یک روش ساده برای اندازه گیری هیستامین و فعالیت آنزیم هیستیدین دکربوکسیلاز در مغز موش آزمایشگاهی

The content of the histamine in most mammalian tissues is very low.    Thus , presentation a simple and sensitive method to assay the histamine    content in crude extracts tissues is required .           In this work ,we presented a simple method for the measurement of the    histamine. 2 mg of rat brains was homogenized in 5 ml of 0.5 M HClO4 .The    homogenates were centrifuged (3000*g , 3 min )and supernatants were    adjusted to pH 5 with 0.4 M HCl. Then the precipitate was removed by    centrifugation (3000*g, 5 min) , and the supernatants were put into a micro    centrifuge filter tube ( exclusion molecular weight 10000,Millipor ) and    centrifuged at 3000 *g, for 5 min and supernatants was put into a tube .The    histamine was measured spectrophotometrically using 2,4,6-trinitrobenzen    sulfonate ,at 420 nm. One unit of enzyme activity is defined as the amount     of enzyme which will produce 1 micro mole of the histamine per min at 25° C.           The results presented in this work indicated that the highest content of    histamine level and histidine decarboxylase  were in hypothalamus.           The results obtained here clearly showed that this method  is simple,    sensitive , reliable and could be applied to assay histamine content  and    histidine decarboxylase activity in the brain.