MORPHOLOGICAL OBSERVATIONS ON THE TESTES ... - Unesp

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OLIVEIRA, c.; ZANET<strong>ON</strong>I, C. & ZIE)H, R. Morphological observations on the testes of Physalaemus euvieri (Amphibia, Anura). Rev. Chil. Anaf., 20(3):263-268, 2002.MATERIAL AND METHODFive male samples ofPhysalaemus cuvieri were used. Thespecimens were collected in Botucatu(São Paulo State - Brazil), between Juneand December, when they were in thereproductive activity period. Aftercaptured and transported to thelaboratory, the individuaIs wereanesthetized with ether and submitted tomorphologicalstudies.AThe animaIs were opened throughmedium incision from the cloaca as faras anterior limbs, exposing thereproductive organs to macroscopicanalyses. After the reduction of the testesin small pieces, they wereimmediately immersed in Bouin fixativesolution during 20 hours, washed, andtransferred to 70% ethanol solution.Then, the .material was sent to thehistological routine to be dehydrated inethanol, clarified with xylol, andembedded in paraffin. Sections of 6 ~mwere stained with haematoxylin/eosin forhistological analyses, The individuaIswere appropriately preserved as proofmaterial.RESULTSConcerning the gonadmacroscopic aspect of Physalaemuscuvieri, as to color, shape, and size, wecan conspicuous anatomic variations.However, histologically there is not adifference in the germ epitheliumarrangement. Covering the testis we canfind a thin capsule of connective tissueand smooth muscle, the albuginea tunic.The blood vessels, which exist in thistesticular capsule, are maínly destinedto the parenchyma, where a germepithelium is arranged in seminiferouslocules, Delimited by a loose connectivetissue, these locules form morphologicalunits, that is, the seminiferousFigure I, A) Testes anatomic aspect of the Physalaemus cuvieri with dark brownpigmentation in the albuginea tunic, Dissected gonad ( ) putting in evidence the internalpigmentation and the units denominated seminiferous [ocules (27x). B) Histology of theseminiferous locule (HlE, 215x) and C) Generalized representation of the cystic germepithelium: locular wall (I); interlocular tissue (2) with Leydig cells, blood capillary andpigment-containing cells; primary (3) and secondary (4) spermatogonia; primary (5) andsecondary (6) spermatocytes; primary (7) and secondary (8) spermatids; spermatozoonbundles (9) and Sertoli cells (10).264
Figure 2. Detail 01'the histologicaJ arrangement 01'the semini1'erous 10cuJi: I) spermatogonia I; 2)spermatogonia lI; 3) spermatocytes I; 4) spermatocytes 11; 5) spermatids I; 6) spermatids lI; 7)spermatozoon bundles; 8) spermatozoon in the locular lume. (H/E, A and B - 430x; C and D - 850x).elements of the gonads. In Physalaemus cuvieri, the interloculartis sue is relatively scarce, presenting apigmentation in this tissue and also in the albuginea tunic,giving the testis a dark brown coloration. Between theseminiferous units, they have a inter-Iocular tissuecomposed by Leydig interstitial cells, fibroblasts,pigment-containing cells, blood vessels, and some efferentductules (Fig. I).Each seminiferous loculehas a germ tissue with a lot ofspermatogenetic cysts orspermatocysts, that is, c1usters ofgerm celIs in different stages ofditlerentiation that occur due toa intimate morphofunctionalrelation with the Sertoli cells. Inthe cysts, cells are joined in thesame differentiation status,therefore, with a developmentsynchrony. Some cysts seIdompresent cells with smalldifferences among themselvesand, since these asynchronismsare very small, we consider thecysts as a cellular group in whichali the sexual cells are in thesame stage of differentiation(Figs. 1 and 2).The different cellulartypes were differentiated andidentified according to themorphology and cystic arrangement(Fig. 2), also representedschematicalIy (Fig. 1c).Spermatogonia - three stagesaf differentiation weredistinguished. The primordialspermatogonia or primordialgerm cells are the mostvoluminous cells of thespennatogenetic lineage, whosenuclei are irregular and with amultilobular aspect. Theypresent chromatinic granulations,beside a single,eccentric nucleolus. In general,they are very c10se to the locularwalI, and are associate to theSertoli cells which stilI haveaspect of folIicular cells and thenuc1eus is falciform. It is alsocommon that t~ese spermatogoniabe isolated or joined insmalI groups, but this do notcharacterize genn cysts. From mitotic divisions, the primary(I) and the secondary (11)spermatogonia are originated. Thesecondary ones are smaller, more irregular, and they wereidentified due to the nuclear compactation degree. Thespermatogonia I are organized as celIular cysts with a irregularaspect andhard delimitation, they are located nearthe locular wall. The spennatogonia 11suffer some aIterations,which make thenuc1ei to become more compacted and give265
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MORPHOLOGICAL OBSERVATIONS ON THE TESTES ... - Unesp

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