Melatonin administration induced reactivation in the seminal gland of the soay rams during non‐breeding season: An ultrastructural and morphometrical study

Abstract

Fifteen adult Soay rams were used in this experiment. Eight animals were given subcutaneous implants containing melatonin, while the other seven animals were used as control. After 11 weeks, the rams were killed and the seminal vesicles were examined by light and electron microscope. In contrast to the control grouped animals, the melatonin treated rams showed morphological, morphometrical, and ultrastructural changes as a result of reactivation of the glandular tissues of the seminal glands. The ratio of interstitial connective tissues to glandular tissues was reduced in the treated group. Melatonin induced an evident significant increase in number and height of principal cells that showed signs of increased secretory activity; apical cytoplasmic protrusions became well developed and covering the inner surface of the glandular end-pieces, also, the basal cells were significantly increased in number. The main cytological alteration in the principal cells of the seminal vesicles in treated animals was prominent increase in the concentrically arranged membranes of sER, secretory vacuoles and glycogen granules and appearance of numerous lysosomes and multivesicular bodies. Interstitial Cajal- like cells were significantly increased in number and formed a network around the epithelium and between smooth muscle cells in the treated group. The main components of these cells were mitochondria, rER, sER, and many caveolae. The cytological alterations were accompanied by subepithelial and intraepithelial nonmyelinated nerve terminals in the treated animals. The results support the view that melatonin activates and increases the secretory activity of seminal gland in sheep.

Melatonin MT1 and MT2 Receptors in the Ram Reproductive Tract

“…In the seminal vesicles, IHC showed a nuclear location for the MT 1 melatonin receptor, while that for MT 2 was found in the cytoplasm. Very recent studies have demonstrated that melatonin treatment during the non-reproductive season reactivates the ram seminal vesicles [39] and increases their size in the Iberian ibex [40]. Therefore, it is likely that both effects may be exerted through the melatonin receptors we have here identified.…”

“…In fact, melatonin treatment reactivates the seminal vesicles during the non-reproductive season [39], increasing their size [40]. It also modulates the contraction of the vas deferens [41].…”

Effect of Melatonin on Telocytes in the Seminal Vesicle of the Soay Ram: An Immunohistochemical, Ultrastructural and Morphometrical Study

“…Moreover, TCs have also been described in human skin [Rusu et al, 2011], skeletal muscle and lung [Popescu et al, 2011], as well as in the human and rat parotid gland [Nicolescu et al, 2012a]. Our previous study [Mokhtar et al, 2016] revealed their presence in seminal vesicles of the Soay ram for the first time.…”

“…Soay rams (breed Ovis aries ) were obtained from specialist breeders in Scotland [Mokhtar et al, 2016]. The animals were kept in outdoor grass paddocks at the Animal Breeding Research Organization's field station at Dryden, near Edinburgh, during long summer days with 16 h of light and 8 h of darkness, and were fed a standardized diet of grass pellets (500 g/animal; Vitagrass, Grange-over-Sands, UK) given daily.…”

New Description of Telocyte Sheaths in the Bovine Uterine Tube: An Immunohistochemical and Scanning Microscopic Study

“…Telocytes in the duodenum established a close contact with neuroendocrine cells as well as eosinophils, which might be involved in immune response [Cantarero Carmona et al, 2011]. Telocytes mediate activation of progenitor cells to repair different tissues and organs: heart, lung, skeletal muscle, skin, meninges, choroid plexus, eye, liver, uterus, urinary system [Bei et al, 2015], and ram seminal vesicles [Abd-Elhafeez et al, 2017;Mokhtar et al, 2016]. Telocytes may have a protective function against oxidative stress and cellular aging in the lung [Zheng et al, 2014].…”