Inhibitory effect of alternariol on nitric oxide synthase in different parts of rat brain

Hassan MY Osman


Alternariol (3,4,5 trihydroxy 6-methyl dibenzoxy-a –pyrone) is a metabolite result of various strains of alternariatenuis organism. Its structure has closeness to cannabinol subordinates. The impact of the alternariol on nitric oxide snythase (NOS) extracted from distinct parts of rat brain; particularly: frontal cortex, basal ganglia, cerebellum, pons, medulla oblongata was considered. Kinetic studies were done to decide the sort of inhibition of NOS and the inhibitor dissociation constants (KI) by alternariol. The outcomes showed that alternariol inhibited NOS of the cortex, medulla oblongata and cerebellum more than that of alternate parts of the brain. These parts are in-charge of observation, tactile, psychic exercises and reflex focuses of breath. The inhibition of these enzymes increased with increasing the dose of alternariol added to the examined blend, i.e., the inhibition was dose dependent and of the competitive type. The estimations of KI for alternariol –NOS complexes shifted from 1.8 to 5.6 mM. The distinction in the level of inhibition of the extracts of these brain parts could be ascribed to the slight contrast in the structure, i.e. course of action of their amino acids (isozyme phenomenon) and to their particular gene loci.


Keywords: Alternariol, Nitric oxide synthase, Brain parts, Inhibition

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