• Title/Summary/Keyword: spermatogenesis

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Outcome of Gonadotropin Therapy for Infertile Men with Hypogonadotropic Hypogonadism (저성선자극호르몬 성선저하증 (Hypogonadotropic Hypogonadism)으로 진단된 남성불임 환자에서 성선자극호르몬 (Gonadotropin) 치료가 정자형성 및 임신에 미치는 영향)

  • Joo, Young-Min;Kim, Tae-Hong;Seo, Ju-Tae
    • Clinical and Experimental Reproductive Medicine
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    • v.36 no.3
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    • pp.219-224
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    • 2009
  • Objective: Hypogonadotropic hypogonadism (HH) is an uncommon cause of male infertility. We investigated the outcome of gonadotropin therapy for restoring fertility and pregnancy outcomes in patients with HH. Methods: Medical charts of 10 infertile male patients with HH treated with gonadotropin were reviewed. Initial testicular volume were estimated. Semen analysis parameters (semen volume, sperm counts, motility), serum leutenizing hormone (LH), follicle stimulating hormone (FSH), total testosterone were determined before and after human chorionic gonadotropin/human menopausal gonadotropin (hCG/hMG) treatment. Differences were analyzed statistically. Results: Of 10 patients, 7 (70%) succeed at pregnancy (nature pregnancy in 4). Semen analysis parameters, serum FSH, and testosterone were increased significantly after treatment. The population was stratified according to initial testicular volume into a small testis subset (testicular volume less than 10 cc in 4) and a large testis subset (testicular volume 10 cc or greater in 6). Semen analysis parameters and serum testosterone were increased significantly after treatment in large testis subset. Conclusion: Infertile men with HH initiate and maintain spermatogenesis with gonadotropin (hCG/hMG alone or combined) therapy, thus gonadotropin therapy is good choice in infertile men with HH.

Identification of genes involved in inbreeding depression of reproduction in Langshan chickens

  • Xue, Qian;Li, Guohui;Cao, Yuxia;Yin, Jianmei;Zhu, Yunfen;Zhang, Huiyong;Zhou, Chenghao;Shen, Haiyu;Dou, Xinhong;Su, Yijun;Wang, Kehua;Zou, Jianmin;Han, Wei
    • Animal Bioscience
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    • v.34 no.6
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    • pp.975-984
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    • 2021
  • Objective: Inbreeding depression of reproduction is a major concern in the conservation of native chicken genetic resources. Here, based on the successful development of strongly inbred (Sinb) and weakly inbred (Winb) Langshan chickens, we aimed to evaluate inbreeding effects on reproductive traits and identify candidate genes involved in inbreeding depression of reproduction in Langshan chickens. Methods: A two-sample t-test was performed to estimate the differences in phenotypic values of reproductive traits between Sinb and Winb chicken groups. Three healthy chickens with reproductive trait values around the group mean values were selected from each of the groups. Differences in ovarian and hypothalamus transcriptomes between the two groups of chickens were analyzed by RNA sequencing (RNA-Seq). Results: The Sinb chicken group showed an obvious inbreeding depression in reproduction, especially for traits of age at the first egg and egg number at 300 days (p<0.01). Furthermore, 68 and 618 differentially expressed genes (DEGs) were obtained in the hypothalamus and ovary between the two chicken groups, respectively. In the hypothalamus, DEGs were mainly enriched in the pathways related to vitamin metabolism, signal transduction and development of the reproductive system, such as the riboflavin metabolism, Wnt signaling pathway, extracellular matrix-receptor interaction and focal adhesion pathways, including stimulated by retinoic acid 6, serpin family F member 1, secreted frizzled related protein 2, Wnt family member 6, and frizzled class receptor 4 genes. In the ovary, DEGs were significantly enriched in pathways associated with basic metabolism, including amino acid metabolism, oxidative phosphorylation, and glycosaminoglycan degradation. A series of key DEGs involved in folate biosynthesis (gamma-glutamyl hydrolase, guanosine triphosphate cyclohydrolase 1), oocyte meiosis and ovarian function (cytoplasmic polyadenylation element binding protein 1, structural maintenance of chromosomes 1B, and speedy/RINGO cell cycle regulator family member A), spermatogenesis and male fertility (prostaglandin D2 synthase 21 kDa), Mov10 RISC complex RNA helicase like 1, and deuterosome assembly protein 1) were identified, and these may play important roles in inbreeding depression in reproduction. Conclusion: The results improve our understanding of the regulatory mechanisms underlying inbreeding depression in chicken reproduction and provide a theoretical basis for the conservation of species resources.

Protective effects of Korean Red Ginseng against sub-acute immobilization stress-induced testicular damage in experimental rats

  • Lee, Sang-Ho;Choi, Kyung-Hwa;Cha, Kyu-Min;Hwang, Seock-Yeon;Park, Un-Kyu;Jeong, Min-Sik;Hong, Jae-Yup;Han, Chang-Kyun;In, Gyo;Kopalli, Spandana Rajendra;Kim, Si-Kwan
    • Journal of Ginseng Research
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    • v.43 no.1
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    • pp.125-134
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    • 2019
  • Background: Excessive stress causes varied physiological and psychological disorders including male reproductive problems. Here, we attempted to investigate the protective effects of Korean Red Ginseng (Panax ginseng Meyer; KRG) against sub-acute immobilization stress-induced testicular damage in experimental rats. Methods: Male rats (age, 4 wk; weight, 60-70 g) were divided into four groups (n = 8 in each group): normal control group, immobilization control group, immobilization group treated with 100 mg/kg of KRG daily, and immobilization group treated with 200 mg/kg of KRG daily. Normal control and immobilization control groups received vehicle only. KRG (100 mg/kg and 200 mg/kg) was mixed in the standard diet powder and fed daily for 6 mo. Parameters such as organ weight, blood chemistry, sperm kinematic values, and expression levels of testicular-related molecules were measured using commercially available kits, Western blotting, and reverse transcription polymerase chain reaction. Results: Data revealed that KRG restored the altered testis and epididymis weight in immobilization stress-induced rats significantly (p < 0.05). Further, KRG ameliorated the altered blood chemistry and sperm kinematic values when compared with the immobilization control group and attenuated the altered expression levels of spermatogenesis-related proteins (nectin-2, cAMP responsive element binding protein 1, and inhibin-${\alpha}$), sex hormone receptors (androgen receptor, luteinizing hormone receptor, and follicle-stimulating hormone receptor), and antioxidant-related enzymes (glutathione S-transferase m5, peroxiredoxin-4, and glutathione peroxidase 4) significantly in the testes of immobilization stress-induced rats. Conclusion: KRG protected immobilization stress-induced testicular damage and fertility factors in rats, thereby indicating its potential in the treatment of stress-related male sterility.

Novel method of histopathological analysis after testicular sperm extraction in patients with nonobstructive and obstructive azoospermia

  • Cito, Gianmartin;Coccia, Maria Elisabetta;Picone, Rita;Nesi, Gabriella;Cocci, Andrea;Dabizzi, Sara;Garaffa, Giulio;Fucci, Rossella;Falcone, Patrizia;Bertocci, Francesco;Santi, Raffaella;Criscuoli, Luciana;Serni, Sergio;Carini, Marco;Natali, Alessandro
    • Clinical and Experimental Reproductive Medicine
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    • v.45 no.4
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    • pp.170-176
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    • 2018
  • Objective: To assess whether the "testicular pool" could be used for histological analysis and whether it gave more accurate information than the standard testicular biopsy. Methods: Between January 2017 and March 2018, this single-center prospective study included 60 azoospermic men undergoing conventional bilateral testicular sperm extraction. Six samples were excised from each testicle and transferred to an embryologist. One additional biopsy was randomly taken from each testis for a histological analysis. After processing, the testicular pool was also sent for a histological analysis, which showed normal spermatogenesis (NS), hypospermatogenesis (HYPO), maturation arrest (MA), Sertoli cell-only syndrome (SCOS), and tubular atrophy (TA). Results: Twenty of the 60 patients (33.3%) had obstructive azoospermia (OA), while the remaining 40 (66.6%) had nonobstructive azoospermia. Their mean age was 40.5 years. All patients with OA had previously undergone unsuccessful testicular fine-needle aspiration. Successful sperm retrieval (SSR) occurred in 93.3% of patients. Histological analysis of the testicular biopsy revealed NS in 12 patients (20%), HYPO and TA in 28 patients (46.6%), MA in eight patients (13.3%), and SCOS in 12 patients (20%). The testicular pool analysis showed NS in 12 patients (20%), HYPO and TA in 44 patients (73.3%), MA in four patients (6.6%), and SCOS in no patients. In four patients with MA (6.6% of the total sample) and 12 patients with SCOS (20% of the total sample) according to the standard testicular biopsy, the embryologist found SSR with cryopreservation. Overall, in 44 patients (73.3%), the testicular pool analysis confirmed the histological findings of the standard testicular biopsy. In the 16 cases (26.6%) with a discrepancy between the single-biopsy histological findings and SSR, the testicular pool analysis confirmed the embryological data on SSR. Conclusion: The testicular pool proved to be easily analyzable, practical, manageable, and more accurate for predicting sperm retrieval than standard testicular biopsy.

Effects of Fructus Amomi Amari, Eucommiae Cortex, Bombyx Batryticatus Extract on Improving Symptoms of Late-onset Hypogonadism (익지인(益智仁), 두충(杜沖), 백강잠(白殭蠶) 혼합추출물이 남성갱년기 증상 개선에 미치는 영향)

  • Park, Sun Young;Ahn, Sang Hyun;Kim, Ho Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.2
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    • pp.89-101
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    • 2019
  • In recent times, the number of men with late-onset hypogonadism has increased, and interest on this topic has also increased. This study was conducted to investigate effects of the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus on improve late-onset hypogonadism. The experimental subjects consisted of three groups: a control group consisting of 8-week-old male ICR mice that had undergone no treatment, an aging-elicited group (AE group) consisting of 50-week-old ICR male mice that had undergone no treatment, and a Mixed herbal extract treatment group (MT group) consisting of 50-week-old ICR male mice that had undergone the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus treatment (0.1 g/kg/day) for 6 months. After the experiment, the mice from all the experimental groups were dissected, and they were analyzed through histochemical and immunohistochemical methods. The mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus reduces aging-induced cell damage and oxidative stress and increases the secretion of serotonin and B-endorphin in aged mice, and promotes spermatogenesis in seminiferous tubules and reduces apoptosis and oxidative stress, and increases androgen receptor, $17{\beta}-HSD$ and GnRH, increases the ratio of smooth muscle to collagen fibers in the corpus cavernosum, increases eNOS, decreases PDE-5 and oxidative stress in aged mice, so it improves depression, reproductive, sexual problems caused by Late-onset hypogonadism. the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus inhibits the induction of osteoporosis by increasing decreased bone matrix distribution due to aging, increasing the activities of OPC and OPN, which are produced in osteoblasts, and decreasing RANKL, MMP-3 activity, increasing OPG activity. It also reduces muscle damage, oxidative stress, inflammation and apoptosis of muscle tissue, and increases Myo-D in the sartorius muscle of aged mice for improving muscle atrophy caused by by Late-onset hypogonadism.

Testicular Development and Serum Levels of Gonadal Steroids Hormone during the Annual Reproductive Cycle of the Male Koran Dark Sleeper, Odontobutis platycephala (Iwata et Jeon) (동사리, Odontobutis platycephala (Iwata et jeon) 수컷의 생식주기에 따른 정소 발달과 혈중 생식소 스테로이드의 변화)

  • 이원교;양석우
    • Journal of Aquaculture
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    • v.11 no.4
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    • pp.475-485
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    • 1998
  • To clarify annual reproductive cycle of Koran dark sleeper, odontobutis platycephala, we examined the seasonal changes of gonadosomatic index(GSI), testicular development stages and sex steroid hormones in blood from December 1995 to November 1997. Testis was podlike shape from July to October, and tadpole-like shape from November because of its expanded posterior part. GSI was 0.14~0.18 from July to September and increased to $0.43{\pm}0.04$ in October and then was not changed significantly until February. GSI was reincreased to $0.52{\pm}0.09$ from March and then was kept at similer levels until May, but fell down to $0.28{\pm}0.05$ in June. As results of histological observation, testis was divided into 3 parts(anterior, boundary, posterior) in the development progress of germ cells. In July, the testis was composed of only spermatogonia without seminiferous tubules in most fishes. In the anterior part of testis, the ferquency of spermatogenesis stage seminiferous tubules appearing in August was more than 80% from September to December. decreased gradually from January to March and drastically in April, and then disappeared in June. The frequency of spermiogenesis stage seminiferous tubules appearing in December, increased gradually from January to March and drastically to 80% in April, and reached to 90% the highest levels of the year in June. Post-spawning stage seminiferous tubules did not appear throughout the year. The frequency of spermatogonia was 100% and 65% in July and August, and less than 20% in the rest period of the year. In the boundary part, the frequency of spermatogenesis stage seminiferous tubules appearing in August increased from September and reached to 82% in November, decreased from December, adn disappeared in March. The frequency of spermiogenesis stage seminiferous tubules appearing in November was less than 18% until February, and increased to 29%~57% from March to June. The frequency of post-spawning stage seminiferous tubules appeared 12%~25% only from March to June. The frequency of spermatogonia was 100% in July, decreased to 85% in August and 10% in November, and increased gradually from December to 50% in April, and decreased again from May to June. In the posterior part, seminiferous tubules with some seminiferous tubules increased drastically 80%~85% in August and September, decreased drastically from October to November and remained below 10% until February, and disappeared after March. The frequency of spermiogenesis stage seminiferous tubules appearing in August increased sharply from October and reached to 75% in November. decreased to 15% in December and no significant changes until March, and disappeared after April. The frequency of post-spawning stage seminiferous tubules appearing very early in November increased to 82% in December and 85%~95% until June. The frequency of spermatogonia was 100% in July, decreased drastically to 15% in August, disappeared from October to Mrch, but reappeared from April and kept at less than 10% until June. The blood level of testosterone (T) increrased gradually from August was $0.61{\pm}0.09 ng/m\ell$ in November, increrased drastically to $3.99{\pm}1.22 ng/m\ell$ in December and maintained at in similar level until March, and decreased to $0.25{\pm}0.14 ng/m{\ell} ~ 0.17{\pm}0.13ng/m{\ell}$ in April and May and no significant changes until July (P<0.05). The blood level of 17, 20 -dihydroxy-4-pregnen-3-one $ng/m{\ell}$in the rest of year without significant changes(P<0.05). Taken together these results, the germ cell development of testis progressed in the order of posterior, boundary, anterior part during annual reproductive cycle in Korean dark sleeper. The testicular cycle of Korean dark sleeper was as follows. The anterior part of testis : i.e. spermatogonial proliferation period (July), early maturation period (from August to November), mid maturation period (from December to March), late maturation period (from April to May) and functional maturation period (June) were elucidated. The boundary of testis, i.e. spermatogonial proliferation period (July), early maturation period (from August to October), mid maturation period (from November to February) and the coexistence period of late maturation, functional maturation and post-spawn (from March to June) were elucidated. The posterior of testis, i.e. spermatogonial proliferation period (July), mid maturation period (from August ot September), late maturation period (October), functional maturation period (November) and post-spawn period (from December to June) were elucidated. It was showed that the changes of sex steroid hormone in blood played a important roles in the annual reproductive cycle of Korean dark sleeper.

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Effects of Maturation Duration and Activation Treatments on Activation and Development of Porcine Follicular Oocytes (돼지 난모세포의 단위발생에 있어서 성숙시간과 활성화 처리가 활성화와 발달에 미치는 영향)

  • Kim H. J.;Choi S. H.;Han M. H.;Son D. S.;Ryu I. S.;Kim I. C.;Lee J. H.;Kim I. H.;Im K. S.;Cho S. R.
    • Journal of Embryo Transfer
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    • v.20 no.1
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    • pp.25-33
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    • 2005
  • This study is a part of research that development of effective genetic resources preservation system using the in vitro spermatogenesis, in vitro insemination and culture system. We aimed for establishment of in vitro culture system with in vitro activated porcine oocytes. The porcine oocytes were matured for 48 hours in $TCM199+10\%$ FCS and activated with $7\%$ ethanol. The activated oocytes were cultured for 7 days in $TCM199+10\%$ FCS or $NCSU23+0.4\%$ BSA medium. The activated oocytes were not developed to the blastocyst stage in $TCM199+10\%$ FCS medium. However in $NCSU23+0.4\%$ medium, those were developed to blastocyst with $3\%$ of treated oocytes. We extended maturation duration of porcine follicular oocytes fur 48, 52, 56, 60, 64, 68, and 72 hours and activated with $7\%$ ethanol and cultured using $NCSU23+0.4\%$ BSA medium. The six percents of activated oocytes were developed to blastocyst in 48 hours and $10\%$ in 52 hours with comparatively low rates suggested to be not fully activated by regenerated MPF. Maturation durations from 56 hours to 68 hours supported to develop upto $11.9\~18.3\%$ of blastocysts. However the developmental rate was declined to $7.2\%$ at 72 hours of maturation duration because of cytoplasmic deterioration. The assumed time window for activation will be $56\~68$ hours of maturation duration. When the matured oocytes were activated with electric pulse of 1, 1.2, 1.4, 1.6, 1.8 and 2.0kV/cm for $80{\mu}s$, although appling the electric current once was not enough for activation, appling twice with 1.6kV/cm for $80{\mu}s$ was shown the highest developmental rate with $11.3\%$. When those were compared with activating methods, $15.7%$ of blastocyst rate was obtained in the $7\%$ ethanol. That was higher than those in electric pulse with $9.5\%$ and calcium ionophore method with $5.8\%$. In this experimental condition, the $7\%$ ethanol treatment was the most effective method for activating porcine oocytes.

Effects of Bisphenol and Octylphenol on TM3 Cell : Expression of Cytochrome P450scc and Estrogen Receptor $\alpha$ mRNA (Bisphenol과 Octylphenol이 TM3 세포에 미치는 영향: Cytochrome P450scc와 Estrogen Receptor $\alpha$ 유전자의 발현)

  • 이호준;김묘경;강희규;김동훈;한성원;고덕성
    • Development and Reproduction
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    • v.4 no.2
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    • pp.215-220
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    • 2000
  • Most of endocrine disrupters (EDs) have been reported to exhibit estrogenic or anti-androgenic activity and thereby may disrupt reproductive development in human or wildlife. This study was performed to investigate the effects of estrogen (E$_2$), bisphenol (BP) and octylphenol (OP) on the mouse Leydig cell line (TM3). TM3 originated from testis of 11~13-daly-old BALB/c nu/+ mice was cultured in DMEM supplemented with 10% FBS alone or medium with estrogen (E$_2$), bisphenol (BP) and octylphenol (OP; 1 pM, 1 nM, 1 $\mu$M, 1 mM, respectively) for 48 hours. After culture, total cell number and viability were assessed by heamocyto-meter and trypan blue stain. Expression of cytochrome P450scc (CYPscc) mRNA whose product is involved in steroid hormone biosynthesis and estrogen receptor $\alpha$(ER $\alpha$) mRNA were detected by RT-PCR. As a result, treatment of TM3 with E$_2$, BP and OP(1 mM, respectively) significantly decreased the viability but not all of groups as high as 1 $\mu$M. Exposure of TM3 to OP significantly reduced the total cell number but not E$_2$ or BP. The expression of CYPscc mRNA was slightly reduced in BP (1 nM, 1 $\mu$M) and significantly decreased in OP (1 nM, 1 $\mu$M) treated TM3, except E$_2$ group. But the expression of ER $\alpha$ mRNA was sightly increased in all treated groups. In conclusion, BP and OP (high concentration) might inhibit steroidogenesis by decreasing the CYPscc mRNA expression in the mouse testis. These results suggest that BP and OP might impair spermatogenesis and subsequently disturb testicular function.

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Experimental Studies on Lead Toxicity in Domestic II. Histopathology (고양이의 납중독에 관한 실험적 연구 2. 조직병리학적 소견)

  • Hong Soon-Ho;Han Hong Ryul
    • Journal of Veterinary Clinics
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    • v.11 no.1
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    • pp.485-505
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    • 1994
  • Lead toxicity was evaluated in forty-five cats on a balanced diet, treated with 0(control), 10, 100(low), 1, 000, 2, 000 and 4, 000(high)ppm of lead acetate orally on a body weight basis. The objectives were to describe the gross and histopathologic changes and to demonstrate what tissue lead concentrations correlate with the known dosages of lead. In subclinical lead toxicity, greater than 80% of the absorbed lead was deposited in the bone, whereas in more acute lead toxicity, 42% of absorbed lead was deposited in the bone and 36% and 20% of absorbed lead was deposited in the kidneys and in the liver, respectively. No gross lesions were found in the nervous system. Yellow-brown colored livers appear to be associated with lead toxicity. Neuronal necrosis in the cerebrum was the most predominant histopathologic finding. Astrocytic proliferation in the cerebral gray matter was observed in 1 high dose cat. Gliosis was noted in the cerebral cortex of 6 high dose cats. Two high dose cats had demyelination in the deepest layer of the cortical gray matter of the cerebrum. Extravasation of red cells and cavitation around the vessels were found in the cerebrum of 1 high dose cat. Six high dose cats had degeneration of Purkinje cells in the cerebellum. The microscopic findings in the peripheral nerves were ambiguous. In more acute toxicity, the cats had lead inclusions in the epithelial cells of proximal tubules of the kidneys of 7 cats and hepatocytes of the liver of S cats. These inclusions could be seen wlth H&E, but were more prominent with orcein staining. Two high dose cats had granulomas and connective tissue hyperplasia between tubules of the kidneys. Periportal hepatocyte vacuolization was observed in the liver of 22 cats. Vacuolization of seminiferous tubules and a reduced number of spermatogonia(indicative of reduced spermatogenesis) were found in the testis of 5 treated cats. Cystic ovaries were observed in 3 high dose cats and poor development of oogonia was found in 2 cats. The diagnosis of lead toxicity in cats can be suspected on the basis of the histopathologic lesions described, and can be of value in contributing to a diagnosis. A reliable diagnosis of lead poisoning can be helped utilizing tissue lead analysis(post molten)

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GAMETOGENESIS AND EARLY DEVELOPMENT OF LINUPARUS TRIGONUS(VON SIEBOLD) (펄닭새우 생식세포형성과정 및 초기발생)

  • KIM Chang-Hyeon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.10 no.2
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    • pp.71-96
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    • 1977
  • Early development Linuparus trigonus(von Siebold) has been studied based on the samples collected monthly in Je-ju Island, Korea from February, 1975 to January, 1977. Gametogenesis, reproductive cycle, embryonic development were investigated by histological mettled, and morphological description was made on the first phyllosoma larva which reared in the laboratory. Testis is composed of two tubular duct which are symmetrical with H-shaped appearance. Outer layer of testis is of fibrous connective tissue capsule. In the lumen there is a convoluted seminiferous tubule with interstitial tissue. Ovary is a pair of symmetrical blind tubular lobes, and the midportions are connected each other. The ovary consists of a couple of ovarian sacs partitioned by two-layered connective tissue fibers. Proliferation of spermatogonia are observed all the year around on the germinal epithelium of seminiferous tubule. Partial spermatogenesis is always in progress, and the spermatozoa appear all the year around in the tubules. Nutrition of early oogonia is supplied by fibrous mesenchyme which is abundantly distributed in ovarian sacs. Oocytes grow and couplete maturation divisions in the follicle layers. They finally develop into mature ova before spawning. Reproductive cycle is classified into four successive stages; multiplication stage from September to December, growing stage from January to March, maturation division stage from April to May and mature stage from June to August. Spawning takes place from May to August with peak spawning from Into July to early August. Cleavage type is superficial. Blastopore is formed in blasto-disc region which is proliferation of blastoderm cells. Germinal layers are also derived from tile region. Mesoderm formation is originated from endodermal cells which are formed front the blasto-disc region. The endodermal cells are separated by the process of delamination from yolk sac and take part in the formation of the mid-gut. Morphological characteristics of first phyllosoma larva are different from the larvae of other Palinurid and Scyllarid species.

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