Harold Goss

Development and Cure of “Ring-tailed” Condition in Rats on Vitamin B6 Deficient Diets

In the course of an experiment in which sheep and cow rumen contents were being assayed for vitamin B6 by a modification of the method of Dimick and Schreffler 1 we observed, in addition to the usual dermatitis of the face, ears and paws, ring-like (see plate I) lesions on the tail. This condition was first noted after the rats had been on the depletion diet for a period of 5 to 6 weeks and it developed in about 10 out of 100 animals used during the depletion period of approximately 7 weeks. The basal diets used had the following composition: In the first assay, using diet A. factor II was supplied by feeding 0.5 cc daily of a liver filtrate concentrate prepared from Lilly Liver Extract Powder 343∗ by 5 treatments with fullers earth after the method of Lepkovsky, Jukes and Krause. 3 The filtrate secured by this procedure was further treated with 8 volumes of 95% ethanol and the resulting precipitate was discarded. The final filtrate was concentrated under reduced pressure to the point where 1 cc represented 2 g of the original liver extract powder. In the second assay using diet B a filtrate was used which had been prepared from Armours Liver Extract 70 A.S.† by similar treatment. This preparation was fed at a level of 0.2 cc daily since preliminary experiments showed that this amount supplied sufficient factor II to satisfy the growth requirement of the rat. Basal diet B contained 4% hydrogenated cottonseed oil and 4% lard. This change was made to avoid the possibility of a deficiency of unsaturated fatty acids in the diet. Since no difference was noted in the response of the rats in the two assays it is believed that both diets were equally satisfactory.

Glutathione concentration of livers and muscles of rats following injection of hypophyseal growth hormone.

We have previously reported 1 that there is an increase in concentration of glutathione in muscles of mature rats after 15 daily injections of a potent growth hormone obtained by alkaline extraction of beef pituitary. In control animals similarly treated with a heat inactivated solution of the hormone we found no such change. Analyses of the livers showed no significant change. However, if animals were sacrificed a few hours after a single injection of the potent hormone we found a decided fall in the glutathione concentration of the liver with only a slight change, if any, in the muscle glutathione. We have no explanation to offer for this sudden change in the liver but believe that it may furnish a method for estimation of the potency of the growth hormone that is more rapid than the usual method by measuring growth after 20 days of injection. It may prove to have a more important significance since by its use the fundamental biochemical reactions induced by the growth hormone may be studied quantitatively and thus it may be possible to obtain additional information concerning the chemical reactions involved in the synthesis of tissues. Mature female rats which had reached growth stasis normally were used. They were divided into 2 groups matched for weight. One group, the experimental, received a single injection of a growth hormone solution prepared according to the method of Evans. 2 In a previous trial daily injections of 1 cc. of this solution had induced an average growth of 50 gm. in 15 days in mature female rats. The control group received the same amount of the heat inactivated hormone. Both groups were injected then allowed to fast for periods varying from 8 hours to 24 hours, when they were killed.

Response of Hypophysectomized Rats to Hihly Purified Extracts of Prenant Mare Serum

Goss and Cole 1 have shown that extracts of mare serum can be prepared testing 4000 to 7000 R.U. per mg total solids (40,000 to 70,000 R.U. per mg nitrogen). The question arises regarding the nature of the hormone present in these extracts as compared to that in untreated mare serum. Evans, et al., 2 and Hellbaum 3 have reported that more than one gonadotropic hormone is present in mare serum though these reports have not been confirmed. In the first mentioned paper the male rats showing only a Leydig tissue response were possibly sacrificed too soon to expect an effect upon the seminiferous epithelium. Further, had the time of autopsy of the females been delayed beyond 72 hours corpora lutea might have been encountered following the treatment with so-called FSH fractions. The extracts prepared by these authors were relatively crude preparations. We were interested, therefore, in determining whether or not highly purified materials would give similar evidence of fractionation of gonadotropic hormones. A fraction giving pure follicular stimulation in the female with little or no effect on the interstitial tissue of the male would give evidence of a purified follicle stimulating hormone whereas a converse relationship would indicate the presence of a luteinizing hormone. Experimental. Two extracts were used: one, No. 15-19-2, tested 35,000 and the other, No. 17-76-4, 40,000 R.U. per mg nitrogen.∗ Four to 6 female rats, hypophysectomized on the 23rd day of age, were used at a given level for each extract. The intraperitoneal administration of a total of 30 R.U. over a 3-day period beginning on the 30th day of age produced ovaries averaging 116 mg for No. 15-19-2 and 127 mg for No. 17-76-4, on the 5th day after the initial injection. The extracts were also tested in hypophysectomized male rats. The results on one extract, No. 15-19-2, are shown in Table I. There was a strong interstitial cell response as is indicated by the response of the accessory organs. Two rats treated similarly with No. 17-76-4 gave like results. Thus it is seen that these extracts containing much less inert material than any previously reported for mare serum give a good follicular response in the hypophysectomized female and a strong interstitial cell response in the hypophysectomized male. In other words, in spite of the high degree of purification attained in the present extracts, no evidence was secured to support the view that mare serum contains 2 distinct hormones, one specifically affecting the interstitial tissue of the ovary and the Leydig tissue of the testis, and a second causing follicular growth in the female and germinal tissue development in the male.