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C Cicalese

Publications and source records attributed to C Cicalese.

3 recordsLinked to original sources

Changes in salivary antipyrine pharmacokinetics during adolescence, correlated with age, hormonal levels and Tanner stage.

To evaluate the effect of puberty on antipyrine metabolism, we measured antipyrine pharmacokinetics in 17 healthy subjects aged 6-21 years. The subjects received a single oral dose of antipyrine, 18 mg/kg. Salivary antipyrine levels were determined 3, 6, 9, 12 and 24 h after dosing. Age, weight, body surface area and Tanner stage were highly intercorrelated. Volume of distribution (liters) was highly correlated with all of these factors. The weight-corrected clearance of antipyrine declined significantly with age (r = 0.55, p less than 0.025). Patients were classified as immature and other based on serum hormone levels (immature = females with serum estradiol less than 25 pg/ml and males with serum testosterone less than 25 ng/dl). The uncorrected antipyrine clearance was significantly lower in the immature group (mean +/- SD 22.65 +/- 6.04 ml/min) than in others (mean +/- SD 41.30 +/- 13.26; p less than 0.01). This difference disappeared when the weight-corrected antipyrine clearance was compared for these two groups. The change in uncorrected antipyrine clearance with sexual maturation appeared to be due to increased body size, probably related to the adolescent growth spurt.

Adolescent

Pubertal changes in net renal tubular secretion of digoxin.

To evaluate the effect of puberty on the net renal tubular secretion of digoxin, we measured the ratio of digoxin clearance to creatinine clearance in 23 patients aged 4 to 21 yr and correlated this ratio with both sexual maturity (Tanner stage) and chronologic age. All subjects were at steady-state levels for digoxin treatment; all had normal serum creatinine values for age as well as normal serum potassium levels. Mean ratio for immature children (n = 14, Tanner 1 through 3.5) was 1.45 +/- 0.66. Mean ratio for mature adolescents (n = 9, Tanner 4 through 5) was 0.95 +/- 0.28. The difference between the two groups was significant (P less than 0.05). When patients were regrouped by age using either 13 or 15 yr as a cutoff, the difference in ratios was no longer statistically significant. Based on 45 subjects (new and from our previous study) aged 2 mo to 80 yr, there was a significant decrease in the clearance ratio with increasing age, but when the 23 subjects aged 4 to 21 yr were analyzed separately, the correlation between ratio and age was not significant. It appears that the decrease in net renal tubular secretion of digoxin from childhood to adulthood correlates better with full sexual maturation at puberty (Tanner 4 through 5) than with chronologic age. This observation may represent a developmental change in pharmacokinetics with broader significance than for digoxin disposition alone.

Adolescent