Experimental Study Of Stem Cells In The Rat Penile Corpus Cavernosum

Objective To evaluate the stem cells of penile corpus cavernosum by detecting CD34 and stem cell antigen -1 (Sca-1) in different-month-old groups of SD rat. To evaluate the muscle-derived stem cells of penile corpus cavernosum by detecting stem cell antigen -1 (Sca-1) in different-month-old groups of SD rat.Methods We randomly selected 10 SD rats of different brood in every group of 2-month-old, 5-month-old and 20-month-old which respectively as young, strong and aging group. We got penile corpus cavernosum tissues under the ether anesthesia, which were divided into two parts, one part of it was paraffin-embedded which was used for HE staining, meanwhile, it was separately immunohistochemistry single-marked by CD34, Sca-1 and Desmin, furthermore, it was immunohistochemistry double-marked by CD34,Sca-1 and Sca-1,Desmin. Another part of it was cryopreservated by liquid nitrogen, which was used to measure the content of CD34, Sca-1 and Desmin by real-time polymerase chain reaction (RT-PCR) technology.Results The results of HE staining showed that the structure of penile corpus cavernosum of young rats was tight, which blood vessels were rich, with the month-old growing, the structure gradually became lax and the blood vessels became significantly decreased. There existed stem cell markers of CD34,Sca-1 and myogenic marker of Desmin in the penile corpus cavernosum. CD34 mainly expressed in endothecium of vascular and sinusoid, we found some scattered positive expression of CD34, which were mainly existed in membrane and cytoplasm; Sca-1 scattered along the veins and cavernous, positive staining distributed in the cell membrane and cytoplasm; Desmin mainly existed in cell membrane and cytoplasm, some nuclear staining could be seen in it. We found a very small amount of double-positive staining cells of (CD34/Sca-1) and (Sca-1/Desmin), which mainly expressed around the cavernous sinus. The expression of CD34, Sca-1, Desmin, CD34/Sca-1 and Sca-1/Desmin were significantly different between every two groups(P <0.01),morever, they were negatively correlated with the month-old (P <0.01). Conclusion The expression of CD34 and Sca-1 decreased with month-old in SD rat penile corpus cavernosum, the expression of Sca-1 decreased significantly with month-old in the smooth musule of SD rat penile corpus cavernosum. we also found a very small amount of some double-positive staining cells of (CD34/Sca-1) and (Sca-1/Desmin); there were probably existed some stem cells and muscle-derived stem cells in the rat penile corpus cavernosum.