No abstract

The details of the operative preparation, care, and maintenance of our colony of suprarenalectomized dogs were given in the preceding paper (1). The effect of injections of suprarenal cortical extract upon intact, as well as upon suprarenalectomized animals was described, together with its power to revive the latter from a state of acute insufficiency. It was pointed out that much of the work which has been done upon suprarenal function, as revealed by the effects of bilateral removal of the glands, is open to the serious objection that it was necessary to make the studies on animals which could hardly have recovered from the anesthesia and the effects of the necessarily severe operative procedures. In many of the observations reported in the literature moribund animals have undoubtedly been employed. The present experiments were carded out on animals maintained after operation in an active healthy condition with adequate amounts of cortical extract. The body weight had returned to the level present at the time of the first operation, and in many instances the state of nutrition had even improved. The studies were usually carded out several weeks after complete healing of the operative wounds. The sole variable factor therefore was the cessation of the daily injections of the cortical extract. No anesthesia was used in any of the experimental procedures to be recorded in this paper. We have discontinued the use of ether in the operations for removal of the glands, as we find the narcosis produced by nembutal equally satisfactory and much safer.

Investigation of the physiological function of the suprarenal glands has presented many difficulties. The intimate relation of the cortex to the medullary portion of the gland, which contains adrenalin (or its precursor), has rendered it hard to separate the cortical material from the latter substance. Furthermore, the fatal outcome of removal of the glands (in the absence of accessory cortical tissue), within a short time after operation tends to confuse the results of the surgical procedure with those due solely to ablation of the cortex. The introduction of an extract of beef suprarenal cortical tissue (1), nearly free of adrenalin and of lipids, the parenteral use of which prolongs indefinitely the life of suprarenalectomized cats, now makes it * Dr. W. M. Firor has done many of the operations for suprarenalectomy and has developed important details in the operative technique. Several animals were prepared at Princeton and shipped to Baltimore for the experimental work by Dr. Swingle. The operations during the early stages of the work were done with the collaboration of Dr. Hans Widenhom. Dr. R. Penick has done several during the past spring. The remainder of the operations, and all during recent months have been done by Weinstein and Harrop.

FIGS. 2 AND 3. Microphotographs of 2 eaniples of endometrium obtained by curettage.In addition to the set-up described above several sharp curetting instruments are needed. The size of the instrument is limited only by the diameter of the os, as no method of dilating has been developed. Meyhoefer's eye curette has been found most satisfactory, although Buck's ear curette also has been used. The cervix must be cleaned of mucous, and the curette passed through the cervix. By placing the left hand on the abdomen of the monkey immediately cephalad of the pubis, the operator may feel the knife in the fundus and may exert slight external pressure at the time the tissue sample is being scraped from the endometrium. Unless the cervix has been cleared of mucous, the specimen will often be lost on withdrawal of the knife. Epithelium of the cervix is easily distinguishable from the endometrium.The technique is not thoroughly satisfactory but does afford an opportunity for obtaining endometrial tissue (Figs. 2 and 3 ) without interfering with the continuance of an experiment.