Evaluation of conservation of endangered species through somatic cell nuclear technology / 대한수의학회지

The number of wild animal species is gradually decreasing due to poaching, hunting and habitat loss. While several endangered animal species have been successfully preserved at the zoo, assisted reproductive technology (ART) must be applied to restore wild animals. In the case of critically endangered animals, somatic cell cloning is considered the most appropriate method of ART. Somatic cell cloning can be beneficial for the reproduction of endangered species with limited female populations. However, gene and cell banks, and understanding of reproductive physiology and optimization of ART for wild animals are urgently required for further activation of artificial reproduction of endangered species, which enlarges its application and maintains biodiversity. Care should also be taken to consider ethical and legal issues associated with somatic cell cloning for conservation of endangered animals.

Visceral Hypersensitivity and Altered Colonic Motility in Type 2 Diabetic Rat

BACKGROUND/AIMS: Abnormal visceral sensitivity and disordered motility are common in patients with diabetes mellitus. The purpose of the present study was to investigate whether visceral sensation and bowel motility were altered in a rat model of type 2 diabetes mellitus accompanied by weight loss. METHODS: A type 2 diabetic rat model in adulthood was developed by administrating streptozotocin (STZ; 90 mg/kg, i.p.) to neonatal rats. Eight weeks after STZ administration, rats with blood glucose level of 200 mg/dL or higher were selected and used as diabetic group (n = 35) in this study. Abdominal withdrawal reflex and arterial pulse rate were measured to examine visceral nociception induced by colorectal distension (0.1-1.0 mL). The amplitude, frequency, and area under the curve (AUC) of spontaneous phasic contractions of colonic circular muscles were recorded in vitro to examine colonic motility. RESULTS: STZ-treated diabetic rats gained significantly less weight for 8 weeks than control (P < 0.01). Forty-eight percent of the diabetic rats showed enhanced visceral nociceptive response to colorectal distension. Diabetic rats did not differ from control rats in colorectal compliance. However, the frequency and AUC, not the amplitude, of colonic spontaneous contraction in vitro was significantly decreased in diabetic rats compared to control rats (P < 0.01 in frequency and P < 0.05 in AUC). CONCLUSIONS: These results demonstrate visceral hypersensitivity and colonic dysmotility in a rat model of type 2 diabetes mellitus accompanied by weight loss.

1918 Influenza Pandemic in Korea: A Review on Dr. Schofield' Article / 의사학

The article "Pandemic influenza in Korea with special references to its etiology," published in JAMA in April, 1919 by Dr. Frank William Schofield, is a valuable material reflecting the influenza pandemic situation in 1918 in Korea. It contains the case reports of influenza infected patients and the results of the bacteriological experiments. Dr. Schofield worked as a bacteriology professor in Severance Union Medical College in Seoul from 1916 to 1920. His academic activities are lesser-known than the role of contributor of Korean independent movement. However, he was a remarkable veterinarian and scientist. According to Dr. Schofield, the number of Influenza infected population in Korea in 1918 was supposed to be 4,000,000 to 8,000,000, which corresponds with other resources(6.7 per 1,000 in Gangwon province). Considering the cases which were not registered as influenza infection by misdiagnosis of pneumonia complication the sum should be higher. However, the estimated crude influenza death rate from the reports by the Japanese colonial government was only 2.38(per 1,000). Dr. Schofield and his colleague tried to culture "Pfeiffer Bacillus" from the sputum and blood specimens of patients showing typical influenza symptoms. The bacterium was mistakenly considered as the influenza agent till the virological nature of influenza was discovered in the 1930s. From the results of his study he seemed to agree that "filterable virus" was the influenza agent and the secondary infection of the bacillus caused respiratory symptoms. He also reported on the influenza vaccination during the epidemics. Dr. Schofield's article confirms that the damage caused by the influenza outbreak in Korea was as great as in other Asian countries or even worse. It also gives information about the researches and education on the etiology and vaccination of influenza based on the germ theory in the medical colleges in Korea, which adopted the western medical educational system in the early 20th century.

Alteration of nitrergic neuromuscular transmission as a result of acute experimental colitis in rat

Nitric oxide (NO) is a non-adrenergic, non-cholinergic neurotransmitter found in the enteric nervous system that plays a role in a variety of enteropathies, including inflammatory bowel disease. Alteration of nitrergic neurons has been reported to be dependent on the manner by which inflammation is caused. However, this observed alteration has not been reported with acetic acid-induced colitis. Therefore, the purpose of the current study was to investigate changes in nitrergic neuromuscular transmission in experimental colitis in a rat model. Distal colitis was induced by intracolonic administration of 4% acetic acid in the rat. Animals were sacrificed at 4 h and 48 h postacetic acid treatment. Myeloperoxidase activity was significantly increased in the acetic acid-treated groups. However, the response to 60 mM KCl was not significantly different in the three groups studied. The amplitude of phasic contractions was increased by Nomega-nitro-L-arginine methyl ester (L-NAME) in the normal control group, but not in the acetic acid-treated groups. Spontaneous contractions disappeared during electrical field stimulation (EFS) in normal group. However, for the colitis groups, these contractions initially disappeared, and then reappeared during EFS. Moreover, the observed disappearance was diminished by L-NAME; this suggests that these responses were NO-mediated. In addition, the number of NADPH-diaphorase positive nerve cell bodies, in the myenteric plexus, was not altered in the distal colon; whereas the area of NADPH-diaphorase positive fibers, in the circular muscle layer, was decreased in the acetic acidtreated groups. These results suggest that NO-mediated inhibitory neural input, to the circular muscle, was decreased in the acetic acid-treated groups.

Electroacupuncture ameliorates experimental colitis induced by acetic acid in rat

The effect of electroacupuncture (EA) on experimental colitis was investigated in Sprague-Dawley rats. Colitis was induced by intracolonic instillation of 4% acetic acid. EA (2 Hz, 0.05 ms, 2 V for 20min) was applied to bilateral Hoku (LI-4) and Zusanli (ST-36) on 12 hrs and 36 hrs after induction of colitis. EA-treatment significantly reduced the macroscopic damage and the myeloperoxidase activity of colonic samples at 3 days post-induction of colitis. Colitic colon showed a decreased in vitro motility. However, colonic motility of EAtreated group was not significantly different from that of normal group. The anti-inflammatory effect of EA was not inhibited by a glucocorticoid receptor antagonist, RU-486, but suppressed by a beta-adrenoceptor antagonist, propranonol. These results suggest that EA-treatment has a beneficial effect on colitis, and its anti-inflammatory effect is mediated by beta-adrenoceptor activation but not by endogenous glucocorticoiddependent mechanism.

General pharmacological profiles of bee venom and its water soluble fractions in rodent models

Recently, the antinociceptive and anti-inflammatory efficacy of bee venom (BV, Apis mellifera) has been confirmed in rodent models of inflammation and arthritis. Interestingly, the antinociceptive and anti-inflammatory effect of whole BV can be reproduced by two water-soluble fractions of BV (>20 kDa:BVAF1 and<10 kDa: BVAF3). Based on these scientific findings, BV and its effective water-soluble fractions have been proposed as potential anti-inflammatory and antinociceptive pharmaceuticals. While BV's anti-inflammatory and antinociceptive properties have been well documented, there have been no careful studies of potential, side effects of BV and its fractions when administered in the therapeutic range (BV, 5 microgram/kg; BVAF1, 0.2 microgram/kg: BVAF3, 3 microgram/kg; subcutaneous or intradermal). Such information is critical for future clinical use of BV in humans. Because of this paucity of information, the present study was designed to determine the general pharmacological/physiological effects of BV and its fractions administration on the rodent central nervous, cardiovascular, respiratory and gastrointestinal system. Subcutaneous BV and its fractions treatment did not produce any significant effects on general physiological functions at the highest dose tested (200-fold and 100-fold doses higher than that used clinically, respectively) except writhing test. These results demonstrate that doses of BV or BV subfractions in the therapeutic range or higher can be used as safe antinociceptive and anti-inflammatory agents.

Role of mucosal mast cells in visceral hypersensitivity in a rat model of irritable bowel syndrome

The involvement of mucosal mast cells (MMC) in the pathophysiology of irritable bowel syndrome (IBS) is still controversial. We aimed to re-evaluate the role of MMC in visceral hypersensitivity associated with IBS using a rat IBS model that develops the IBS symptom after a subsidence of acetic acid-induced colitis. No significant difference in the number of MMC was observed between normal rat colon and IBS rat colon. (61.7 +/-2.9/mm 2 in normal vs. 88.7 +/-13.3/mm 2 in IBS, p >0.29). However, the degranulation rate of MMC was significantly higher in IBS rat colon (49.5 +/-2.4% in normal vs. 68.8 +/-3.4% in IBS, p >0.05). Pretreatment of a mast cell stabilizer, doxantrazole (5 mg/kg, i.p.), reduced the degranulation rate of MMC and significantly attenuated visceral hypersensitivity to rectal distension in IBS rat, whereas it had no effect on the visceral sensory responses in normal rat. These results suggest that, although the number of MMC is not significantly changed in IBS rat colon, the higher degranulation rate of MMC is responsible for visceral hypersensitivity in this model IBS.

Effect of Acupuncture in the Treatment of Young Pigs with Induced Escherichia coli Diarrhea

The effect of acupuncture in the treatment of young pigs with induced enteropathogenic Escherichia coli diarrhea was histopathologically evaluated by routine hematoxylin and eosin stain. Thirty two pigs weighed 4-5kg and aged 21days old were used in this study. The animals with diarrhea were treated with traditional acupuncture, or enrofloxacin. In the group treated with traditional acupuncture, acupoint GV1 (Jiaochao) was used and in the group treated with antibiotics, enrofloxacin was injected intramuscularly. Ten pigs were inoculated with E. coli, but were not treated and served as nontreated control group. At postinoculation day 6, all pigs of the acupuncture and antibiotic treated groups recovered from diarrhea. In the ascending and descending colons of the nontreated control group, severe infiltration of inflammatory cells in the lamina propria was observed and in the fundic stomach, destruction of the fundic gland architecture and necrotic lesions were observed, however, in the same sites of the acupuncture and antibiotics treated groups, the mucosae of the colon and stomach were relatively similar to those of the normal group. These results indicate that acupuncture treatment is effective in controlling induced E. coli diarrhea in pigs at its early stage.

The Antinociceptive and Anti-inflammatory Effect of Ethylacetate Extracts from Bang-Poong (Radix ledebouriellae) on the Freund's Adjuvant-Induced Arthritis in Rats

In this study, we aimed to determine the antinociceptive and/or anti-inflammatory effect of Bang-Poong (BP, Radix Ledebouriellae) on Freund's adjuvant-induced arthritis in rats. Traditionally, BP has been used to treat several inflammatory diseases such as arthritis. Whole BP is extracted into two fractions that were ethylacetate and hexane-soluble fractions. Adult Sprague-Dawley rats (n=30, 130-150 g) were subcutaneously administered by the Freund's complete adjuvant (FCA) into the plantar surface of right hindpaw. Twelve days after the injection of FCA, the rats initially showed typical inflammatory edema and arthritis-related symptoms on the contralateral side (i.e. left hindpaw). Both antinociceptive (evaluation of mechanical, thermal pain threshold and analysis of spinal Fos expression) and anti- inflammatory (evaluation of paw edema, serum interleukin-6 level and x-ray analysis) effect of BP extracts were examined. The ethylacetate fraction of BP (BPE) significantly suppressed the FCA-induced paw edema as well as the serum level of interleukin-6 and it alleviated the radiological changes. Moreover, both mechanical and thermal hyperalgesia were attenuated by the treatment of BPE. In addition, spinal Fos expression that was increased by FCA- injection was suppressed in BPE group. Therefore, this study showed that BPE produced significant both antinociceptive and anti-inflammatory effects on FCA- induced arthritis in rats, while hexane fraction of BP did not show these effects. In conclusion, it is suggested that the ethylacetate fraction of BP is recommended to alleviate the arthritis-related symptoms in human according to the results of this study.