Plasma and ocular prednisolone disposition after oral treatment in cats.
OBJECTIVE
To evaluate the plasma and aqueous humor disposition of prednisolone after oral administration in cats.


METHODS
Six cats were administered with a single oral dose of prednisolone (10 mg). Blood and aqueous humor samples were serially collected after drug administration. Prednisolone concentrations in plasma and aqueous humor were measured at 0.25, 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, and 5.0 h after administration by a high-performance liquid chromatographic analytical method developed and validated for this purpose.


RESULTS
Mean ± standard error (SE) of maximum plasma prednisolone concentration (300.8 ± 67.3 ng/mL) was reached at 1 h after administration. Prednisolone was distributed to the aqueous humor reaching a mean peak concentration of 100.9 ± 25.5 ng/mL at 1.25 h after administration. The mean ± SE systemic and aqueous humor exposure (AUC) was 553.3 ± 120.0 ng h/mL and 378.8 ± 64.9 ng h/mL, respectively. A high AUC(aqueous humor)/AUC(plasma) ratio was observed (0.68 ± 0.13). The mean half-life time of elimination in plasma and aqueous humor was 0.87 ± 0.16 h and 2.25 ± 0.44 h, respectively.


CONCLUSIONS
The observed high ratio between aqueous humor and plasma prednisolone concentrations indicates that extensive penetration of prednisolone to the anterior segment of the eye may occur. This is the first step that contributes to the optimization of the pharmacological therapeutics for the clinical treatment of uveitis.
Hospital de Pequeños Animales, CIVETAN-CONICET, Facultad de Ciencias Veterinarias (UNCPBA), Campus Universitario, Paraje Arroyo Seco s/n, 7000 Tandil, Buenos Aires, Argentina ; Laboratorio de Farmacología, CIVETAN-CONICET, Facultad de Ciencias Veterinarias (UNCPBA), 7000 Tandil, Argentina.
María J
MJ
Del Sole
Paula
P
Schaiquevich
Marcelo A
MA
Aba
Carlos E
CE
Lanusse
Laura
L
Moreno
D000284:Administration, Oral; D000818:Animals; D001082:Aqueous Humor / Q000187:drug effects*; D002415:Cats; D002851:Chromatography, High Pressure Liquid; D008297:Male; D011239:Prednisolone / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics / Q000494:pharmacology*; D015203:Reproducibility of Results; D013997:Time Factors; D014018:Tissue Distribution / Q000187:drug effects
D011239:Prednisolone