Toxic effects of cadmium on testis of birds and mammals: a review.

In humans and other mammals, cadmium (Cd) causes various damages to different organs and tissues of the body. This review presents a comprehensive overview on the effect of Cd on the structure of seminiferous tubules, Leydig cells and blood vessels in the testis. The main observation of the effect of Cd is destruction of the seminiferous tubules with severe necrotic areas. Damage is to all stages of developing germ cells by inducing their structural changes and the apoptotic cell death. Sertoli supporting cells are considered the most vulnerable cells. Their damage results in cytoplasmic rearrangement and disruption of inter-Sertoli tight junctions resulting in increased permeability of the blood-testis barrier, structural changes in the Leydig cells and decreased testosterone secretion. After long time of Cd exposure an increase of the amount of interstitial connective tissue occurs. In blood vessels Cd exposure causes various morphological and physiological changes in vascular endothelial cells and smooth muscle cells. In humans and other mammals, the range of effect depends on the dose, route, ways, and duration of exposure. After necrosis of the sensitive cells Cd produced lesions in surrounding tissue and activate free cells. Atrophy of the seminiferous tubules is followed by Leydig cell regeneration and interstitial revascularization. In birds, spermatogenic cells underwent irreversible degeneration or atrophy of seminiferous tubules in the absence of significant vascular lesions.

An immunohistochemical observations on the oviduct of the goat.

The oviduct has an important role in regulating transport of gametes and fertilization. The main role in these functions has a smooth muscle cells and ciliated epithelium lining the oviduct. All functions are under the influence of hormonal and nervous system. The objective of this study was immunohistochemically to examine the following structures: lining epithelium, smooth muscle cells, elastic fibres and nerve fibres. For this purpose, the following antibodies were used: cytokeratin 18, S-100 protein, acetylated α-tubulin, smooth muscle actin, desmin and elastin. Ciliary and secretory cells of the lining epithelium were positive for cytokeratin 18 and S-100 protein. Cilia and the basal body-associated structures of ciliary cells were positive to acetylated α-tubulin. Smooth muscle cells (SMC) in mucosa and of the muscular layer were positive for α-smooth muscle actin (SMA) and desmin. High density of nerve fibres positively reacted to acetylated α-tubulin and S100 protein was present in the mucosa, muscular layer and serosa. Elastic fibres positive for elastin form a dense network at the base of the mucosal folds and in the muscle layer. A dense network of these fibres is accompanying the blood vessels. It is supposed that together with smooth muscle cells they are involved in the transport of ovum and in blood flow regulation.

Innervation of the circumvallate papilla of the cat tongue.

Immunohistochemically, the distribution of S-100 protein and acetylated tubulin-positive nerve fibres was studied in the circumvallate papilla and its taste buds (TB) in the adult cat. The immunostaining for acetylated tubulin demonstrated an extensive innervation of the circumvallate papilla. Vegetative ganglionic cells were found in the central area of papilla, whereas fine nerve fibres were concentrated under epithelium. Individual positive axons were seen in relation to TB. Nerve fibres enter the TB and branch out among the supporting and sensory cells. Some nerve fibres reach the apical surface of the TB, including the taste pore. Nerve fibres positive for S-100 protein were observed as dense nerve plexus located in the core of the papilla. Satellite cells localized inside the papilla were seen to surround the ganglionic cells. Bands of fine nerve fibres were present under lining epithelium, mainly at the base of the TB. A weak reaction was displayed by taste bud cells and surrounding epithelial cells as well as by the epithelial cells of the papillary side of the moat. A dense network of the nerve fibres was present among the glandular acini and surrounding the ducts of the serous Ebner's glands.

The retention of cadmium and selenium influence in fowl and chickens of F1 generation.

The retention of cadmium and selenium influence on Cd retention in the muscle, liver and kidneys of hens, chickens and in eggs was studied. Cadmium (Cd) as cadmium chloride (CdCl(2)) and selenium (Se) as sodium selenite (Na(2)SeO(3)) were added to feed at dosages: group 0-control, group 1-20 mg/kg Cd, group 2-30 mg/kg Cd + 4 mg/kg Se. The birds were exposed to Cd for 8 weeks. Cadmium level in hens and cocks was found highest in the kidneys, followed by the liver and muscle. Se supplementation resulted in Cd increase in the muscle tissue and in the reduction of Cd content in the liver and in significant decrease in the kidneys (p < 0.05). A higher Cd level in the yolk and lower in the white was noted in both experimental groups. Nonsignificant increase of Cd in eggs was noted in experimental groups with Se supplementation. Level of cadmium in organs of 7-day-old chicks hatched from Cd-treated hens in both experimental groups was low but the tendency to accumulate preferentially the Cd in the liver and kidneys was recorded. Supplementation of selenium in hens and cocks was not reflected in the decrease of Cd in these two organs of F(1) chickens but was reflected in increase in the muscle. In spite of relatively high Cd levels in the organs of layers no layer-egg-chickens transfer was observed. It was confirm that kidneys and liver are organs more attacked by dietary cadmium than muscle. Supplementation of low dose of Se resulted in decrease of cadmium deposition in analyzed organs.

The presence of acetylated tubulin in the pig thymus.

Immunohistochemical localisation of acetylated alpha-tubulin was investigated in pig thymus using a mouse monoclonal antibody. Positive reaction to acetylated tubulin was observed in the cells involved in Hassall's bodies localized in the medulla region. Reacting product displayed a homogenous, fine or coarse granular character. The reacting peripheral cells of Hassall's bodies produced crescent or annular formations. Inside the Hassall's bodies the centrally located cells were unreactive. The presence of the acetylated tubulin confirms positive cellular structures in these cells. Differences in the character and intensity of staining in the epithelial cells may confirm transformation of the epithelial cells during the formation of the Hassall's bodies and/or the presence of the neural crest derivative in the development of the thymus.

Immunohistochemical demonstration of myoid cells in the testis and its excurrent ducts in the domestic fowl.

(1) Immunohistochemical methods and three antibodies (against actin, desmin and smooth muscle actin) were used to demonstrate the myoid cells in the domestic fowl testis and its excurrent ducts. (2) A positive reaction to actin, smooth muscle actin and desmin was found in the myoid cells of peritubular tissue of the testis and in rete testis, ductuli efferentes and ductus epididymidis. (3) In the testis myoid-reactive cells form a single layer. In the rete testis, ductuli efferentes and the ductus epididymidis reactive myoid cells form a main component of the stroma. (4) Positive reaction to actin, smooth muscle actin and desmin was also observed in the myoid cells of the tunica albuginea and in the wall of blood vessels in the testis and epididymis, indicating a contractile function for the testicular capsule.

Immunohistochemical localization of S-100 protein in the pig pituitary gland.

Immunohistochemical localization of S-100 protein was studied in anterior, intermediate and posterior lobe of the pig pituitary gland. Two immunopositive cells for S-100 protein were identified: the folliculo-stellate cells (FSc) in the glandular lobes and the pituicytes in the neural lobe. In the anterior lobe, immunoreactive folliculo-stellate cells were scattered among secretory cells. In the area where the secretory cells form strands and follicle-like groups the positive cells were concentrated in groups. In the intermediate lobe, S-100 protein-positive cells were located sparsely among secretory cells and next to secretory follicles and the pituitary cleft. These FSc were more voluminous and displayed fewer cytoplasmic processes. In the neurohypophysis, positive reaction for S-100 protein was seen in the pituicytes. These cells were distributed singly or concentrated in groups. The distribution, and morphologic characteristics of the FSc in the glandular lobes and the pituicytes in the neural lobe in the pig indicate different origin of both S-100 protein-positive cells.

Immunohistochemical demonstration of vimentin and S-100 protein in the kidneys.

Vimentin and S-100 protein expression was studied in the kidneys of adult sheep and goat using immunohistochemistry. Vimentin was detected in the podocytes, mesangial cells of the glomerulus, in the endothelium of renal capillaries and renal stromal cells. In collecting tubules, ducts and nerves of the renal papilla, S-100 protein was expressed.

Expression of cytokeratins in the urinary passages.

The distribution of Pan cytokeratin and cytokeratin 18 in the dog and sheep urinary bladder and ureter as seen by immunohistochemistry using monoclonal antibodies is described. Both cytokeratins were observed in the urinary bladder and ureter of the studied species. Differences in their localization are described.

The effect of phenyl mercury on reproductive performance in laying hens.

The effect of phenyl mercury with and without selenium on the egg production of laying hens and on the fertility, hatchability and properties of eggs was studied. Mercury was administered via the feed at dosages of 5 ppm, 30 ppm, and 30 ppm Hg + 4 ppm Se, for 56 days. After two months, egg production decreased by 8.18% and 7.74% in hens fed 30 ppm Hg, and 30 ppm Hg + 4 ppm Se, respectively. Egg weight decreased in all experimental groups. In comparison to the controls, these results were highly significant (P < 0.01) in hens fed 30 ppm Hg and 30 ppm Hg + 4 ppm Se and significant (P < 0.05) between hens fed 5 ppm Hg and 30 ppm Hg. Fertility rate and hatchability were not affected. Mercury exposure did not affect egg shape, egg-white height, egg-shell hardness or yolk colour. Both egg-shell thickness and weight decreased in all experimental groups. In the group supplemented with selenium there was a nonsignificant improvement in egg production, hatchability and all qualitative properties of eggs in comparison with the group without selenium supplementation. Residual mercury levels in egg yolk greatly surpassed the level found in the egg white: the highest values were measured in the group fed 30 ppm Hg. The addition of selenium had a protective effect upon residual Hg deposits in the yolk, but not in the egg-white.

The effect of cadmium treatment on breeding hens and cocks and early viability of their chickens.

The effect of cadmium, with and without selenium, on breeding hens and cocks and their offspring up to 7 days of age was studied. In adult birds, the body weight, mortality rate, pathological changes and cadmium level were determined. In chicks, the mortality rate and level of cadmium were evaluated. Cadmium as cadmium chloride was orally administered to the hens at three dosages: 3 ppm, 20 ppm and 30 ppm + 4 ppm of selenium. Cadmium levels in the muscles, liver and kidneys of laying hens analysed after 60 days and those of chicks after 30 and 60 days of the experiment. Cd determinations were conducted by the method of electrothermic atomization, using an atomic absorption spectrophotometer. Body weight in laying hens was maintained at the control level, while in cocks it slightly increased in all experimental groups. In the adult birds, no mortality occurred while 0.25 - 1.11% mortality was observed in chicks. The results showed a variability in cadmium levels in hens, according to the dosage applied. These levels were high in the kidneys and liver, and lower in the muscles. A non-significant increase of cadmium level was found in the liver and kidneys of chicks after the first month of application. The addition of selenium resulted in a reduction of cadmium level in the liver and kidneys of laying hens but not in the muscles. Gross pathological and histological changes in the kidneys and liver were observed in groups fed 20 ppm and 30 ppm of cadmium.

Effect of mercury on the seminiferous epithelium of the fowl testis.

Phenylmercuric chloride was applied in three doses (5 ppm, 30 ppm Hg, and 30 ppm Hg + 4 ppm Se) via the food for 60 days. The effect of Hg with an without Se was studied histologically and the data of a shortened spermatogram were evaluated. Treatment with 30 ppm Hg resulted in hypospermia, occurrence of abnormally maturing spermatozoa, reduction of the volume of semen, and decrease in the number of spermatozoa. The dose of 5 ppm Hg only resulted in the appearance of abnormally developing cells and decreased sperm motility. The addition of Se maintained spermatogenesis and the values of semen on the control level.