Abhrak bhasma (AB) is a type of bhasma prepared from repeated incineration of mineral mica with decoctions of about 72 herbs. The particle size
of Abhrak bhasm has been shown to be in the range of 29-88 nanometers and Fe, Ca, Si, Mg and K are found to be as major constituent. Many drugs
developed to treat Central Nervous System (CNS) disorders are unable to reach the brain parenchyma in therapeutically relevant concentrations.
The blood brain barrier protects brain parenchyma from the uctuation of plasma composition, from pathogenic agents and maintains homeostasis
of the brain parenchyma by restricting non-specic ux of ions, peptides, proteins and even cells into and out the brain. Immunohistochemistry is
being widely employed as a tool for biological studies. This study is conducted to examine the change in the continuity of Blood brain barrier by
using immunohistochemistry, once Abhrak bhasm drug is given in experimental animal and also to examine the histology of organs. In this study a
total of 30 adult albino Wistar rats of approximately 4 months age (approx. 150-200 gms) of either sex selected randomly to see the effect of Abhrak
bhasm, an ayurvedic drug on Wistar rats. The rats were weighed, marked and divided into 5 groups each consisting of six animals. In normal control
group (Group E), no drug was administered and in rest of the four treated groups (Group-A,B,C,D), Abhrak bhasm @ 36 mg/kg B.wt. was
administered orally once in each rat. Brain, liver, kidneys,spleen and blood samples were collected in 10% formalin solution after euthanizing the
rats at 0.5,2,6 & 12 hours of Abhrak bhasma drug intervention. The alterations in any of the biochemical parameters are within the tolerable limits
of liver and kidney since the dose of abhrak bhasm did not affect liver and kidneys. In the present study, the increase in ALP level may be the result
of alterations in metabolisms that occurred without any signicant alteration in histology of liver. After applying the immunohistochemistry with
the research markers GFAP, CD 34, S 100, GLUT-1 and RECA-1 on the rats in groups A,B,C and D, there was no change in the intensity of
immunohistochemistry, with respect to control. While on applying the Occludin, the intensity of immunohistochemistry was reduced in all the
treatment groups as compared to the control group. On the basis of ndings of present study it can be concluded that the therapeutic dose of Abhrak
bhasma causes changes at the level of tight junctions present in blood brain barrier in rats which is shown by immunohistochemistry with occludin
research marker. There is no toxic effect of drug on different organs of rats as no signicant changes in histology of organs are seen. More studies
need to be done to check the permeability of blood brain barrier for Abhrak bhasma drug, like calculating its concentration in brain tissues and other
vital organs of rat.
The Role of P-Glycoprotein in Transport of Danshensu across the Blood-Brain Barrier