Lodelaben (SC-39026)

Kinase experiment:

Human neutrophil elastase (HNE) activity is quantitated by two assay systems. In the first, the rate of hydrolysis of MeOS-AAPV-NA is monitored spectrophotometrically at 410 nm, in the presence or absence of Lodelaben. The elastase concentration is titrated to yield an absorption change of 0.12 to 0.14 optical density units/min, at 30°C, in 0.2 M Tris buffet, pH 8. Lodelaben and substrate are prepared in dimethylsulfoxide (DHSO). The final DMSO concentration is 10%. In the second method, the hydrolysis of [14C]elelastin by HNE in the presence and absence of Lodelaben is quantitated[1].

Animal experiment:

Pathogen-free male Sprague-Dawley rats (250 to 300 g) are used. Half are assigned at random to be given a single subcutaneous injection of monocrotaline (60 mg/kg) and the other half receive an equal volume of 0.9% saline. Half of the rats in each group are further assigned at random to receive by gavage either Lodelaben (40 mg/kg/dose) suspended in carboxymethylcellulose vehicle or an equal volume of vehicle only. The rats are gavaged twice daily starting 12 hours before and continuing for 8 days after the monocrotaline or saline injection to provide a "window" around day 4. On day 13, after the monocrotaline or saline injection, the rats are anesthetized. Pressure measurements and cardiac output are recorded 48 hours later to allow sufficient time for recovery from the effects of anesthesia. The heart and lungs are then prepared for morphological assessments[2].

References:

[1]. Nakao A, et al. SC-39026, a specific human neutrophil elastase inhibitor. Biochem Biophys Res Commun. 1987 Sep 15;147(2):666-74.
[2]. Ilkiw R, et al. SC-39026, a serine elastase inhibitor, prevents muscularization of peripheral arteries, suggesting a mechanism of monocrotaline-induced pulmonary hypertension in rats. Circ Res. 1989 Apr;64(4):814-25.