. Author manuscript; available in PMC: 2014 Oct 23.

Published in final edited form as: J Clin Pharmacol. 2001 Nov;41(11):1180–1194. doi: 10.1177/00912700122012733

Table III.

Pharmacodynamic Parameters for Cortisol Suppression

Parameter	White Males	Black Males	White Females	Black Females	p-Value
Parameter	White Males	Black Males	White Females	Black Females	Gender	Race	Gender × Race
λ₁ (h⁻¹)	2.38 ± 1.51	5.58 ± 3.55	2.92 ± 1.21	4.75 ± 2.44	NS	< 0.01	NS
λ₂ (h⁻¹)	0.117 ± 0.081	0.324 ± 0.14	0.0816 ± 0.054	0.128 ± 0.109	< 0.05	< 0.05	< 0.05
L₁ (ng/ml)	0.983 ± 0.016	0.980 ± 0.020	0.991 ± 0.0067	0.985 ± 0.019	NS	NS	NS
L₂ (ng/ml)	0.0197 ± 0.016	0.0263 ± 0.019	0.009044 ± 0.0067	0.0170 ± 0.0193	NS	NS	NS
R_m (ng/ml)	67.0 ± 23.9	67.8 ± 9.51	58.0 ± 12.3	52.4 ± 7.54	< 0.05	NS	NS
IC₅₀ (ng/ml)	0.631 ± 0.607	1.30 ± 0.763	1.13 ± 0.961	1.90 ± 3.55	NS	NS	NS
ABEC (ng•h/ml)	1160 ± 701	1270 ± 372	899 ± 314	891 ± 183	< 0.05	NS	NS

Data are mean values ± SD (n = 8/group). λ₁, λ₂, slopes of biexponential decline of cortisol concentration; L₁, L₂, coefficients of biexponential function; R_m, mean baseline cortisol concentration; IC₅₀, free prednisolone concentration producing 50% of the maximum inhibition of cortisol excretion; ABEC, area between the baseline and effect curves; NS, not significant.