Indication |
For the treatment of malignant neoplasms of pancreas (metastatic islet cell carcinoma). |
Pharmacodynamics |
Streptozocin is an antitumour antibiotic consisting of a
nitrosourea moiety interposed between a methyl group and a glucosamine.
Streptozocin is indicated in the treatment of metastatic islet cell
carcinoma of the pancreas. Streptozocin inhibits DNA synthesis in
bacterial and mammalian cells. In bacterial cells, a specific
interaction with cytosine moieties leads to degradation of DNA. The
biochemical mechanism leading to mammalian cell death has not been
definitely established; streptozocin inhibits cell proliferation at a
considerably lower level than that needed to inhibit precursor
incorporation into DNA or to inhibit several of the enzymes involved in
DNA synthesis. Although streptozocin inhibits the progression of cells
into mitosis, no specific phase of the cell cycle is particularly
sensitive to its lethal effects. |
Mechanism of action |
Although its mechanism of action is not completely clear,
streptozocin is known to inhibit DNA synthesis, interfere with
biochemical reactions of NAD and NADH, and inhibit some enzymes involved
in gluconeogenesis. Its activity appears to occur as a result of
formation of methylcarbonium ions, which alkylate or bind with many
intracellular molecular structures including nucleic acids. Its
cytotoxic action is probably due to cross-linking of strands of DNA,
resulting in inhibition of DNA synthesis. |
Absorption |
Poor oral absorption (17-25%) |
Volume of distribution |
Not Available |
Protein binding |
Not Available |
Metabolism |
Primarily hepatic |
Route of elimination |
As much as 20% of the drug (or metabolites containing an N-nitrosourea group) is metabolized and/or excreted by the kidney. |
Half life |
5-15 minutes |
Clearance |
Not Available |
Toxicity |
Symptoms of overdose include nausea and vomiting, anorexia, myelosuppression; and nephrotoxicity. |