title: Decreased beta-adrenergic sensitivity in insulin-dependent diabetic subjects.
abstract: To study beta-adrenergic sensitivity in diabetes mellitus, we performed isoproterenol sensitivity tests in 34 insulin-dependent diabetic patients and 10 age-matched normal subjects. beta-adrenergic sensitivity [defined as the dose of isoproterenol required to increase the resting heart rate by 25 beat/min, (I25)] was significantly higher in the diabetic group (4.07 +/- 1.4 micrograms, mean +/- SD) than in the normal group (2.02 +/- 1.49 micrograms). A comparison of I25 of normal subjects and diabetic patients as a function of age showed that the latter were significantly less sensitive to beta-adrenergic stimulation at all ages (P less than 0.01). In diabetic patients, beta-adrenergic sensitivity also increased with the duration of diabetes (r = 0.64, P less than 0.0005), but the correlation was stronger when the age of the patients and the duration of the diabetes were both taken into consideration (r = 0.72, P less than 0.0005). We conclude that beta-adrenergic sensitivity is diminished in patients with type I diabetes mellitus of all ages.
mesh_terms: D000328:Adult; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000503:physiopathology; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007545:Isoproterenol; D008297:Male; D008875:Middle Aged; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D013997:Time Factors
chemical_list: D006442:Glycated Hemoglobin; D007545:Isoproterenol; D011943:Receptors, Adrenergic, beta