Vidarabine (adenine arabinoside, Vira-A) is an adenine nucleoside analogue containing arabinose in place of ri-bose. It is obtained from cultures of Streptomyces an-tibioticus and has activity against HSV-1, HSV-2, VZV, CMV, HBV, poxviruses, hepadnaviruses, rhabdoviruses, and certain RNA tumor viruses.

Vidarabine's specific mechanism of action is not fully understood. Cellular enzymes convert this drug to a triphosphate that inhibits DNA polymerase activity. Vidarabine triphosphate competes with deoxyadeno-sine triphosphate (dATP) for access to DNA poly-merase and also acts as a chain terminator. Although vidarabine is incorporated into host DNA to some extent, viral DNA polymerase is much more susceptible to inhibition by vidarabine. Vidarabine also inhibits ri-bonucleoside reductase and other enzymes. Resistance occurs as a result of DNA polymerase mutation.

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Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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