Continuous “Nisentil” and Suxamethonium in Anaesthesia

It is, however, clear that a high level of serum T.S.H. can be found in cases without ophthalmopathy. If these cases of ophthalmopathy without thyroid disorder are accepted as the same disease, then ophthalmopathy can also exist without a high level of circulating T.S.H. Thus our assay results could best be explained by assuming that there were two factors involved-one which produces exophthalmos and one which produces thyrotoxicosis. Although both appear to be present in thyrotoxicosis with severe eye signs, they need not necessarily be combined or produce both effects in the one patient. This suggestion has already been made as a result of experimental work in animals, which also implies that the other factor may be derived from the pituitary. Brown Dobyns (1946) observed that highly purified T.S.H. had relatively little effect in producing exophthalmos in animals. Jefferies (1949) showed that iodination of pituitary extracts inactivated the T.S.H. principle but left some exophthalmos-producing reaction. Dobyns and Steelman (1953) extended the previous observations and were able, by repeated extracting, to produce two substances from the pituitary. In testing these two substances on animals they showed that one contained a T.S.H. free from exophthalmosproducing substance and the other an exophthalmosproducing substance virtually free from T.S.H. These observations, combined with our findings, permit us to support the contentions of De Robertis (1948) and Purves and Griesbach (1949) that T.S.H. alone is not the cause of the development of exophthalmos, and would suggest that the pituitary is also the source of a separate factor,,capable of producing exophthalmos.