title: Familial resemblance in catecholamine changes to cold stress and maximal exercise.
abstract: Parents and children from 38 families were submitted to a cold-stress and maximal treadmill test. The number of subjects varied depending on the measurements. Plasma epinephrine and norepinephrine, blood pressure and heart rate were measured before, during and after a cold hand immersion test (in a water bath at 5 degrees C for 2 min), as well as before and after maximal exercise (modified Balke). Scores were adjusted for the effects of age and sex through multiple-regression procedures (age + sex + age X sex + age2 + age3), yielding residuals which were submitted to analysis. Characteristic variations during cold stress were observed. Maximal exercise yielded a mean aerobic power of 43 ml/kg min-1 (SD = 10), a mean maximal heart rate of 192 (SD = 10) and a mean maximal blood lactate of 65 mg/100 ml (SD = 23). Family resemblances in cold stress and maximal exercise adaptive reactions were investigated by comparison of between-family over within-family means of squares. In response to the cold stress, there were indications of family lines in induced changes for systolic blood pressure, epinephrine, and total catecholamines at 1 min after the test (p less than or equal to 0.05). Furthermore, parent-child correlations were significant and reached 0.38 for epinephrine, 0.28 for norepinephrine, and 0.34 for total catecholamines. Familial concentrations could not be detected before or 8 min after the cold stress. There are no indications of family resemblance in plasma catecholamine concentrations following exposure to maximal-exercise stress. It is concluded that genetic variation is probably contributing only moderately to catecholamine changes under cold stress and very little under exercise stress.
mesh_terms: D000293:Adolescent; D000328:Adult; D001794:Blood Pressure; D003080:Cold Temperature; D004837:Epinephrine / Q000097:blood*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood*; D005082:Physical Exertion; D013312:Stress, Physiological / Q000235:genetics*
chemical_list: D009638:Norepinephrine; D004837:Epinephrine