The effects of phenoxybenzamine on tyrosine hydroxylase (TH) and mRNA level in adrenal medulla of sprague dawley rats

The effects of anti hipertensive phenoxybenzamine were investigated on tyrosine hydroxylase (TH) enzyme activity and TH mRNA levels. In the present study 5 months male sprague dawley (SD) rats were used. Phenoxybenzamine was injected i.p as 20 mg/kg which prepared in the 0.9 % NaCI and 5% ethanole. TH activity was measured by detecting of formation of 3H2O as a formation of dopa from 3H-tyrosine by radioisotope technique total adrenal RNA was isolated and hybridized wit 32P labeled cDNA. TH mRNA was assayed by densitometric scanning of the autoradiograms using a densitometer. TH activity and TH mRNA levels were found to be significantly increased by the effcet of phenoxybenzamine (P

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