Distribution and localization of dantrolene-Na in the organs of mice has been studied, using whole body frozen sections by the aid of fluorescent macro-and microscopic techniques. The results obtained in these experiments were compared to the tissues prepared by wax-embedding techniques. Uptake of the drug by isolated rat organs and dissected fresh locust thoracic muscle has also been examined.
Based on present studies, dantrolene-Na was not distributed uniformly throughout the body. It was mainly accumulated in intestine and liver and partly in kidneys. Dantrolene accumulation was not dose-dependent. However, length of administration time was quite effective on the pattern of distribution. At shorter intervals it was mainly accumulated in intestine, liver and slightly in kidney. Longer exposure to the drug resulted in more intense accumulation in intestine and liver.
Comparison of frozen and fresh material to fixed sections further supports the previous investigations that fixation procedures grossly alter the normal state of tissues and inevitably give rise to artifactual observations.