The close relation existing between structzlre avtd functiolz makes it desirable to be fully informed as to the details of structure of the d i f e r e d segments of the r e m l tubules. CARL H L T R~, 1917It is common knowledge that the brush border of the proximal tubule of the vertebrate kidney stains positively with the periodic acid Schiff method, and that the prominent alkaline phosphatase activity of the proximal convoluted tubule shows its greatest concentration in the brush border. We believe, from references to these topics in the literature and our own impressions before beginning the present study, that it is not common knowledge that there is no fixed relationship between the extent of the brush border, periodic acid Schiff reaction and alkaline phosphatase activity, but that this varies from species to species. Some species show a brush border from end to end evenly demonstrated by either of these methods. Most, however, show a tendency on the part of either or both to vary in intensity. These arc iiot random fluctuations, but occur in such a way as to divide the tubule into definite segments.
attachment, or by some other, as yet unknown, mechanism. Such inactivation might also serve as a possible cause for infertility among otherwise physiologically normal couples.The object of this study has been to determine whether or not the secretions of the uterine cervix contain hemagglutinins, as an initial step in an effort to work out the possible physiological basis for ABO selection. The impetus for the study stemmed from the feeling that the known facts regarding the consequences to the fetus of ABO isoimmunization (see 7) were not sufficient to account for the magnitude of selection effects postulated for ABO incompatible matings. The detection, some 30 years ago, of hemagglutinin in the cervical fluid was apparently limited to the analysis of a single sample (8).All the women investigated in the course of this study were patients in the Out-Patient Gynecology Clinic of the University Hospital. Their reasons for the clinic visit were varied; only five were seen because of failure to conceive and in whom the cause of infertility was still unknown after careful study of the marital partners. The collection of cervical secretion depended only on whether or not a sample could be obtained from any particular woman. Blood for typing was obtained at the same time. All secretions were frozen soon after collection and all were tested within a period of 5 days.The method of testing was as follows. To each tube containing the sample, which was usually quite small, was added 0.15 ml of saline. Because the quantity of secretion obtained varied from subject to subject, the dilution factor is variable. The contents of the tube were then thoroughly agitated with an applicator, the tube was centrifuged, and the clear supernatant fluid was tested with fresh A,, B, and 0 red blood cells. All tests were performed in microtubes (6 by 50 mm) to which 0.01 ml of a 2 percent washed red blood cell suspension was added to 0.01 ml of the diluted secretion. The tests were allowed to stand for 1 hour at room temperature and were read macroscopically both before and after centrifugation.
The histochemistry of the "sexual segment" granules of the kidney of male diamondback rattlesnakes has been studied to define the nature of these androgenitally responsive granules. The kidneys were variously fixed and sections stained with a number of acid dyes, as well as by a variety of carbohydrate, lipid, and protein histochemical methods. The results indicate that "sexual segment" granules bind acid dyes strongly, contain some lipids and neutral glyco-or mucoproteins, much tyrosine and lysine, and some tryptophan and cysteine. A resemblance, concluded to be superficial, is noted between the histochemical properties of zymogen granules and the predominantly proteinaceous "sexual segment" granules.The existence of a macroscopically hypertrophied segment of the distal tubule of snake and lizard kidneys was first observed by Gampert in 1866. Not until early in this century, however, was the morphology and histology of this segment investigated. 'Tribondeau and Bongrand ('02), Tribondeau ('03), and Regaud and Policard ('03a,b,c) noted that in male snakes and lizards the hypertrophied, or "preterminal" segment of the renal distal tubule was greatly engorged with discrete microscopic granules. Because of this sexual dimorphism and the fact that this segment was found to enlarge seasonally in males at the same time that the testes become functional, Regaud and Policard ('03c) termed it the "sexual segment," and the granules it contains the "sexual granules." These authors' reports include complete histological details and reconstructions of nephrons of six species of snakes, and describe investigations of the effect of various fixing and staining procedures on the appearance of the nephron.Subsequent histological work (Reiss, '23; Cordier, '28; Courrier, '29; Herlant, '33; KehI, '35; Forbes, '41; Reynolds, '43; Fox, '52) on reptilian kidneys has dealt mainly with establishing species characteristics and demonstrating androgenic control of "sexual secretion." Fox ('52) in particular reviews the work on seasonal variations in the sexual segment. Although Forbes ('61) states that during the secretory phase the distal tubules contain "protein-like" granules, no histochemical or biochemical in-J. MORPH., 116 189-196. vestigations appear to have been done on this segment of the nephron of male snakes. This study reports a histochemical investigation of the nature of the sexual granules in male rattlesnake kidneys. MATERIAL AND METHODSBlocks of fresh kidneys from male diamondback rattlesnakes (Crutalus adamant e u s ) were fixed at room temperature for one day in 70% ethanol, Zenker-formol, and Lillie's ('54) aqueous mercuric formalin, and for two days in 10% aqueous buffered formalin and Bouin's fluid. The tissue was processed as usual through paraffin, and sections were cut at 6 u.A routine hematoxylin-and-eosin stain was done after all fixatives for general oversight. Since Regaud and Policard ('03c) reported a pronounced eosinophilia of the sexual granules following fixation in Zenker's fluid, staining with...
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