The integument of necturus maculosus

Abstract

I<esuriicn por el autor, ,lldeii n. Jlan-son. 1,oyola School of 3Iedicine, Chicago.1' 1 t,egumcnto dc ?r'ectt.urus maculosus.En el prcsentc trabajo cl autor db a coiioccr una revisibn iiias o nierios coriiplcta del tegiinierito de Secturus. Tlna \wd:tdera capa chrnea existe solamento en las iiia.nos y pi&. >;n ot.ras rcgiories 1:ts superficies 1ibi.c:: dc las edlulas epitkhiicas posccn espcsas p l a c~~s apicales o ri1:irgcnes cuticulares. L t o s Glt inios prescntaii iiria estriacibn pei'pwidicular y son, en pa.i*te, productos dc secrcccih. AUrededor dc 10s labios y cn el plieguc: gular existen e6lulas ca1iciforrrit:s. Tlas cblulas de J,eydig son abundantcs. T s n i b i h existen cromat6foros pirainidalcs y rnniificdos. .\ m a luz int,ensa 10s ritelanbforos cle la tierinis se dilatan coiriplctanieiitc. I * h la oscuridnd gcneralrncnte sc contraen. JAa temperutura y cl c~l o r del forido pueden niodificar 10s ca.nihios dc (!OlOr.niiicosas, distinguihclose por cl c*aracitctr y reacctioiies colorantcs dc sii secrccci6n. 1,as prinicras cstbn rodea2cl:t.i; (It: u n a purcd muscular.En lss glBridiilas iiiii(*osas por el contimio, no se cncucnt,ran jsni5s infisculos. .\mbos t i p s de g1:indulas sc desarrollan no invuginacioncs de la c a p gci-niinativa de la cpiclcniiie y no pricdttri distingiiirse entm si en 10s priiiieros wtados. ],as ct4lulas granulnrcs no pasari nun(:a por 1111 (.stado iiiucoso. En algunos casos se ericuciit.ran tanibiitn gl:i~idulas nlixt.ns. lhiran tc la claboracibn y cqxilsibn de la, secrcccih granular sc dcut.ru~-:~ el epitctlio. Jia regtmcrtci0n tienc: lugar riictliaiitc un:t inr.agin:wiGn tic riuc'vo ctpitcilio tlthrivado tlc la rctgion interctalui. y d c t la. epititmiiis, cwlowcla superionncritc. El ~iiodo dc rcnova~se lss gl6ndul:ts inucosas no cs ni:inifipsto. T,a Inus-cu1attii.a y el el)it.clio tle 13s gLiiltlulas gr;iriulnr?s poseen iina. inei*\.:ic.ihn directa. Sobrc la siipc:i*fic.ict c'stc:rn:i clel cipitclio scct~: tor clc lus g15i I dulus iiiiicosas mist ci1 fibrar; 1 .~1 1 i i fic:iclas.],as gl2inclulas d4rniitxs so11 de dos cblases: graiiulurcs Cot iw1I !di~lic:d Cdrgt-. S r c l -i r i I ; ACTHON'Y ABSTRACT O F T H I U Y.4I'I:R I M U E D

Lumbar glands in the frog genera Pleurodema and Somuncuria (Anura: Leiuperidae): histological and histochemical perspectives

“…LGs of both Pleurodema and Somuncuria are formed by clusters of mucous and serous glands, in which a region of undifferentiated cells (or intercalary cells) was observed [for details, see Dawson (1920) and Delfino (1980) in Delfino et al. (1998)].…”

Morphological characterization of the glandular system in the salamander Plethodon shermani (Caudata, Plethodontidae)

“…Mixed glands ("Drüsen des dritten Typs" = "glands of the third type" as defined by Nicoglu, 1893), in which two-secretion glands are packed in one compartment, are not restricted to P. shermani but have long been known in the skin of amphibians (Hoyer, 1890;Nicoglu, 1893;Dawson, 1920;Delfino et al, 1986). Recent characterization of the skin in Plethodon cinereus by Sever and Siegel (2015) showed the presence of a third gland (described as a mixed gland) in addition to the typical granular and mucous glands.…”

The morphology of the dorsal and ventral skin of Triturus karelinii (Caudata: Salamandridae)

“…Therefore, we believed that these glands might be an intermediate form in the stage of conversion from serous into mucous glands. Similarly, Dawson (1920) suggested that mixed glands may be an intermediate structure in conversion from serous to mucous cells in Necturus maculosus. In contrast, Delfino et al (1982) have ultrastructurally described the development of mixed glands in Salamandra salamandra (L., 1758), Salamandra terdigitata (Dunn, 1918), Triturus alpestris (Laurenti, 1768), Triturus cristatus (Laurenti, 1768) and Euproctus platicephalus (Gravenhorst, 1879) in early larval stages.…”

“…On the other hand, there are limited reports on the secretory cycle of mucous glands. Dawson (1920) showed that mucous glands exhibited different morphologies during the secretory cycle in Necturus maculosus (Rafinesque, 1818). In the early stages of mucous glands, secretory epithelium consists of low cubic cells radially arranged around the large lumen.…”

“…According to Dawson (1920), amphibians need much more mucous secretions to keep moist of their skin in unsuitable conditions, which can be tolerated through the conversion of serous cells into mucous cells. On the other hand, in our study, which has not been published yet, we found significant correlation between the numbers of mixed glands and of serous glands in comparison to animals injected with some hormones.…”