The phylogenetic odyssey of the erythrocyte. IV. The amphibians

• Glomski, C. A. ^[1] ; Tamburlin, J. ^[1] ; Hard, R. ^[1] ; Chainani, M. ^[1]
  1. [1] State University of New York

     State University of New York

     City of Albany, Estados Unidos

     
• Localización: Histology and histopathology: cellular and molecular biology, ISSN-e 1699-5848, ISSN 0213-3911, Vol. 12, Nº. 1, 1997, págs. 147-170
• Idioma: inglés
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• Resumen

  • Amphibians manifest permanently nucleated , ova l. fla tt e ned , bi co nvex e ry throcy tes. Th ese ce lls demonstrate a cytoske leton which is responsible for the ir morphogeneti c conversion from a sphere to an e llipse a nd impa rts to th e ir ce llul ar mass reve rsibilit y of tra umati c deformati o n. The c lass Amphibi a has the largest of all erythrocytes attaining volumes greater than 10,000 fe mto lite rs in th e Amphiuma. Th e la rge dimensions re fl ect evolutionary processes, genomic size, pl o id y a nd th e re la tive size of o the r soma ti c ce lls.

    Co nve rsely, th e e ry throcy te co unt a nd he mog lob in co nce ntrat io n of th ese spec ies are low. Occasio na l denucleated red cells can be seen in the peri pheral blood but may attain levels of 90-95% of the total circ ulating population in certain membe rs of the tribe Bolitog lossini (e.g. Batrachoseps attenuatus). These e rythropl astids re ta in th e ma rg in a l ba nd thu s re ma inin g diffe re nt fro m ma mma li a n ery th rocy tes. Embryo log ica ll y, e ry thro po iesis initi a tes in th e yo lk sac a nd th e n progresses to the kidney, li ver, and possibly spleen. The yolk sac cohort is transitory and is successive ly repl aced by the larva l and definiti ve populations of erythrocytes.

    Red cell production (a long with th rombocytopoiesis) in ad ult urode les is conducted intravascularly in the spleen.

    In anurans this organ is usually the major site although th e li ve r a lso se rves as a seco nd a ry loc us fo r this ac ti vity. Medullary (bone marrow) erythropoiesis makes its ph y loge ne t ic d e but in a nura ns a nd ty pi ca ll y occ urs d urin g he ig hte ne d he mo po iesis foll ow in g me ta mor ph os is o r hib e rn a ti o n . M a tur a ti o n of th e e ry th rocy te in th e c irc ul a ti o n is commo npl ace (especiall y in urode les) whil e prolife ration at this site is in d u c ibl e by s pl e nec to my a nd /o r he mo lysin s.

    Ery throcy te -re la te d va lu es d e mo nstrate va ri a bl e diffe rences assoc iated with age, we ight , season, gender, and environment.