Histochemistry of the “sexual segment” granules of the male rattlesnake kidney

Abstract

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...

Variation in seasonal ultrastructure of sexual granules in the renal sexual segment of the Northern Water Snake, Nerodia sipedon sipedon

“…In male squamate reptiles, the sexual segment of the kidney (RSS) exhibits a seasonal cycle that has been described in many studies as correlated to seasonal testicular activity and androgen synthesis (Volsøe, 1944;Saint Girons, 1957;Bishop, 1959;Burtner et al, 1964;Bauman and Metter, 1977;Weil and Aldridge, 1981;Krohmer et al, 1987). In each of these studies the RSS was hypertrophied when plasma androgen levels were elevated and regressed when androgen levels were low.…”

“…In contrast, during quiescence the number and size of the sexual granules are reduced and distributed throughout the cytoplasm in small condensed groups (Kü hnel and Krisch, 1974). Histochemical studies have shown that sexual granules contain a complex of lipids, glycogen, mucopolysaccharides, mucoproteins, and phosphatases (Bishop, 1959;Burtner et al, 1964;Prasad and Reddy, 1972;Kü hnel and Krisch, 1974). Weil and Aldridge (1985) reported that the chemical makeup of sexual granules in the Northern Water Snake, Nerodia s. sipedon, fluctuated during the active season.…”

Ultrastructure of the reproductive system of the black swamp snake (seminatrix pygaea). III. Sexual segment of the male kidney

“…Burtner et al (1965) also reported the presence of some neutral muco-or glycoprotein (PASϩ, ABϪ) and an unsaturated lipid moiety. The resemblance of the secretory granules to zymogen granules of pancreatic Paneth cell is superficial, as no enzymatic activity is discernable in the granules (Burtner et al, 1965). Kuhnel and Krisch (1974) found no detectable carbohydrates in the secretory granules of Natrix natrix and a weak reaction for proteins.…”

“…In contrast to the garter snake, Burtner et al (1965) reported that the secretory granules of the rattlesnake, Crotalus adamanteus, are principally composed of some basic protein, probably containing tyrosine, lysine, cysteine, and tryptophan, as well as small amounts of other amino acids. Burtner et al (1965) also reported the presence of some neutral muco-or glycoprotein (PASϩ, ABϪ) and an unsaturated lipid moiety. The resemblance of the secretory granules to zymogen granules of pancreatic Paneth cell is superficial, as no enzymatic activity is discernable in the granules (Burtner et al, 1965).…”

Not just a chastity belt: the functional significance of mating plugs in garter snakes, revisited

“…In many squamates (lizards, snakes, and worm lizards), the distal portion of the nephron preceding the collection ducts of the kidneys is seasonally hypertrophied or regressed in males, but not in females (for a review in natricine snakes, see Krohmer, ). This sexual dimorphism suggests that this portion of the kidney may serve a sexual function; hence this portion of the kidney has come to be called the renal sexual segment (RSS; Burtner, Floyd & Longley, ). Seasonal regression and recrudescence of the RSS is also influenced by testosterone, which further supports its sexual function in males but not in females (Bishop, ; Krohmer, ).…”