We documented the ontogeny of androgen receptor (AR) immunoreactivity for rat lumbar motoneurons of the sexually dimorphic motor pools, the spinal nucleus of the bulbocavernosus (SNB) and the dorsolateral nucleus (DLN), and for the sexually monomorphic retrodorsolateral nucleus (RDLN). We also assessed the ontogeny of AR immunoreactivity in the rat sexually dimorphic levator ani (LA), which is a target muscle for SNB motoneurons. Lumbar spinal cords and LA muscles from gonadally intact males at ages postnatal days (P)7, P10, and P14 and as adults were incubated with the rabbit antiserum PG-21. Half of the prepubertal males (P7-P14) received 200 micrograms of testosterone propionate (TP) 2 hours prior to death to enhance immunodetection of ARs. We found that SNB motoneurons developed AR immunoreactivity at first and achieved adult levels by P10. In contrast, the number of RDLN motoneurons with AR-immunopositive nuclei during development remained well below the adult number. Development of AR immunoreactivity in the DLN shared characteristics with both the SNB and the RDLN. AR immunoreactivity developed in some DLN motoneurons by P10, although the percentage of labelled motoneurons remained below that in adulthood. Acute TP treatment significantly increased the number of SNB motoneurons with AR-positive nuclei at P7. The LA showed a robust pattern of AR immunostaining from P7 to adulthood. Immunostaining was present only in nuclei and constituted only a subpopulation of the nuclei present in muscle. The present results confirm and extend previous results based on steroid autoradiography and steroid binding assays regarding regional and developmental differences in the expression of ARs.

THE very interesting effects of some component of crude lecithine upon the condition of diabetic animals have been discussed in previous communications from this laboratory [Hershey, 1930;Hershey and Soskin, 1931;Best and Hershey, 1932]. The symptoms exhibited by these animals and the autopsy findings indicate that the characteristic condition is largely attributable to failure of liver function. The results of these studies suggested that an investigation of the effect of lecithine on deposition of fat in the livers of normal animals might be profitable. 'The literature relevant to this subject has been reviewed in the monographs byLeathes and Raper [1925] and byMacLean and MacLean [1927]. As far as we know, the particular problem in which we are interested has not been investigated by previous workers. The experiments -were planned with a view to obtaining deposition of large amounts of fat in the livers of a group of control animals. This was accomplished by feeding a diet high in fairly saturated fats. A second group of animals comparable in every way, as far as we could determine, with the controls, received the same amount of fat as those in the control group and in izdition varying amounts of crude or purified lecithine. The results demonstrate, among other points, that crude and purified lecithine influence the accumulation of fat in the livers of the test group of animals. METHODS.White rats of the Wistar strain, weighing between 150 and 230 g., were used as test animals. Previous to the experiment they had been receiving a stock diet which was adequate in all respects. All the animals used in the experiment were apparently healthy, and great care was taken to ensure that the various groups into which they were divided for any one experiment were as similar as possible. Much time was wasted

No abstract

IN the first completely depancreatized dog which was observed for a prolonged period (70 days) in this department [Banting and Best, 1922], all the symptoms of diabetes were apparently alleviated by insulin. Later, however, several animals were kept in good condition for much longer periods of time. In these animals [Allan, Bowie, Macleod and Robinson, 1924] signs of failure of hepatic function, which autopsy findings suggested were attributable to fatty degeneration of this organ, appeared at varying intervals after pancreatectomy, but the condition did not develop when minced pancreas was added to the lean beef and sucrose diet. In a series of recent publications [Hershey and Soskin, 1931;Best and Hershey, 1932;Best, Hershey and Huntsman, 1932; B e st and Hunts m an, 1932] results have been presented which support, among others, the following conclusions: (1) that crude lecithine will prevent or alleviate the extensive fatty changes found in the livers of these diabetic dogs, (2) that purified lecithine will prevent the deposition of fat in the livers of normal rats when these animals are ingesting large amounts of fat, (3) that the amount of choline which may be derived from an adequate dose of lecithine will also prevent the fatty changes in the livers of the rats. These results raise numerous questions, one of the most interesting of which is whether choline is, like lecithine, effective in preventing or alleviating the fatty degeneration which may develop in the livers of diabetic dogs. That this question can be answered in the affirmative is the result of an investigation which has been carried out on the ten members of our diabetic colony during the last twelve months. METHODS.Very little space need be given to the description of methods. Some of these have been described in previous publications. The diabetic dogs were very carefully treated after pancreatectomy and were always in

IN two previous communications from this laboratory [Hershey, 1930; Hershey and Soskin, 1931] the remarkable effects of crude egg yolk lecithine upon the symptoms and signs exhibited by depancreatized dogs under certain conditions have been discussed. Since the depancreatized animals have been kept from 3 to 11 months before the typical condition which we believe is largely attributable to failure of liver function developed, the progress of the research has necessarily been very slow. During the past three years, however, we have had the opportunity of confirming and extending the experimental results previously reported. METHODS.The general procedures used in studying the diabetic animals have been the same as those discussed in previous communications. These animals need a great deal of care and attention, and the results of the chemical determinations on samples of blood or urine would be of little value if they were not considered with reference to the history and general condition of each animal at the time the determinations were made. To save space, a detailed report of these matters will not be included here. After the complete removal of the pancreas each animal was placed upon a diet of 300 g. of lean beef muscle and 100 g. of sucrose daily. This was the diet received by all the animals mentioned in Table I during the experimental periods which will be under discussion. The entire ration was in all cases completely consumed. The dose of insulin, which was administered subcutaneously twice a day, was adjusted in each animal after pancreatectomy to permit a slight or moderate glucosuria. The insulin dosage was usually constant throughout each experiment, and the ex-PH. LXXV. 4