Studies on the behaviour of semicarbazide-sensitive amine oxidase in Sprague-Dawley rats treated with the monoamine oxidase inhibitor tranylcypromine
Fitzgerald, D.H.; Tipton, K.F.; Lyles, G.A.
Journal of Neural Transmission. Supplementum 52: 259-264
1998
ISSN/ISBN: 0303-6995 PMID: 9564625 Document Number: 497729
The possibility that increased levels of the activity of the semicarbazide-sensitive amine oxidase (SSAO) might, to some extent, compensate for the loss of monoamine oxidase (MAO) activity in the atypical form of Norrie Disease, was examined using the rat as a model. Long-term treatment with the MAO inhibitor tranylcypromine (1 mg/kg/day) resulted in sustained inhibition of MAO-A and MAO-B activities in liver arid brain. After one week, the SSAO activity in heart had increased by 79% above the control levels. This increase was maintained for 3 weeks. Since such alterations might result from enzyme induction, the turnover of the enzyme was studied in cultured cells from rat aortic smooth muscle. The time-course of recovery of enzyme activity following irreversible inhibition by MDL 72145 corresponded to a half-life of approximately 6 days for this process.