WATER AND FAT CONTENT OF ORBITAL TISSUES OF GUINEA PIGS WITH EXPERIMENTAL EXOPHTHALMOS PRODUCED BY EXTRACTS OF THE ANTERIOR PITUITARY GLAND

Abstract

Inj. of ant. pituitary extracts into thyroidec-tomized guinea pigs produces exophthalmos and hypertrophy of the orbital fat and extraocular muscles. Analysis of the water and lipid content of orbital tissues was made to determine which of the orbital tissue components increased following the pituitary extract injs. To determine if the reaction of the orbital tissues was a part of a more general condition, the water content of non-orbital tissues was investigated. The hypertrophy of the orbital fat in experimental exophthalmos was found to be almost entirely due to a nearly 3-fold increase in its water content. In addition, there was a definite increase in the connective tissue, but the lipid content of the orbital fat was unchanged. Most of the hypertrophy of the extraocular muscles likewise was due to water, although a small component of their increase in wt. was undoubtedly a simple growth hypertrophy. Fatty tissues in the peritoneal cavity were not increased in wt., as was the orbital fat tissue, but a definite increase in their water content was observed. This increase in these adipose tissues was much less pronounced than that of the orbital fat. No increase in the water content of pooled samples of various skeletal muscles of exophthalmic guinea pigs was noted.