Victor M. Emmel

SOME OBSERVATIONS ON LIPID METABOLISM AND ADIPOSE TISSUE IN THE VITAMIN E-DEFICIENT RAT.

Summary 1. Gross, microscopic and biochemical observations were made on adipose tissue of rats receiving a diet deficient in Vit. E and rich in long-chain unsaturated fatty acids. 2. A progressive increase was found in the ratio of extractable phospholipids to non-phospholipids. 3. Studies of the uptake of P-32 indicate that the metabolic activity of phospholipids in abnormal adipose tissue is comparable to that in normal adipose tissue.

Darrow red, a new basic dye.

A new red basic dye, which has specificities similar to blue basic dyes and which exhibits metachromasia, has been named Darrow red, and is now commercially available. In a staining solution, prepared as indicated, it is stable for about 1 mo. Procedure: Dissolve 50 mg of Darrow red in 200 ml of 0.2 M acetic acid. Boil gently for 10 min; cool and filter. Stain frozen sections or decerated and hydrated mounted paraffin sections 20-30 min. Differentiate and dehydrate rapidly in 50, 70 and 95% ethyl alcohols followed by n-butyl alcohol, xylene and covering in synthetic resin.

Effects of HCl on alkaline phosphatase in kidney and intestine; histochemical and quantitative study.

Summary The inactivation of renal and intestinal alkaline phosphatases by HCl was studied by histochemical and by quantitative methods. In the mouse, guinea pig and dog the renal enzyme is inactivated at a distinctly higher pH than is the intestinal enzyme. These observations support the view that renal and intestinal alkaline phosphatases are not identical.

Pressure measurements in perfused segments of small blood vessels.

Summary A method is described for recording in vitro pressure responses from perfused segments of small blood vessels. The method permits accurate evaluation of the relationships between dose and response. For arterial biopsy specimens from the dogs mesentery, maximal pressure responses of 200 to 300 mm Hg are obtained with test doses of epinephrine at an intravascular concentration of about 1.0 γ/ml. The threshold for response is about 0.04 γ/ml. The latent period for chemical stimulation of these specimens is approximately 3 to 4 seconds.

Note from the Biological Stain Commission Laboratory

Although the data presented in the accompanying table were collected much earlier, and the report is dated 1974, there have been sufficient inquiries for information on the stability of stains to merit publication at this time. The conclusions and description of conditions preceding the tabular material are identical with the original report; some noninformative entries have been omitted from the table. While reference is made to the eighth edition of Biological Stains, testing procedures are not significantly different from those described in the current ninth edition. Although this report is derived primarily from chemical data, attention is called to the statement that “in no instance was there a perceptible change in the staining performance of any of the dyes at the time of retesting.” The laboratory work of Charles T. Willis and Nicholas Parente required for this report is gratefully acknowledged.

Absence of Liver Damage in Chicks Hypoprothrombinemic Due to Vitamin K Deficiency or Ingestion of 3,3'-methylenebis (4-hydroxycoumarin)∗

Summary 1. Hypoprothrombinemia was produced in chicks by feeding a vitamin K-free diet, or by adding dicumarol to a standard commercial diet. 2. The livers of these animals showed no gross or microscopic changes which would distinguish them from corresponding groups of control animals. 3. Fatty infiltration of the liver which occurred in some of the chicks was related to the synthetic diet employed; but was not related to the lack of vitamin K or choline, or to the degree of hypoprothrombinemia. 4. In chicks there can be produced severe hypoprothrombinemia un-associated with histologic evidence of liver damage demonstrable by the methods employed in this study.