الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Infertility is a major human health problem which can begin at any age. Approximately 15 % of couples are infertile, and among these couples, male factor infertility accounts for approximately 50 percent of causes. Testicular growth is important for future male fertility which shows acceleration during puberty.
This study was carried out to evaluate the histological and morphometric changes that occur in albino rat testis during pre-pubertal, pubertal and post pubertal periods. This would be of help in understanding the testicular behavior and their correlations to infertility problems.
Fifty male albino rats were used and subdivided into three groups:-
group (I) :- (pre pubertal group)
This group was classified into two subgroups:-
Subgroup IA: - included 10 rats of two weeks age.
Subgroup IB: - included 10 rats of one month age.
group (II) :- (pubertal group)
This group consisted of 10 rats of two months age.
group (III) :- (post pubertal group)
This group was classified into two subgroups:-
Subgroup IIIA: - included 10 rats of three months age
Subgroup IIIB: - included 10 rats of twelve months age.
All animals were anesthetized with diethyl ether then sacrificed by decapitation. The right testes were dissected out and prepared for the followings:-
I. Histological study:
A. light microscopic study:
1-Haematoxylin and eosin stain (H&E).
2-Masson s’ trichrome stain.
Imunmohistochemical study:
1-Androgen receptors.
2-Vimentin intermediate filament.
B. Electron microscopic study:
1-Semithin sections stained with toluidine blue.
2-Ultrathin sections prepared for transmission electron microscopic study.
II.Morphometric and statistical study:
The mean number of spermatogonia, primary spermatocytes, early and late spermatids was measured. The mean diameter of the seminiferous tubules and the mean thickness of the germinal epithelium were also measured. In addition, the mean area percentage of vimentin, androgen receptor positive cells and interstitial collagen fibers were measured. The mean thickness of the capsule was also measured.
The present study revealed that testes of two weeks old rats (subgroup IA) showed small sized seminiferous tubule covered by thin tunica albuginea capsule. Each SNT was encircled by a basal lamina and was ensheathed by a layer of flat myoid cells. Two types of spermatogonia were recognized, spermatogonia A and B. The spermatogenesis was arrested at the stage of primary spermatocytes. No spermatids or spermatozoa were detected with significant decrease of the germinal epithelial thickness and the number of germ cells compared to group II.
Sertoli cells appeared central in position to spermatogenic cells and showed deep indentation of its nuclei. Focal band of tight junction between Sertoli cells was seen. Sertoli cells showed negative reaction for AR and showed significant decrease of the reaction for vimentin compared to group II.
Examination of Leydig cells showed that it was a mixture of immature flat cells and mature rounded cells. It showed significant decrease of the reaction for AR compared to group II.
Testes of one month old rats (subgroup IB) revealed thickening of tunica albuginea capsule with increase in the diameter and thickness of SNT compared to subgroup IA. The early round spermatids were found in many tubules while late spermatids appeared in few tubules. No spermatozoa in the lumen of SNT were present. The number of germ cells showed significant increase compared to the previous subgroup.
Tight junction between Sertoli cells and junctional specialization between spermatid head and Sertoli cell were found. Sertoli cells showed significant increase of the reaction for AR and vimentin compared to the previous subgroup.
Examination of Leydig cells showed that they were a mixture of immature flat cells and mature rounded cells. It showed significant increase of the reaction for AR compared to the previous subgroup.
Testes of rats of two months old (group II) revealed significant increase of the thickness of tunica albuginea capsule compared to group I. The seminiserous tubules (SNT) appeared large closely packed, with spermatozoa in their lumena. Significant increase in the diameter and thickness of SNT was noticed compared to group I and subgroup IIIB.
All types of spermatogenic cells can be easily detected and showed significant increase of their number compared to group I and subgroup IIIB. Junctional specialization between the spermatid head and the Sertoli cell was found. Mature sperms appeared to be formed of two parts; the head and the tail.
Two types of Sertoli cells were noticed the horizontal and the vertical ones. Well developed tight junction and junctional specialization between Sertoli cells were observed. Sertoli cells showed significant increase in the reaction for vimentin and AR compared to group I and subgroup IIIB.
Leydig cells were all mature having abundance of sER, mitochondria with tubular cristae, lipid droplets and microvilli protruding from their surface. They showed significant increase of the reaction for AR compared to group I and subgroup IIIB.
Examination of testes of three months old rats (subgroup IIIA) by different histological, immunohistochemical staining and electron microscopic study showed the same results as those of two months old rats (group II).
Examination of testes of twelve months old rats (subgroup IIIB) showed significant thickening of the tunica albuginea capsule compared to all groups and subgroups. Most of the seminiserous tubules (SNT) appeared small widely separated having irregular outlines. Significant decrease of the thickness of their germinal epithelium compared to group II was noticed. Some tubules showed exfoliation of spermatogenic cells with loss of their basal epithelial lining. The number of germ cells showed significant decrease compared to group II.
The tubules were separated with increased amount of interstitial tissue containing multiple thickened congested blood vessels and few Leydig cells.
Sertoli cell appeared having small euchromatic nucleus with destruction of their processes. Their cytoplasm showed increased amounts of electron dense granules. Sertoli cells showed significant decrease in the reaction for vimentin and AR compared to group II.
Examination of the interstitium showed few mature Leydig cells and degenerated cells. In close relation to Leydig cells there was embryonic like stem cell with large euchromatic nucleus lacking heterochromatin and having large nuclear / cytoplasmic ratio. Macrophage having horse shoe shaped nucleus and large blood vessel appeared close to Leydig cells. Leydig cells showed significant decrease of the reaction for AR compared to group II