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Immunogold studies on the gonadotropes in adenohypophysis of the Korean native goat
1999
Lee, I.S. | Lee, H.S. | Song, S.H. | Yoon, S.T. | Hwang, I.K. (Seoul National University, Suwon (Korea Republic). College of Veterinary Medicine) | Seo, J.H. (Seoul National University, Seoul (Korea Republic). College of Medicine | Kang, T.C. | Won, M.H. (Hallym University, Chuncheon (Korea Republic). College of Medicine)
There have been a number of studies of gonadotropes secretin LH and FSH in the adenohypophysis, but the pattern of hormone storage and secretion of these cells still remains a controversial matter. In this study, we examined whether gonadotropes contained both of LH and FSH, and if so, how these hormones were distributed within the secretory granules. Hypophyseal sections of Korean native goat were simultaneously immunostained for LH and FSH antisera by protein A-gold technique. It was found that most gonadotropes contained both FSH and LH, but hormone storages in the secretory granules were some different among cells. Three types of gonadotropes were identified by the shape and size of the secretory granules and their hormone storage patterns. One type(I) of gonadotropes contained oval secretory granules, which immunoreactivity for FSH and LH were very weak. The size of secretory granules ranged from 160 to 310nm in diameter. Most granules contained both FSH and LH, but some contained only one of them. In another type(II)of gonadotropes, the immunreactivity and hormone storage patterns of the secretory granules were similar to those of type I cells. However, the secretory granules were round in shape and larger in size than those of type I. The other gonadotropes(type III) were distinctly distinguished by plenty of hormones in their secretory granules which were densely packed with numerous immunolabelled gold particles. These data are some inconsistent with other results that have been obtained in other ruminants like as cattle and sheep.
Показать больше [+] Меньше [-]Localizations of substance P, CGRP and calcium binding proteins in Korean native goat duodenum
1999
Lee, I.S. | Lee, H.S. | Song, S.H. | Yoon, S.T. | Hwang, I.K. (Seoul National University, Suwon (Korea Republic). College of Veterinary Medicine) | Kang, T.C. | Won, M.H. (Hallym University, Chuncheon (Korea Republic). College of Medicine) | Seo, J.H. (Seoul National University, Seoul (Korea Republic). College of Medicine)
The localization of substance P(SP), calcitonin gene-related peptide(CGRP) and three calcium binding proteins, calbindin D-28k(CB), calretinin(CR) and parvalbumin(PA) was immunohistochemically examined in the myenteric and submucous plexuses of Korean native goat duodenum. In the neurons of myenteric and submucous plexuses of duodenum, immunoreactivities of SP, CGRP and CB were confirmed in both nerve cell bodies and fibers. In contrast, CR immunoreactivity was found only in nerve fibers of myenteric plexuses, while PA immunoreactivity was found only in nerve cell bodies of submucoun plexuses. In the inner circular muscle layer, dense SP-like immunoreactive fibers were prominent but only a few CGRP-like immunoreactivities were observed. Most of SP-and CGRP-like immunoreactive neurons of both plexuses colocalized with CB. This result showed that SP and CGRP may have a important role for the movement of small intestine. The colocalizations of CB with SP or CGRP in myenteric and submucous plexuses suggest that CB may serve neuromodulatory role for SP-and CGRP-immunoreactecd neurons on the movement of intestinal wall.
Показать больше [+] Меньше [-]Regulation of thyroxine release in the thyroid by protein kinase C
1999
Kim, J.S. (Chonbuk National University, Chonju (Korea Republic). College of Veterinary Medicine)
Previous studies suggested that the inhibition of thyroxine (T4) release by alpha1-adrenoceptor and muscarinic receptor stimulation results in activated protein kinase C (PKC) from mouse and guinea pig thyroids. In the present study, the effect of carbachol, methoxamine, phorbol myristate acetate (PMA), and R59022 on the release of T4 from the mouse, rat, and guinea pig thyroids was compared to clarify the role of PKC in the regulation of the release of T4. The thyroids were incubated in the medium containing the test agents, samples of the medium were assayed for T4 by EIA kits. Forskolin, an adenylate cyclase activator, chlorophenylthio-cAMP sodium, a membrane permeable analoge of cAMP, and isobutyl-methylxanthine, a phospho-diesterase inhibitor, like TSH (thyroid stimulating hormone), enhaced the release of T4 from the mouse, rat, and guinea pig thyroids. Methoxamine, an alpha1-adrenoceptor agonist, inhibited the TSH-stimulated release of T4 in mouse, but not rat and guinea pig thyroids. In contrast, carbachol, a muscarinic receptor agonist, inhibited the release of T4 in guinea pig, but not mouse and rat thyroids. These inhibition were reversed by prazosin, an alpha1-adrenoceptor antagonist or atropine, a muscarinic antagonist or M1- and M3- muscarinic antagonists, in mouse or guinea pig thyroids. In addition, staurosporine, a PKC inhibitor, reversed methoxamine or carbachol inhibition of TSH stimulation. Furthermore, PMA, a PKC activator, and R59022, a diacylglycerol (DAG) kinase inhibitor, inhibited the TSH-stimulated release of T4 in mouse, rat, and guinea pig thyroids. These inhibition were blocked by staurosporine. these findings suggest that the activation of receptor or DAG inhibits TSH-stimulated T4 release through a PKC-dependent mechanism in thyroid gland.
Показать больше [+] Меньше [-]Species characterization of animal by muscle composition analysis I. The contents of histidine dipeptides in muscle from various species
1999
Lee, M.H. | Kim, S.K. (Chungnam National University, Taejon (Korea Republic). College of Veterinary Medicine) | Jung, G.S. | Park, J.M. (National Veterinary Research and Quarantine Service, Anyang (Korea Republic).)
The contents of histidine dipeptides, a metabolic products of muscle protein, were investigated to compare muscle composition among the 9 domestic animals including cattle. In major domestic animal, analyzed the effects of age, part and sex of the animals on their muscle composition. Large amounts of carnosine(68.63+_17.41 micro mol/g) were detected in cattle and it was higher than other animals. Wheres the content of anserine showed high level in order of turkey, chickens and duck. The ratio of carnosine and anserine(C/A ratio) was different depending on the animal species. Statistical data indicated that difference among species was significant(p0.05). The contents of histidine dipeptides in hearted muscle by boiling for 40 minutes at 110 degrees centigrade was similar to those of raw muscle. C/A ration in heated muscle was not different from that of raw muscle, indicating that no change has been made after heating process. The contents of camosine and anserine were different according to the parts of their muscle. Especially chuck of the mammalian showed extremely low level of histidine dipeptides compared with other parts, while C/A ratio maintained certain level regardless of age, part, sex. Therefore, based on the content of histidine depeptides, could be found the difference of muscle composition among the species. Also C/A ratio of horse, pig, cattle, duck, sheep nd turkey were characteristic respectively.
Показать больше [+] Меньше [-]Diagnosis of bovine tuberculosis by sing intradermal comparative tuberculin test and gamma-interferon assay
1999
Cho, Y.S. | Kim, J.M. | Jung, S.C. | Woo, S.R. | Kim,J.Y. | Ahn, J.S. (National Veterinary Research and Quarantine Service, Anyang (Korea Republic).) | Yoo, H.S. | Park, Y.H. (Seoul National University, Suwon (Korea Republic). College of Veterinary Medicine)
Since Robert Koch found tubercle bacilli in 1882, the studies on tubercle bacilli of human and animal had been carried out. Being old tuberculin(OT) introduced in 1890, the specificity of the diagnosis of tuberculosis has been improved by continual uses of heat concentrated synthetic medium(HCSM) and purified protein derivatives(PPD) tuberculin. Now, two types of tuberculin test are used worldwidly; the single intradermal test(SIT) using bovine tuberculin and the single intradermal comparative tuberculin test(SICTT) using avian and bovine tuberculins. In the SICTT, each countries have used with different combination of both avain and bovine tuberculins' titers. However, this kinds of studies have not reported in Korea. Therefore, the studies on the combination of their tuberculins' titers were performed through intradermal test of guinea pigs sensitized with either Mycobacterium bovis or M avium and were examined in 10 cattles of SIT positive reactors. Also, IFN-y assay, the latest diagnostic method of bovine tuberculosis, was experimentally applied to SIT positive reactors. For determinint the optimal titers, sensitized guinea pigs with M bovis and M avium were intradermally injected avain and bovine tuverculin. In guinea pigs sensitized with M bovis, bovine tuberculin 50 T.U. showed significant difference from all tested concentrations of avian tuberculin(p0.05). In guinea pigs sensitized with M avium, there is significantly different between bovine tuberculin and avian tuberculin by 25 T.U.(p0.01). Therefore, optimal titers of bovine and avian PPD tuberculins' titers for the SICTT in Korea were 5,000 and 2,500 tuberculin units, respectively, and the swelling differences between bobine and avian site in SIT positive reactors were above 3mm. Also, in IFN-y assay, the 9 SIT positive reactors were showed all the positive reactions.
Показать больше [+] Меньше [-]Effects of Ca2+ on protein kinase C activation in atrial natriuretic peptide regulation
1999
Kang, C.W. | Kim, J.S. | Lee, H.I. (Chonbuk National University, Chonju (Korea Republic). Bio-Safety Research Institute)
Atrial natriuretic peptide(ANP) is a hormone with potent natriuretic, diuretic and relaxing properties on vascular smooth muscle. Specific chemical modulator in response for the ANP secretion has not been found yet. Therefore, we have investigated the role of Ca2+ responsible for the regulation of ANP induced by protein kinase C(PKC) on mechanically stretch-induced ANP secretion in the rat atria. The results obtained were as follows; 1. ANP secretion and ANP concentration were increased to more in Ca2+-free buffer than in the Kreb-Henseleit buffer on mechanically stretch-induced ANP secretion(p0.05), but extracellular fluid translocation(ECF) was not significant. Phorbol 12-myristate 13-acetate(PMA, 10-7M) induced ANP secretion and ANP concentration in Ca2+-free buffer shown to more accentuate on mechanically stretch-induced ANP secretion than in the Ca2+-free buffer(p0.05), but ECF translocation was not significant. 2. In the presence of ryanodine(3*10-6M), PMA(10-7M) induced ANP secretion and ANP concentration in the Kreb-Henseleit buffer were shown to more increase on mechanically stretch-induced ANP secretion than in the ryanodine(3*10-6M) with the Kreb-Henseleit buffer(p0.05), but ECF translocation was not significant. 3. In the presence of ryanodine(3*10-6M), PMA(10-7M) induced ANP secretion and ANP concentration in the Ca2+-free buffer was shown to more increase on mechanically stretch-induced ANP secretion than in the ryanodine(3*10-6M) with the Ca2+-free buffer on mechanically induced ANP secretion(p0.05), but ECF translocation was not significant. The results suggest that PKC-induced ANP secretion may not be related to the change of Ca2+ on mechanically induced ANP secretion in the rat atria.
Показать больше [+] Меньше [-]Immunohistochemical study onthe expression of bcl-2 protein during follicular development and atresia in the rat ovary
1999
Koh, P.O. | Kwak, S.D. (Gyeongsang National University, Chinju (Korea Public). Institute of Animal Medicine, College of Veterinary Medicine) | Jeong, S.Y. | Cho, G.J. | Choi, W.S. (Gyeongsang National University, Chinju (Korea Public). Department of Anatomy, College of Medicine)
In the mannalian ovary, follicular development and stresia continuously occur during the reproductive cycles. Follicular atresia occurs through granulosa cell apoptosis. Apoptosis is known as the physiological cell death, which is regulated by bcl-2 gene family. In the vcl-2 gene family, bcl-2 and bcl-xLong are known as inhibitors of apoptosis, whereas bax and bcl-xShort are known as inducer of apoptosis. We thought that bcl-2 protein is associated with follicular development and atresia. But it is not known that the distribution of cells containing bcl-2 protein during follicular development and atresia. Therefore, to examine the distribution of cells with bcl-2 protein during ovarian follicular development and atresia. Therefore, to examine the distribution of cells with bcl-2 protein during ovarian follicular development and atresia, the immunohistochemistry was used ih the rat ovary. Bcl-2 immunorectivity was localized in the intestitial cells, theca externa cells and granulosa cells around of antrum. All positive sighals were observed in the cytoplasm of these cells. Positive sighals were strongly observed in the interstitial and theca externa cells of growing antral follicles. While, positive signals were weakly observed in these cells from atretic antral follicles. Positive sighals were very weakly observed in the granulosa cells of growing and atreticantral follicles. According to these data, we suggested that bcl-2 proteins which were wtrongly expressed in the interstitial cells and theca externa cells of growing antral folicles inhibit follicular atresia. And wer purposed that bcl-2 proteins regulated follicular development and atresia through the action of acl-2 gene family.
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