Abstract
The pharmacological actions of 5-phenyl-1:3:4-thiadiazole (L 1538), 2-amino-5-phenyl-1:3:4-thiadiazole (L 1460) and 2-amino-5-(2'-thienyl)-1:3:4-thiadiazole (L 1458) have been studied and compared with those of other muscular relaxant drugs. The three compounds have paralysing effects in mice, rats, cats, and dogs. They block the tonic component of maximal electroshock seizures and protect against strychnine, though not against leptazol-induced convulsions in mice. Like other centrally acting paralysing drugs, they depress spinal polysynaptic transmission in doses which leave monosynaptic transmission relatively unaffected. The rigidity of the decerebrate cat is reduced but not always abolished. The compounds do not induce synchronization in epidural electroencephalogram recordings. In doses not greatly affecting muscular tone and spontaneous activity, they prolong the hypnotic effects of pentobarbitone and other barbiturates in mice. Autonomic functions are only slightly affected. The similar actions of substituted thiadiazoles and 2-amino-benzothiazoles confirm a previous hypothesis that pharmacological equivalence may result either from condensing heterocyclic nuclei with aromatic nuclei or from introducing aryl substituents into them.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- DOMINO E. F. The correlation between animal testing procedures and clinical effectiveness of centrally acting muscle relaxants of the mephenesin type. Ann N Y Acad Sci. 1956 Nov 16;64(4):705–729. doi: 10.1111/j.1749-6632.1956.tb36842.x. [DOI] [PubMed] [Google Scholar]
- FUNDERBURK W. H., KING E. E., DOMINO E. F., UNNA K. R. Pharmacological properties of benzazoles. II. Sites of action in the central nervous system. J Pharmacol Exp Ther. 1953 Mar;107(3):356–367. [PubMed] [Google Scholar]
- GOODSELL J. S., TOMAN J. E., EVERETT G. M., RICHARDS R. K. A search for more effective muscle relaxants among the glycerol ethers and dioxolanes. J Pharmacol Exp Ther. 1954 Mar;110(3):251–259. [PubMed] [Google Scholar]
- HENDLEY C. D., LYNES T. E., BERGER F. M. Effect of 2-methyl, 2-n-propyl-1,3-propanediol dicarbamate (Miltown) on central nervous system. Proc Soc Exp Biol Med. 1954 Dec;87(3):608–610. doi: 10.3181/00379727-87-21459. [DOI] [PubMed] [Google Scholar]
- LITCHFIELD J. T., Jr A method for rapid graphic solution of time-per cent effect curves. J Pharmacol Exp Ther. 1949 Dec;97(4):399-408, 3 tab. [PubMed] [Google Scholar]
- MAFFII G., TESTA E., ETTORRE R. Sintesi e proprietà farmacologiche di alcuni 1,3,4-tiadiazoli sostituiti. Farmaco Sci. 1958;13(3):187–217. [PubMed] [Google Scholar]