Introduction: To date, there has not been any systematical and experimental research aimed at indicating the effects of Morinda officinalis How on the genital organs of male rats. \r\n', u"Objectives: To determine the effectiveness of Morinda officinalis How (MOl-I) on the genital organs of male rats, to describe the changes in histology of testicles, and evaluate the testosterone concentration in mature male rats' bloods when dosed with MOH.\r\n", u'Subjects and method: Mature and immature rats were divided into 3 groups: mature rats, castrated and non - castrated immature rats. The rats have a daily dosage of MOH: 20g/kg. The above groups of rats were euthanized after 10 days; their testicles, seminal vesicles, prostates and Cowper land were weighed; specimens of histology of testicles were made; testosterone concentration in the bloods of the mature rats was measured. Results were compared amongst experimental groups. \r\n', u'Results and conclusion: Compared with the control group, MOH (dosage 20g/kg) increased the weight of testicles, seminal vesicles, prostates, and Cowper lands (p < 0.05). In mature rats, MOH increased the testosterone concentration in the blood in comparison with the control group (p < 0.05). MOH did not change the histology of testicles, diameter of seminal ducts, but it did change the rate of seminal ducts having sperm compared with the control group and the testosterone injected group (p < 0.05). \r\n', u'
Morinda officinalis How ; Genital organs ; Male rat

Circulating antigens in rats experimentally infected with Paragonimus westermani were examined by ELISA. From a total of 22 albino rats, each fed with 25 metacercariae, blood samples were collected until 12 weeks after infection. The specific antibodies against P. westermani in the serum of an infected cat were purified by ammonium sulfate precipitation, DEAE anion-exchange chromatography and affinity chromatography serially. So-called double antibody sandwich ELISA method was used for the detection of circulationg antigens. The results were as follows: Mean value of O.D. in control sera was 0.04 (S.D.=0.04). After infection, mean O.D.(S.D) values were changed serially: 0.03(0.01) at 0.5 week(3 days), 0.55(0.50) at 1 week, 0.69(0.45) at 1.5week, 0.20(0.19) at 2 weeks and 0.13(0.10) at 2.5 weeks of infection. They returned, thereafter, to the level before infection. When 0.16(mean+3 S.D.) were considered as cut-off value, those higher than 0.16 were observed only in the sera collected between 1 and 2.5 weeks after infection. Average 8.4 immature worms (2.2 from the lungs and pleural cavities; 6.2 from muscles) were recovered in a rat at 12 weeks after infection. The fact that circulating antigens were not detected after 3 weeks of infection was considered to be caused by the formation of antigen-antibody complexs.
parasitolgy-helminth-trematoda ; Paragonimus westermani ; rat ; enzyme-linked immunosorbent assay ; antigen ; rat

A study on the ultrastructures of the prostate gland of Clonorchis sinensis was conducted. The presence of the prostate gland in this fluke has not been known up to present time. Authors observed the ejaculatory duct epithelium including its surrounding parenchyma and found the prostate gland with the help of the electron microscope. The prostate gland was consisted of numerous unicellular glands grouped around the ejaculatory duct. The individual cell was lobulated, tapering in the direction of the ejaculatory duct. The secreting ducts of the gland penetrated into the ejaculatory duct through the muscular layer and the basement membrane, and finally opened to the lumen of the ejaculatory duct. The secreting duct had single layered microtubules along the inner wall of the duct. The secretory bodies produced by the prostate gland seemed to be moved to the lumen of the ejaculatory duct through the secreting duct. The prostate gland of this fluke was less developed than that of Fasciola hepatica but the basic structures were quite similar. There were well-developed lamellae in the epithelia of all ducts concerning passage of spermatozoa from the testes to the male genital opening.
parasitology-helminth-trematoda ; Clonorchis sinensis ; electronmicroscopy ; prostatic gland ; rat ; liver

Experimentally infected rats with 50 metacercariae of Clonorchis sinensis each were treated orally with different dosages of praziquantel. About 100 rats were divided into 8 groups in each developmental week after infection (from the first to 8th week after infection) and 24 rats served as untreated controls. In each developmental week after infection, about 15 rats divided into 4groups including control group(3 to 5 rats) were used to determine for the curative activity of praziquantel against C. sinensis. The experimentally infected rats in each developmental weeks after infection received praziquantel 1 x 100 mg/kg x 3 days , 3 x 100 mg/kg x 1 day and 3 x 100 mg/kg x 2 days. The effects of the drug were evaluated by the worm recovery rates, morphological changes of the worms and the number of eggs per gram of feces (EPG) after treatment. The feces of individual rats were collected once in a week at one week before and 4 weeks after treatment, and the number of Clonorchis eggs were examined by Stoll's egg counting method. The necropsy was performed on 4 weeks after treatment. The liver and the bile ducts were examined immediately after the dissection, and all of the worms recovered from the liver immersed in warm saline solution in a small petri dish in order to observe the motility of individual worms. After that, all worms obtained from the treated and untreated control rats were fixed in 10 percent formalin solution. The whole mount specimens were prepared by Semichon's acetocarmine stain for the study of morphlogical changes. In the treatment with dosage of 1 X 100 mg/kg for 3 consecutive days, relatively low worm recovery rates were shown in the early stages of infection than those of control groups. However there was no differences of the worm recovery rates between the later stages of infection (7 to 8 weeks after infection) and control groups. In the early stages of infection, the worms recovered in the bile ducts of each treated rats showed morphologically intact as normal control groups, however in the later stages of infection the worms showed damage of their reproductive organs such as testes, seminal receptacle and ovary etc. In the treatment with dosage of 3 X100 mg/kg X 1 day, the recovery rates of the worms in all developmental weeks after infection were considerably low and some growth inhibition of the worms were also noted. The worms recovered from the bile ducts in all developmental stages were seriously damaged in their reproductive organs, such as testes, seminal receptacle, ovary, Mehlis' gland, uterus and vitelline glands etc. The hyaline degenerations were also observed on the parenchymal tissues in the dead worms. The mean EPG values in this group were markedly reduced at the first 2 weeks after treatment. However the low values of EPG were generally noted at the 3rd to 4th week after treatment. On the other hand, in the treatment with dosage of 3 X 100 mg/kg X 2 days, no more the living worms was recovered in all developmental stages of Clonorchis . The dead worms recovered from the bile ducts were so seriously damaged that the morphological changes could not be observed. The mean EPG values in this group were markedly reduced during the first 2 weeks after treatment. At the 3rd week after treatment EPG value became negative in the most of all treated groups. No more the Clonorchis eggs were detected at the 4th week after infection, but only a very small numbers of eggs were found by the concentration method. From the above results, it is obvious that praziquantel exhibits a high degree of activity against Clonorchis sinensis in the rats, with no apparent differences in the efficacy against each developmental stage.
parasitology-helminth-trematoda ; Clonorchis sinensis ; chemotherapy-praziquantel ; rat ; praziquantel

The metacercariae of an echinostomatid fluke were detected from a freshwater fish, Odontobutis obscura interrupta caught from the Seom river system, Wonseong-gun, Kangwon-do, and experimenally infected into rats to obtain the adult worms for the species identification. A total of 32 metacercariae was detected from 10 fishes (27.8 percent) out of 36 O. obscura interrupta caught from the river. The average size of metacercariae was 153.4 x 149.0 micrometer. Also, it was uniquely specific that thickened membrane was formed around the metacercarial cyst wall. The rats orally infected with those metacercariae were sacrificed 20 days after infection to get the adult worms. The mean length and width of the adult worms were 0.75 cm and 0.13 cm, respectively. The number of collar spines on circumoral disk was 26 to 28, and the end group spines at lateral sides of the oral sucker were 4 on each side. The echinostomatid flukes observed in this study were all identified as Echinostoma hortense according to the morphologies of the cirrus sac, ovary, vitellaria and testes of the adult worms and the shape of eggs. On the other hand, O. obscura interrupta is one of the fresh-water fish that are preferably eaten raw by the rural inhabitants. Although no human case of E. hortense infection by eating O. obscura interrupta has been experienced yet, the possibility is strongly suggested in this study.
parasitology-helminth-trematoda ; Echinostoma hortense ; metacercariae ; Odontobutis obscura interrupta ; rat

The growth and development of Pygidiopsis summa were studied in experimental rats and mice, and a special reference was given to its morphological characters differed from the type species, P. genata. The metacercariae were obtained from young mullets (Mugil sp.), and total 21 rats and mice infected each with 1,000 metacercariae. Worms of various ages of infection, from 3 to 28 days, were subjected to a microscopic observation. The worms grew rapidly and remarkably in size up to 10 days of infection, to become 0.53-0.82 mm long and 0.31-0.39 mm wide, but nearly stopped the growth thereafter. Their genital organs developed more rapidly and fully matured within 3-5 days. At 3 days several eggs were found in uterus. The presence of two groups of small spines, 5-6 on the right and 7-9 on the left side of the genital apparatus, was a new finding in this study and considered a distinct character of P. summa. The morphology of ventral sucker and intestinal ceca was also different from P. genata. This study confirms the validity of the species, P. summa.
parasitology-helminth-trematoda ; Pygidiopsis summa ; morphology ; development ; rat

The present study attempted to demonstrate an acquired immunity against Clonorchis sinensis in albino rat. Three separate experiments were carried out to determine acquired resistance developed by stimulating procedure followed by challenging infection with metacercariae. Acquired resistance was evaluated by the rate of recovery or the average number of flukes recovered from the liver of challenged albino rats, compared with the controls. In drder to demonstrate the rate of recovery of the fluke, three experimental groups of rats were challenged with 50 metacercariae per rat- 7,15 and 30 days after single injection of worm extract. The recovery rate was ranged from 33.2% to 38.0% in experimental group and their control group harbored from 37.8% to 42.6%. No significant difference was found on statistical analysis. In experimental groups received two immunizing injections with worm extract followed by challenging infection of metacercariae. Statistically significant difference was recovered between experimentals and controls. It was noted that reduction of the recovery rate was prominent in Group 5 and 6, which were challenged 15 and 30 days after two stimulating injections. From the third experiment which was consisted of single immunizing infection with 20 metacercariae followed by challenging infection with 30 metacercariae, no significant reduction was found between experimental rats and their controls. The number of recovered worms ranged from 16.2 to 18.5 worms in experimental group, while that of control group ranged from 18.9 to 19.8 worms. The evidence of delayed hypersensitivity reaction was observed in the groups with acquired immunity developed rats, by histopathological study of host hepatic tissue.
parasitology-helminth-trematoda ; Clonorchis sinensis ; immunology ; rat ; histology

This study was carried out to observe the growth and development of Fibricola seoulensis in experimentally infected rats and mice. The metacercariae were obtained from naturally infected Natrix tigrina lateralis which were collected in Hoengseong Gun, Gangweon Do, in August 1982. The results were summarized as follows. Growth and development of worm were not different between the rat and mouse. Body growth was attained within a week in both hosts. The testes differentiated first on the 2nd day after infection, and then ovary on the 3rd day, vitelline follicles on the 4th day, vitelline reservoir on the 5th day. A few eggs appeared in uterus on the 5th day and in feces on the 6th day. The body length grew almost linearly for the first 7 days after infection. The growth of posterior body was more remarkable, and the ratio of posterior body length to that of anterior body increased to 1.099 until 4 weeks after infection. The worms of 4weeks age in rats measured 1.10-1.92 mm long and 0.511 - 0.696 mm wide. The morphological characteristics of adult worms were identical to the original description of F. seoulensis, though dimensions varied in wider range. The worms were recovered from the rats 12.5% on the day after infecion, and the rate ranged 21.0-59.0% up to 6th day. One week after infection, the rates were 42.6%, 60.9% and 43.9% respectively by the metacercarial group of 200, 1,000 and 2,000 and the rates decreased to 16.2%, 29.1% and 3.1% respectively by the group on the 4th week after infection. Most of the worms were recovered from duodenum, and a part of worms were found in jejunum or ileum in heavily infected rats. The worms of 23.5-63.5% were recovered from mice from 3 to 10 days after infection. A great majority of them was found in duodenum, too.
parasitology-helminth-trematoda ; Fibricola seoulensis ; development ; biology ; rat

A histopathological study was carried out on the duodenum of mice and rats experimentally infected by F. seoulensis. Each mouse was infected wit 500 metacercariae and killed after 1, 2, 3 days, 1 and 2 weeks from infection. Each rat was given 1,000 metacercariae and was examined after 1, 2, and 4 weeks from infection. The duodenal tissue sections of mice and rats were stained with hematoxylin and eosin, and PAS stained for the rats of 1 week group. The pathological findings are summarized as below. There were no differences in mucosal findings between the mice and the rats, adn between the location of duodenum, 1 and 5 cm distal to the pylorus. Each worm embraced a villus exclusively with its foliate forebody which was inserted into the intervillous spaces. The fluke pinched villous epithelia using its oral and ventral suckers. The tribocytic organ destroyed the villous epithelia deeply up to the stroma after 3 days from infection. Apparent villous changes were observed in the mice after 3 days from infection. Villous changes were shortening, widening, blunting or fusion. The villous stroma showed edema, microscopic hemorrhage, capillary congestion, dilatation of lymphatics and inflammatory cell infiltration. The cells were lymphocytes, plasma cells, eosinophils and giant cells. Rarely submucosal and transmural inflammation was encountered.
parasitology-helminth-trematoda ; Fibricola seoulensis ; histology ; pathology ; intestine ; rat

The worm development and egg laying pattern of Echinostoma hortense(Trematoda: Echinostomatidae) were studied in albino rats and the brief clinical course was observed in human volunteers. A total of 21 rats were infected with 20-69 metecercariae each and two humans were with 7 and 27 metacercariae, which were collected from loaches. For recovery of worms, the rats were sacrificed at irregular intervals from the 6th to 150th day after infection and the human volunteers were treated with praziquantel and purged with magnesium salt on the 26-27th day. The stools of the rats and humans were examined for the eggs. The results were as follows: The worm recovery rate from the rats was not affected by the increase of infection time but varied individually; 9.1-50.0% (31.1% in average). From humans, 14.3% and 37.0% (32.4% in average) of challenged were recovered. In the rats, it was revealed that the worms rapidly grew for the first 14 days to become 7.59 mm in average length and 1.17 mm in average width but the growth became much slower thereafer until the 150th day; 7.95 mm in length on the 21th day, 9.04 mm on the 28th day, 10.21 mm on the 49th day and 12.62 mm on the 150th day. During the early stage of infection, the growth of genital organs(male or female) was expressed as sigmoid curves whereas non-genital organs(such as suckers) was simply as straight lines. The prepatent period of this fluke was 10-12 days in the rats and 16-17 days in men. After the start of oviposition, the egg production by the worms remarkably increased, reached maximum on the 32-33th day, followed by decrease thereafter. The maximum value of E.P.G./worm was 390. The major subjective symptoms in human volunteers were abdominal pain and diarrhea during the early stage of infection. The results show that human is as susceptible as the rats to E. hortense infection and the amount of egg production in the rats is greatly affected by the age of worms.
parasitology-helminth-trematoda ; Echinostoma hortense ; rat ; biology ; metacercaria