Lectinhistochemical and Cytometrical Evaluation of the Corpus Luteum of the Rat at the End of Pregnancy

Abstract

Most studies on the biochemistry and structure of the corpus luteum have focused on elucidating the processes of progesterone synthesis and release. In the present work, the histochemical composition of the corpus luteum of the rat was evaluated using lectinhistochemistry on rats at the end of pregnancy (days 18-23). We also analysed the morphology of the luteal cells, to characterize the changes attributable to regression in this organ. Seven biotinylated lectins were used (CON-A, WGA, DBA, SBA, PNA, RCA and UEA-I) following pre-set protocols (ABC method). The average diameter and area of the cells and their nuclei were measured. High reactivity of the luteal cells was observed with CON-A and a lower reactivity with WGA. The capillary endothelium gave positive reactivity with WGA and to a certain extent with SBA, PNA and RCA. Vesicular structures were intensely stained with DBA, and were more abundant in sections from animals with more advanced pregnancy, which could be attributable to cellular debris, on the basis of their morphologic characteristics. There were no significant differences among the cytometric variables analysed in comparisons of the values corresponding to the different days of gestation. These observations, together with previous research, suggest that, on the day of delivery, the corpus luteum of the rat is in the very early stages of structural regression, with no changes at the morphological level, but with changes at the molecular level.

Lectin‐Binding Pattern in Ovarian Structures of Rats with Experimental Polycystic Ovaries

“…We observe a lectin histochemistry pattern that coincides, in part, with those found in the bibliography (Salvetti et al. ; Parillo and Verini‐Supplizi ; Parillo et al. , ).…”

“…Lectin histochemistry has been successfully used to characterize in situ carbohydrates of ovarian follicles in numerous species (Maymon et al 1994;Salvetti et al 2000;Desantis et al 2009). Lectins are a group of proteins which have the property of binding to certain specific sugar chain structures including those of glycoproteins (Debray et al 1981), glycolipids (Zurn 1982) and GAGs (Toda et al 1981;Bell and Skerrow 1984;Hirabayashi 2008;Desantis et al 2009).…”

Lectin histochemical pattern on the normal and cystic ovaries of sows

“…For the first time, the lectin histochemistry was efficient to identify different residues of carbohydrates in multiple ovarian structures of sows, as previously demonstrated in another species, such as rats (Barbeito et al, ; Salvetti et al, ), rabbits (Parillo & Verini‐Supplizi, ) and dogs (Parillo, Zelli, Verini Supplizi, Fagioli, & Gargiulo, ). Data of the present investigation are important to improve the comprehension of the events and physiologic interactions which occur throughout the reproductive cycle, including contact between gametes.…”

“…Lectin histochemistry (LHC) is an important technique effectively used in the identification and in situ characterization of carbohydrates in ovarian follicles of many species, such as rat, mare, pig, viscacha ( Lagostomus maximus ) and women (Acuña et al, ; Barbeito et al, ; Desantis et al, ; Maymon et al, ; Pastor et al, ; Salvetti et al, ). This technique was also used to identify glycan residues in equine and porcine cumulus–oocyte complexes in in vitro ‐ and in vivo‐matured samples (Accogli et al, ).…”