Histochemical Study of the Rat Uterine Glycoconjugate Alteration following Treatment with Exogenous Gonadotropic Hormones during the Implantation Period

Abstract

One of the female causes of infertility is anovulation which is treatable with gonadotropin hormones. These hormones affect the molecular organization of the uterus such as glycoconjugates that are the first site of contact between the blastocyst and the uterus. The objective of this project was to study the alteration of glycoconjugates on the uterine apical, Golgi zone, and basement membrane of epithelial cells and the uterine gland after hyperstimulation with pregnant mare serum gonadotropin (PMSG) (4, 8, 16, 24, and 40 IU), during the implantation period. Injection of PMSG (in experimental groups) and injection of distilled water (in the control group) were followed by HCG administration (10 IU), mating, isolation of positive vaginal plug rats, and killing at 5.5 days of pregnancy. Histochemistry was done on the pregnant uterine horns with the use of WGA, DBA, PNA, ConA, SBA, and UEA lectins. The intensity of the immunohistochemical staining was scored, and quantitative data were generated. 4 IU did not show any significant differences with the control, 8 IU had less effect on the alteration of the Golgi zone, and apical and basement membrane glycoconjugates and 40 IU had the least effects on the alteration of uterine gland glycoconjugates. Also, 24 IU had the most effect on the alteration of uterine glycoconjugates. Understanding of the effects of gonadotropin hormones at the uterine level in implantation time helps to optimize hormonal manipulation for improving the outcome of assisted reproductive procedures. It seems that the optimal dose for superovulation and less alteration in uterine glycoconjugates of rats at implantation time were induced by the administration of 8 IU PMSG.

Figure 1

Pregnant rat uterine sections of decidual area invagination (a) and reaction (b). The white arrow indicates decidual reaction and the black arrow shows the presence of immune system cells. Magnification: (a): 20 and (b): 40.

Figure 2

The comparison (mean rank) between the intensity of the apical membrane of endometrial cell reaction to different lectins in experimental (4, 8, 16, 24, and 40 IU PMSG) and control (distilled water+HCG) groups. ^aSignificant difference with control (p = 0.001). ^bSignificant difference with 40 IU and control (p = 0.001). ^cSignificant difference with 24 and 40 IU (p = 0.001 and 0.0001, respectively). ^dSignificant difference with 16 IU (p = 0.001). ^eSignificant difference with 8 IU and control (p = 0.0006 and 0.0001, respectively).

Figure 3

Intensity of the reaction of rat endometrium in apical membrane, Golgi zone, and basement membrane to different lectins in experimental (4, 8, 16, 24, and 40 IU PMSG) and control (distilled water+HCG) groups. Significant differences in the intensity of the reaction to different lectins were as follows: to WGA between 16 IU and control (p = 0.001) in the apical membrane and Golgi zone, to DBA between 24 IU with 40 IU and control (p = 0.001) in the apical membrane, between 24 IU with 16 IU, 40 IU and control (p = 0.001, 0.0001, and 0.001, respectively) in the Golgi zone, and between 4 IU with 16 and 40 IU in the basement membrane (p = 0.001 and 0.0001, respectively), to ConA between 4 IU and control with 24 and 40 IU (p = 0.001 and 0.0001, respectively) in the apical membrane and the Golgi zone, to SBA between 4 IU and 16 IU (p = 0.001) in the apical membrane and between control with 8, 16, and 24 IU (p = 0.1, 0.1, and 0.01, respectively) in the basement membrane and to UEA between 24 IU with 8 IU and control in the apical membrane (p = 0.0006 and 0.0001, respectively) and Golgi zone (p = 0.0001 and 0.0006, respectively).

Figure 4

Intensity of the Golgi zone of endometrial cell reaction (mean rank) to different lectins in experimental (4, 8, 16, 24, and 40 IU PMSG) and control (distilled water+HCG) groups. ^aSignificant difference with control (p = 0.001). ^bSignificant difference with 16 IU, 40 IU, and control (p = 0.001, 0.0001, and 0.001, respectively). ^cSignificant difference with 24 and 40 IU (p = 0.001 and 0.0001, respectively). ^dSignificant difference with control and 8 IU (p = 0.0006 and 0.0001, respectively).

Figure 5

The intensity (mean rank) of the basement membrane of endometrial cell reaction to different lectins in experimental (4, 8, 16, 24, and 40 IU PMSG) and control (distilled water+HCG) groups. ^aSignificant difference with 16 and 40 IU (p = 0.001 and 0.0001, respectively). ^bSignificant difference with 8, 16, and 24 IU (p = 0.1, 0.1, and 0.01, respectively).

Figure 6

The comparison (mean rank) of the uterine gland reaction to different lectins in experimental (4, 8, 16, 24, and 40 IU PMSG) and control (distilled water+HCG) groups. ^aSignificant difference with 40 IU PMSG and control groups (p = 0.0006 and 0.001, respectively). ^bSignificant difference with 4 and 8 IU of PMSG (p = 0.0003 and 0.0001, respectively).

Figure 7

Intensity of rat uterine gland reaction to different lectins in experimental (4, 8, 16, 24, and 40 IU PMSG) and control (distilled water+HCG) groups. Significant difference in DBA-reacted sugars of 24 IU with 40 IU and control groups (p = 0.0006 and 0.001, respectively) and in ConA-reacted sugars of 40 with 4 and 8 IU of PMSG (p = 0.0003 and 0.0001, respectively) was observed.