Spermatogenetic Disorders in Adult Rats Exposed to Tributyltin Chloride during Puberty

Abstract

ABSTRACT. Adverse effects of tributyltin (TBT) chloride were investigated on the reproductive system in male adult rats as exposed during puberty. Fifty Sprague-Dawley rats at the age of 35 days were assigned to five different groups: negative control receiving vehicle, methyltestosterone (10 mg/kg B.W.), and TBT chloride treatments (5, 10, and 20 mg/kg B.W.). Animals were treated by oral gavage for ten consecutive days and sacrificed at 5 weeks after final treatment. The treatment of TBT chloride at the high dose of 20 mg/kg B. W. significantly decreased homogenization-resistant testicular sperm counts (p<0.05). The TBT chloride treatment at the doses of 10 and 20 mg/kg B.W. also significantly decreased caudal epididymal sperm counts (p<0.01). Some of motion kinematic parameters (motility, mean angular displacement, lateral head displacement, and dance) of sperms retrieved from vasa deference were significantly decreased in rats treated with the TBT chloride at the dose of 20 mg/kg B.W. (p<0.05). These results provide a further evidence that an exposure to TBT chloride during pubertal period in male rats produces spermatogenic disorders characterized by decreasing testicular and epididymal sperm counts and some motion parameters of sperms in the vasa deference. KEY WORDS: epididymis, sperm count, sperm motility, testis, tributyltin chloride.J. Vet. Med. Sci. 65(12): 1331-1335, 2003 Tributyltin (TBT) has been widely used as a biocide in such applications as antifouling paints of boat and for other purposes, until its use restricted in 1980's after discovery of severe damage on aquatic ecosystem caused by the agent [4,11,16]. Even after the restriction of its uses, TBT deposited in sediments remains an important exposure source for marine biota many years to come due to its relative stability under anoxic sediment conditions [4,10,11]. The bioaccumulation of TBT and its metabolites (dibutyltin and monobutyltin) in food chains and food products has lately attracted a considerable attention on human health effects [3,15,17]. Though the levels of TBT compounds were not sufficiently high to have adverse effects on human health, a possible exposure of humans to TBT compounds aroused a great concern about their toxic potential [17].A variety of reproductive toxicities of TBT compounds have been reported in rats [1,2,6,7,12,13]. The exposure of TBT chloride during preimplantation period produced early embryo loss and implantation failure in rats [6,7]. In addition, TBT chloride exposure during pregnancy has been associated with increased incidence of fetuses with cleft palate and induced fetal reabsorption in rats [1,2]. In the study of two-generation reproductive toxicity in the rat, decreases in body weight and sex organ weights were pronounced, and sperm counts of testis and cauda epididymis were also decreased in F1 and F2 neonates [12,13].In our previous report, TBT treatment in male rats during puberty decreased the weights of prostate and seminal vesicle, and increased detached debris and some sloughed cells rega...

Effects of Exposure to Genistein during Pubertal Development on the Reproductive System of Male Mice

“…Images were recorded in real-time over extended periods. For each slide, the tracks of sperm in 10 fields were recorded for approximately 2-3 min [22]. Centroids were used for estimation of the motion endpoint, which includes motility (number of sperm exceeding threshold minimum velocity/ total number of sperm), curvilinear velocity (VCL: mean frame-to-frame velocity), straight-line velocity (VSL: velocity between centroids in first and last frame tracked), average path velocity (VAP: velocity obtained from smoothing the original path), hyper-activated sperm (HYP), beat cross frequency (BCF: frequency of centroids crossing the average trajectory), mean angular displacement (MAD: time-average of absolute values of the instantaneous turning angle of the sperm head along its curvilinear trajectory), lateral head displacement (ALH: displacement of the centroid from a computer-calculated average trajectory).…”

Perinatal exposure to low doses of tributyltin chloride reduces sperm count and quality in mice

“…Previous studies showed that the sustained exposure to high dose or low dose of TBT reduced spermatogenesis in rat or mice (Omura et al, ; Yu et al, ; Chen et al, ). In addition, exposure to high‐dose TBTCl caused delayed effects on germ count in rat (Yu et al, ). The present study shows that perinatal exposure to low‐dose TBTCl is implicated in causing long lasting alterations in sperm counts and motility.…”

“…Tributyltin (TBT), widely used in agriculture and industry, is well known to induce imposex in gastropod mollusks (Smith, 1971;Oetken et al, 2004). Further studies provided evidences that TBT might act as an ED in mammals (Omura et al, 2001;Yu et al, 2003;Grote et al, 2004;Chen et al, 2008;Shi et al, 2009;Si et al, 2011Si et al, , 2012aGraceli et al, 2013). It has been reported that in utero exposure to TBT resulted in increased epididymal adipose mass in adults (Grun et al, 2006).…”

Triorganotin as a compound with potential reproductive toxicity in mammals

“…Several studies addressing the effect of TBT on male reproductive functions have been reported (16,21,(37)(38)(39)(40)(41)(42)(43)(44). A study conducted on male rats over two generations showed that testis, epididymis, ventral prostate, and body weight decreased in all groups, but mainly in the group treated with a dietary concentration of 125 mg TBTCl per g diet (21).…”

“…An increase of detached debris and sloughed cells was observed in the tubules of the epididymis and seminal vesicles were narrowed and filled with epithelial cells (42). The count of caudal epididymal and testicular sperm (41) and of homogenization-resistant spermatids decreased (21), and the motility, mean angular displacement, lateral head displacement, and dance of sperm from the vas deferens were also reduced (41).…”