Aquaporins (AQP) are involved in bidirectional transfers of water and small solutes across cell membranes. They are present in all tissues. However, the expression of AQP-7 has not yet been demonstrated in the reproductive tract of the camelid Camelus dromedarius. The study presented here concerns the immunohistochemical evidence of aquaporin-7 (AQP-7) in different parts of the male genital tract of Camelus dromedarius. To check the immune reactivity levels of anti-AQP-7 antibody in the male genital tract of Camelus dromedarius, the testes (proximal part, distal part and rete testis), epididymis (head, body and tail), ductus deferens (initial, middle and ampullary part) and prostate gland (compact and disseminated part) were collected from 12 male camels during the rutting and non-rutting seasons and subjected to immunohistochemistry. The result showed that the highest level of AQP-7 mRNA expression was in the testis of rutting and non-rutting males compared to the ductus deferens, epididymis and prostate. In addition, the highest mRNA gene expression of AQP-7 was in rutting males compared to non-rutting males. AQP-7 mRNA expression was higher in the ret testis, the body of the epididymis, the ampullary part of the ductus deferens and the compact part of the prostate. The immune reactivity levels of AQP-7 in rutting males showed strong reactivity in the testis and prostate compared to the epididymis and ductus deferens. On the basis of the results, it can be concluded that the distribution of the AQP-7 transcript and protein varied among rutting and non-rutting seasons and that the physiological roles of AQP-7 in the transportation of lipids, energy and water should be considered the main challenge in the activity and establishment of male Camelus dromedarius fertility during the rutting and non-rutting seasons. Moreover, AQP-7 detection is critical in assessing regulation and screening for new modulators that can prompt the development of effective medication to enhance fertility during rutting and non-rutting seasons.
Keywords: Camelus dromedarius; aquaporin-7; epididymis; prostate; testes.