What is the mechanism of action of vincristine?

MECHANISM OF ACTION: Vincristine is a naturally occurring vinca alkaloid. Vinca alkaloids act as antimicrotubule agents that block mitosis by arresting cells in the metaphase. 3,4 These drugs act by preventing the polymerization of tubulin to form microtubules, as well as inducing depolymerization of formed tubules.

How does vincristine sulfate halt mitosis?

Vincristine belongs to a group of drugs known as the vinca alkaloids. Vinca alkaloids are organic compounds made up of carbon, hydrogen, nitrogen, and oxygen derived from the periwinkle plant. These drugs block cell growth by stopping mitosis by interfering with microtubule polymerization.

What is mechanism of action of vinblastine and vincristine?

Both vincristine and vinblastine bind to the microtubular proteins of the mitotic spindle and prevent cell division during the anaphase of mitosis. They arrest mitosis and cause cell death. The drugs are therefore M-phase cell-cycle specific and their effects are therefore limited to dividing cells.

Does vincristine cause hypersensitivity?

Hypersensitivity – Rare cases of allergic-type reactions, such as anaphylaxis, rash and edema, that are temporally related to vincristine therapy have been reported in patients receiving vincristine as a part of multidrug chemotherapy regimens.

What is the antidote for vincristine?

Hyaluronidase: is the recommended antidote for the extravasation of vinblastine, vincristine, vindesine, vinorelbine, vinflunine. has been reported to produce positive outcomes for paclitaxel extravasation; if used for a paclitaxel extravasation, no compress is recommended.

What is the source of vincristine?

Vincristine was first isolated in 1961. It is on the World Health Organization’s List of Essential Medicines. It is a vinca alkaloid that can be obtained from the Madagascar periwinkle Catharanthus roseus.

How does vincristine affect mitosis?

What happens if vincristine is given Intrathecally?

Vincristine has a high neurotoxicity level. If given intrathecally by accident, it can cause ascending radiculomyeloencephalopathy, which is almost always fatal. The authors report a rare case in which vincristine was accidentally injected intrathecally into a 32-year-old man.

What is the adverse effect of vincristine?

Nausea, vomiting, weight loss, diarrhea, mouth sores, dizziness, or headache may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. This medication can also cause constipation, which in some cases may become serious.

Are vincristine side effects permanent?

Some patients may experience long-term or late effects of treatment that may continue or develop months or years after treatment ends. Possible late effects due to vincristine include: Peripheral neuropathy.

What is chemo antidote?

These antidotes include isotonic (1/6 M) sodium thiosulfate for mechlorethamine (and optionally for cisplatin), hyaluronidase for the vinca alkaloids (and optionally for epipodophyllotoxins such as etoposide), and cooling with very topical DMSO and low dose hydrocortisone for the anthracyclines.

This inhibition causes mitosis to arrest at metaphase, through the disruption of mitotic spindle formation, especially during the M and S phases. Another mechanism of action of vincristine includes interfering with nucleic acid and protein synthesis by blocking glutamic acid utilization. [4] Go to: Administration

How does vincristine bind to tubuline dimers?

Vincristine binds to the tubuline dimers (tubuline is a structural protein which polymerizes to form microtubules) and inhibit the polymerization causing disassembly of microtubule structure. Disruption of the microtubules arrests mitosis in metaphase. It also inhibits DNA-dependant RNA synthesis and purine synthesis.

What does vincristine do to the mitotic spindle?

Vincristine binds irreversibly to microtubules and spindle proteins in S phase of the cell cycle and interferes with the formation of the mitotic spindle, thereby arresting tumor cells in metaphase.

How does vincristine affect the release of platelets?

Vincristine is an antitubular agent, which increases platelet counts by causing release of platelets from megakaryocytes (the microtubule system of the megakaryocyte controls the release of new platelets into circulation) and impairing phagocytosis of opsonised platelets by impairing microtubule assembly in macrophages.