Organization of cardiovascular functions under experimental emotional stress

The cardiovascular reactions to experimentally produced emotional stress were studied. Stress was produced by restraint and/or electrical stimulation of the hypothalamic defense area in mobile or immobilized animals (rats and rabbits). It was found that some strains and individuals were quite resistant to these forms of stress manifesting little if any cardiovascular disturbances. Others showed early rises in heart rate, blood pressure, etc. but soon adapted and suffered no severe damage. A third category was comprised of sensitive strains and individuals which when thus exposed to stress developed hypertension, cardiac failure and some even failed to survive the test experience. These observations, those of others working in this field, and the implications of these findings are discussed.