Autoradiographic study on tissue localization of [14C]cucurbitine in mice
Abstract
Cucurbitine (3-amino-3-carboxylpyrrolidine), is an anthelmintic amino acid isolated from the seeds of Duch. Male, Swiss Webster mice were each administered iv 129 mg/kg (about 7 μCi) of [14C]]cucurbitine. At 0.33, 1, 3, 9, 24 h and 3 and 9 d after treatment the mice were briefly anesthetized with ether and frozen by immersion in dry ice/hexane. The mice were processed for whole-body autoradiography by the Ullberg technique； this process does not allow thawing or contact with solvents.
At 20 min after iv, the radioactivity was highly localized in the liver, kidney, dorsal root ganglion, tracheal cartilage and pancreas of the mice. The intense localization persisted through 24h in these tissues except for the pancreas which showed a decrease in concentration with time. There was also a moderate level of radioactivity in the nasal epithelium, GI mucosa, esophagus, salivary glands, thymus, bone marrow and Harder’s gland. By 24 h there was a marked retention of radioactivity in liver, cartilage and dorsal root ganglion. On 3 d the highest concentration was in cartilage.
Since proline and hydroxylproline are important components of cartilage and since cucurbitine is structurally similar to these amino acids, the mechanism of its retention in cartilage may involve incorporation of [14C]cucurbitine into the protein matrix. The localization in dorsal root ganglia may be linked to the altered motor activity seen after high doses.
Keywords:
At 20 min after iv, the radioactivity was highly localized in the liver, kidney, dorsal root ganglion, tracheal cartilage and pancreas of the mice. The intense localization persisted through 24h in these tissues except for the pancreas which showed a decrease in concentration with time. There was also a moderate level of radioactivity in the nasal epithelium, GI mucosa, esophagus, salivary glands, thymus, bone marrow and Harder’s gland. By 24 h there was a marked retention of radioactivity in liver, cartilage and dorsal root ganglion. On 3 d the highest concentration was in cartilage.
Since proline and hydroxylproline are important components of cartilage and since cucurbitine is structurally similar to these amino acids, the mechanism of its retention in cartilage may involve incorporation of [14C]cucurbitine into the protein matrix. The localization in dorsal root ganglia may be linked to the altered motor activity seen after high doses.