Suppression of Mental Stress-induced Changes by Tandospirone, an Anxiolytic, in Cardiovascular Function

Summary. Effects of anxiolytics on mental stressinduced changes in heart rate and blood pressure were investigated in 54 healthy volunteers, 21-24 years of age, by double blind protocol. The mental stress induced by a computerized color word conflict test increased heart rate and systolic and diastolic bloodpressure by 4.2 ± 1.0/min, 5.2 ± 1.9 mmHgand 5.9 ± 1.9 mmHg, respectively. Tandospirone citrate (p.o., 5 mg), a 5HTiAreceptor agonist, did not change the resting heart rate or resting blood pressure three h after administration, whereas metoprolol (p.o., 20 mg), a /?l-adrenoceptor antagonist, gradually reduced the resting heart rate and resting systolic blood pressure. Tandospirone significantly inhibited the mental stress-induced increase in heart rate three h after administration, just as metoprolol did. These findings suggested that a low dose of tandospirone selectivelyprevents the mental stress-induced changes in cardiovascular activity without affecting the resting state.