The comparative aspects of hystricomorph subplacenta: potential endocrine organ

Author(s):Show less -

Miglino, Maria Angelica ^[1] ; de Sa Schiavo Matias, Gustavo ^[1] ; Rigoglio, Nathia Nathaly ^[1] ; Borghesi, Jessica ^[1] ; de Castro Sasahara, Tais Harumi ^[1] ; del Portal, Maria Josephina Illera ^[2] ; del Portal, Juan Carlos Illera ^[2] ; Granado, Gema Silvan ^[2] ; Ramos, Sara Cristina Caceres ^[2] ; de Oliveira, Moacir Franco ^[3] ; Conley, Alan James ^[4]

Affiliation

^[1] Univ Sao Paulo SP, Sch Vet Med & Anim Sci FMVZ USP, Dept Surg, Ave Prof Dr Orlando Marques de Paiva 87, BR-05508270 Sao Paulo, SP - Brazil

^[2] Complutense Univ Madrid UCM, Sch Vet Med, Dept Anim Physiol, Madrid - Spain

^[3] Fed Univ Semi Arid Reg UFERSA, Dept Anim Sci, Mossoro - Brazil

^[4] Univ Calif UC Davis, Sch Vet Med, Dept Populat Hlth & Reprod, 3223 VM3B, Sacramento, CA - USA

• Document type: Journal article
• Source: BMC ZOOLOGY; v. 6, n. 1 MAY 19 2021.
• Web of Science Citations: 0

Abstract

Background The placenta of hystricomorph rodents, lagomorphs and some primates includes an unusual structure, termed a subplacenta, which essentially consists of trophoblastic cells located deep to the central implantation site within the area of decidualization. It has been suggested that the subplacenta is functionally important, although considerable controversy remains on the issue. In this context, our objective was to compare the architecture and structure of the subplacentas of different hystricomorph species, to investigate the possibility that it is active in hormone synthesis. Methods In total, the placentas of 3 capybaras (Hydrochaeris hydrochaeris), 2 pacas (Agouti paca), 5 agoutis (Dasyprocta leporina), 5 rock cavies (Kerodon rupestris) and 3 guinea pigs (Cavia porcellus) at different stages of pregnancy (early, middle and near term) were used for gross and microscopic examination. This included the preparation of latex injection casts, immunohistochemistry for steroidogenic enzymes, scanning and transmission electron microscopy. Tissue steroid concentrations were also determined. Results The gross morphology and microvascular arrangement of the subplacentas were similar among the hystricomorphs studied including ultra-structural verification of cytotrophoblast and syncytiotrophoblast in all species. In guinea pigs, trophoblast cells exhibited characteristics consistent with intense metabolic and secretory activity in general. However, immuno-histochemical evidence also indicated that subplacental trophoblast expressed key steroidogenic enzymes, mainly in the chorionic villus region, consistent with tissue steroid concentrations. Conclusions The subplacentas within placentas of hystricomorph rodent species are structurally similar and, in guinea pigs, have potential for steroid hormone secretion from, at least the early stages of pregnancy. (AU)