to the new conditions, but why any species would voluntarily choose to live under such conditions. As there are many differences in both the emotional and biochemical responses of man and animals, Dr Peter Taggart, of the Middlesex Hospital, and I have been testing the reactions of the intact human to various forms of emotional, physical and thermal stress, and offer an explanation of his motivation. The easiest emotional response to elicit is anxiety. When studied in the extreme situation of parachute jumping, and in its milder forms as when climbing wet and slippery rocks, or undergoing dental surgery, anxiety caused release of adrenaline alone. As well as the well-known psychophysiological correlates of anxiety, this resulted in characteristic electrocardiographic changes, and rises in blood glucose. Aggression was more difficult to induce as a pure response, although racing-driving, traffic-driving and even public speaking (Taggart et al. 1973) provided some suitably emotive situations. The predominant response observed was an increase in noradrenaline secretion, which resulted in a rise in blood pressure and plasma lipid levels. Aversion, induced by watching violent films, caused a vagotonic reaction with slowing and increased arrhythmia of the heart, in spite of increased adrenaline secretion (Carruthers & Taggart 1973). Thermal stress is easier to reproduce. A very high ambient temperature such as a sauna bath at 100°F (37.7°C) was found to increase adrenaline secretion, which produced similar effects on the heart as anxiety (Taggart et al. 1972). Cold conditions, such as cold-water swimming and sitting in a laboratory cold-room, caused noradrenaline secretion as part of a thermoregulatory response increasing lipid mobilization and utiliza-
REFERENCES Bloom S R (1973) Postgraduate Medical Journal 49 (Suppl.), 607-61 1 Bloom S R, Daniel P M, Johnston D I, Ogawa D & Pratt 0 E (1973) Quarterly Journal of Experimental Physiology 58, 99-108 Cannon W B (1929) Bodily Changes in Pain, Hunger, Fear and Rage. 2nd edn. Appleton, New York Freeman B M & Manning A C C (1971) Comparative and General Pharmacology 2, 198-204 Langslow D R & Hales C N (1969) Journal of Endocrinology 43, 285-294 Selye H (1950) The Physiology and Pathology of Exposure to Stress. Acta Inc., Montreal
Dr Malcolm Carruthers (Department of Chemical Pathology (Research), St Mary's Hospital Medical School, London W2)
Biochemical Responses to Stress in the Environment It is only during the past ten years that to talk of stress as a primary cause of disease has become even remotely respectable in medical circles. This is because while the art of medicine has from earliest times allowed for the influence on the body of external events in qualitative terms the science of medicine, which has been increasingly dominant over the past hundred years, demanded strict quantitative proof. Only gradually have physiological and biochemical techniques developed to the point where they can begin to provide the required evidence. Early this century Cannon (1929) pioneered the study of the adrenomedullary response to stress, and attributed most of the effects he observed to 'adrenin'. This was a crude extract of adrenal tissue containing mainly adrenaline and a smaller proportion of noradrenaline, although with greater equality in carnivores than herbivores. He also put forward the idea of stress responses being related to several diseases, including hypertension. Selye (1971) was concerned with the adrenocortical response to acute stress, especially physical trauma, although he later extended his work to the influence of more long-term events on the development of cardiovascular disease. It was only when Dr Lennant Levi (1971) and his co-workers started to put together the large amount of diverse information available from
429
tion. Physical stress studied during vigorous exercise in the fit and unfit, caused the release of both
430
Proc. roy. Soc. Med. Volume 68 July 1975
catecholamines, but no consistant rise in either lipid or glucose levels because of increased use of both these metabolic fuels (Taggart et al. 1972). Carefully progressive isotonic exercise regimes were found to lower blood pressure and lipid levels within 2-3 months, and suggest that this type of physical stress may be the natural way of balancing some of the emotional stress caused by urban life (Carruthers & Taggart 1974). Also it is the safest way of indulging the noradrenaline addiction, which I believe is the factor underlying many of our self-inflicted forms of stress. The genial joys of competition, concentration, cold, caffeine and cigarettes can all be explained on the basis of the stimulant action of noradrenaline on pleasure centres in the hypothalamus. Evolution is a slow process, and we are left with the problem of stone-age biochemical responses to very different patterns of stress encountered in the nuclear age. It is in helping man to live in conformity with his nature and to cope with emotional stress by both exercise and relaxation techniques in preference to drugs, that the future of research into stress would appear to lie. REFERENCES Cannon W B (1929) Bodily Changes in Pain, Hunger, Fear and Rage. 2nd edn. Appleton, New York Carruthers M (1974) The Western Way of Death. Davis-Poynter, London Carruthers M & Taggart P (1973) British Medical Journal iii, 384 (1974) American Heart Journal 88, 1 Friedman M & Roseman R H (1959) Journal of the American Medical Association 169, 1286 Levi L (1971) In: Society, Stress and Disease. Ed. L Levi. Oxford University Press, London; p 3 Selye H (1971) In: Society, Stress and Disease. Ed. L Levi. Oxford University Press, London; p 299 Taggart P, Carruthers M & Somerville W (1973) Lancet ii, 341 Taggart P, Parkinson P & Carruthers M (1972) British MedicalJournaliii, 71
Meeting 13 November 1974 Dr R J W Rees (National Institute for Medical Research, London NW7 IAA) delivered his Presidential Address on the subject of The Impact of Animal Models in Leprosy Research REFERENCES Rees R J W (1971) InternationalJournal ofLeprosy 39, 201 (1975) Leprosy Review 46 (in press)
Meeting 19 February 1975 at the Zoological Society ofLondon,
Regent's Park, London NWJ The following demonstrations were given:
Comparative Neuroradiology Dr G du Boulay and Miss Marianne Darling
28 A Comparison of the Fundus Oculi of Captive Wild Mammals Related to their Taxonomic Grouping Mr J M Hime
The following papers were read: Introduction: Science in the Zoo Dr L G Goodwin Species Differences in Platelet Surface Glycoprotein Mr A T Nurden Vitamin D Transport: Some Comparative Studies in Vertebrates Dr A W M Hay and Mr G Watson Clostridium botulinum in Aquatic Environments Dr G R Smith and Miss Caroline J Moryson Some Comparative Aspects of Reptilian Mycoses Mr P K C Austwick and Dr I F Keymer A Carnivorous Food Structure and Human Evolution Dr M A Crawford
Meeting 19 March 1975 A joint meeting was held with the Royal Society of Tropical Medicine and Hygiene on the subject of Prevention and Control of Parasitic Diseases
The following papers were read: Prospects for Control of Helminths in Farm Animals Professor G M Urquhart (Department ofParasitology, University of Glasgow Veterinary School, Glasgow G61 J QH) Prospects for Immunological Control of Parasitic Disease Professor R J Terry (Department of Biological Sciences, Brunell University, Uxbridge, Middlesex) Chemotherapy and Chemoprophylaxis of Protozoal Diseases Dr J F Ryley (Pharmaceutical Division, ICILtd, Alderly Park, Macclesfield, Cheshire) Trypanosomiasis Dr L G Goodwin (Nuffield Institute of Comparative Medicine, Regent'sPark, London NWI 4RN) The Impact of Insecticide Resistance on the Control of Diseases Transmitted by Insect Vectors Professor J R Busvine (London School of Hygiene and Tropical Medicine, Keppel Street, London WCIE 7HT) The Control of Ectoparasites of Veterinary Importance Dr W N Beesley (Department of Veterinary Parasitology, School of Tropical Medicine, Liverpool, L3 SQA)
