• Asian-Australasian Journal of Animal Sciences
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• v.11 no.1
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• pp.78-83
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• 1998

The objective of this study was to investigate the responsiveness of hypophysis and gonads to synthetic GnRH among prepubertal buffalo heifers at 12 months of age. Peripheral plasma FSH, LH, estradiol and progesterone level were measured in blood samples collected at 1 hr before and up to 18 days subsequent to the administration of $200{\mu}g$ GnRH (n=6) or saline (n=6) in Murrah buffalo heifers. The pretreatment peripheral plasma FSH, LH, estradiol and progesterone among GnRH treated heifers were $7.35{\pm}0.45ng/ml$, $1.08{\pm}0.3ng/ml$, $22.93{\pm}1.06pg/ml$ and $0.27{\pm}0.04ng/ml$ respectively. A quick elevation (p < 0.01) of FSH and LH within five min of GnRH administration was observed in all geifers. Although the peak FSH $(89.57{\pm}23.43ng/ml)$ and LH $(7.52{\pm}3.08ng/ml)$ reached by 10 min of GnRH administration, yet the animals differed both in terms of their amplitude response of FSH and LH release as well as in terms of time which animals took to exhiit maximum response to GnRH administration. The GnRH administration did not cause alteration in plasma estradiol and progesterone level. The present study suggests that the pituitary of 12 month buffalo heifers has capacity to synthesize and store of gonadotropin and have developed receptors for GnRH for a spike of gonadotropin release.

• Journal of Veterinary Clinics
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• v.20 no.2
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• pp.212-219
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• 2003

The effect of GnRH and/or hCG on the implantation, pregnancy, and the concentration of plasma estradiol and progesterone were studied in pregnant rats. GnRH 50, or 100ug and/or hCG 50 or 100 IU were administered once on day 2 or 9 of gestation, respectively. Rats were autopsied on days 8 or 16. Administration of GnRH on day 2 did not induce the prevention of implantation and termination of pregnancy but was able to induce termination of pregnancy administering on day 9. Administration of hCG induced delayed implantation on day 2 and termination of pregnancy on day 2 and 9. Administration of GnRH concomitant with hCG had no effect on prevention of implantation on day 2 but induced termination of pregnancy with a very increased fetal resorption on day 2 and with a moderate increased fetal resorption on day 9. Administration of GnRH concomitant with hCG on day 2 induced more increased termination of pregnancy compared to injection of GnRH or HCG and opposite result was observed on day 9. Plasma estradiol and progesterone concentrations by administering GnRH and/or hCG had no effect on the termination of pregnancy the pregnant rats.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.1-8
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• 2007

Atmospheric photochemistry of $O_3-NOx-RH$ were considered theoretically, to clarify the reasons for the different trends of between the formation of photochemical oxidants (Ox) and its primary pollutants for the Low-and High-NOx regimes. Equations of OH, $HO_2$, and production of ozone ($O_3$) as a function of nitrogen oxides (NOx) and reactive hydrocarbons (RH) were represented in this study. For the Low-NOx regime, $HO_2$ radical is proportional to RH but independent of NOx. OH radical is proportional to NOx but inversely-proportional to RH. $O_3$ production is proportional to NOx but has a weak dependence on RH. For the High-NOx regime, OH and $HO_2$ radicals concentrations and $O_3$ production are proportional to RH but inversely-proportional to NOx. In addition, the Osaka Bay and surrounding areas of Japan were evaluated with the mass balance of odd-hydrogen radicals (Odd-H) using CBM-IV photochemical mechanism, in order to distinguish the Low- and High-NOx regimes. The Harima area (emission ratio, RH/NOx = 6.1) was classified to the Low-NOx regime. The Hanshin area (RH/NOx = 3.5) and Osaka area (RH/NOx = 4.3) were classified to the High-NOx regime.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.84-84
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• 2010

We present an in-situ study of the interaction of a bimetallic Rh50Pd50 bulk crystal with O2, CO, and NO using ambient pressure x-ray photoelectron spectroscopy and compare it to results for 10 nm nanoparticles with the same overall composition. The surface of the bulk crystal has less Rh present under both oxidizing and reducing conditions than the nanoparticles under identical conditions. Segregation and oxidation/reduction proceeds quicker and at lower temperature for nanoparticles than for the bulk crystal. The near surface of the Rh50Pd50 bulk crystal after high temperature vacuum annealing is ca. 9% Rh measured by XPS. Heating in 0.1 Torr O2 to $350^{\circ}C$ increases the Rh surface composition to ca. 40%. The surface can then be reduced by heating in H2 at $150^{\circ}C$, leading to a reduced surface of 30% Rh. Titration of CO from this Rh-rich surface proceeds at a much lower pressure than on the Rh-deficient starting surface.

• Journal of Veterinary Clinics
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• v.3 no.1
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• pp.227-233
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• 1986

A total of 600 Holstein cows in Chonnam province was examined to make a diagnosis on the ovarian follicular cyst. By clinical signs and rectal examination, 57 cows were found to have ovarian follicular cyst. Attempts were made to treat the cows which had ovarian follicular cyst with GnRH, HCG respectively. The results obtained were summarized as follows : 1. The rates of estreous induction with GnRH or HCG were 91.4%, 77.2%, respectively. The GnRH treated group was showed significantly higher than HCG treated group. The mean days from the GnRH or HCG treated to estrum were 25.1 and 23.5 days, respectively. 2. The Conception rates with GnRH or HCG treatment were 78.2% and 76.5％, respectively. 3. Services per conception with GnRH or HCG treatment were 1.5 and 2.1 respectively. 4, Days from GnRH or HCG treatment to concept were 38.2 and 45.8 days, respectively. 5. Intramuscular injection with GnRH and intraovarian injection with HCG were revealed the most effective routes in all the other routes.

• Journal of Pharmaceutical Investigation
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• v.28 no.2
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• pp.99-107
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• 1998

The objective of this study was to develop effective oral formulations of rhEGF for gastric ulcer healing using polycarbophil. hydroxypropylcellulose(HPC) and sucralfate as its bioadhesive bases. Cytoprotective effects of rhEGF, cell proliferation and differentiation. on the ulcers induced by ethanol or acetic acid in rats were studied. rhEGF release from HPC formulation was much faster than that from polycarbophil formulation. HPC formulation combined with small amount of sucralfate showed much slower release of rhEGF than only HPC base only. rhEGF preparations with bioadhesive polymers showed better effects on the healing of gastric ulcers than EGF solution when administered orally. When rhEGF preparations were administered at once and the animals were under starvation, polycarbophil formulation showed better effect on gastric ulcers than HPC formulation. Otherwise, when rhEGF preparations were given more than three times and the rats were fed normally, HPC formulation showed good healing efficacy of ulcers compared to polycarbophil formulation. rhEGF showed dose-dependent effect on the healing of both chronic and acute ulcers.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.19-28
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• 1994

The effects of gonadoropin-releasing hormone (GnRH) and ovarian steroid hormones on the release of luteinizing hormone (LH) and its subunit mRNA levels were investigated in anterior pituitary cells in culture. LH concentration was measured by a specific radioimmunoassay and mRNA levels of u and $LH{\beta}$ subunits by RNA slot blot hybridization assay. GnRH stimulated LH release in a dose-dependent manner from cultured pituitary cells. However, the basal LH release in the absence of GnRH was not changed during the course of 24h culture, strongly suggesting that release of LH is directly controlled by GnRH. The treatment of the pituitary cells with GnRH increased $LH{\beta}$ subunit mRNA levels in a dose-dependent manner, reaching the maximum with $2\;{\times}\;10^{-10}M$ GnRH while no significant increase in ${\alpha}$ subunit mRNA levels was observed after GnRH treatment. Estradiol did not augment GnRH-induced LH release while progesterone augmented GnRH-induced LH release in a dose-dependent manner at the level of pituitary. However, estradiol and progesterone increased basal and GnRH-induced $LH{\beta}$ subunit mRNA levels in a dose-dependent manner. The treatment of estrogen antagonist, LYI17018 blocked the effect of estradiol on GnRH-induced $LH{\beta}$ subunit mRNA levels in a dose-dependent manner while progesterone antagonist, Ru486 tended to block the effect of progesterone on GnRH-induced $LH{\beta}$ subunit mRNA levels. It is therefore suggested that GnRH Playa a major role in LH release and subunit biosynthesis by influencing the steady state $LH{\beta}$ subunit mRNA loves and ovarian steroid hormones modulate subunit biosynthesis via directly acting on pituitary gonadotropes.

• The Korean Journal of Pharmacology
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• v.23 no.2
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• pp.57-75
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• 1987

Two modalities of gonadotropin secretion, pulsatile gonadotropin and preovulatory gonadotropin surge, have been identified in the mammals. Pulsatile gonadotropin secretion is modulated by the pulsatile pattern of GnRH release and complex ovarian steroid feedback actions. The neural mechansim that regulates the pulsatile release of GnRH in the hypothalamus is called "GnRH pulse generator". Ovarian steroids, estradiol and progesterone, appear to exert thier feedback effects both directly on the pituitary to modulate gonadotropin release and on a hypothalamic site to modulate GnRH release; estradiol primarily affects the amplitude while progesterone decreases the frequency of the pulsatile GnRH. Steroid hormones are known to affect catecholamine transmission in brain. MBH-POA is richly innervated by NE systems and close apposition of NE terminals and GnRH cell bodies occurs in the MBH as well as in the POA. NE normally facilitates pulsatile LH release by acting through ${\alpha}-receptor$ mechanism. However, precise nature of facilitative role of NE transmission in maintaining pulsatile LH has not been clearly understood. Close apposition of DA and GnRH terminals in ME might permit DA to influence GnRH release. Action of DA transmission probably is mediated by axo-axonic contacts between GnRH and DA fibers in the ME. Dopamine transmission does not normally regulate pulsatile LH release, but under certain conditions, increased DA transmission inhibit LH pulse. Endogenous opioid acts to suppress the secretion of GnRH into hypophysial portal circulation, thereby inhibiting gonadotropin secretion. However, an interaction between endogenenous opioid peptides and gonadotropin release is a complex one which involves ovarian hormones as well. LH secretion appears to be most suppressed by endogenenous opioids during the luteal phase, at a time of elevated progesterone secretion. The arcuate nucleus contains not only cell bodies for GnRH and ${\beta}-endorphin$ but also a dense aborization of fibers suggesting that GnRH release is changed by the interactions between GnRH and ${\beta}-endorphin$ cell bodies within the arcuate nucleus. The frequency and amplitude of pulsatile LH release seem to be increased during the preovulatory gonadotropin surge. Estradiol exerts positive feedback action on the hypothalamo-pituitary axis to trigger preovulatory LH surge. GnRH is also crucial hormonal stimulus for preovulatory LH surge. It is unlikely, however, that increased secretion of GnRH during the preovulatory gonadotropin surge represents an obligatory neural signal for generation of the LH discharge in primates including human. Modulation of preovulatory LH surge by catecholamines has been studied almost exclusively in rats. NE and E may be involved in distinct way to accumulate GnRH in the MBH and its release into the hypophysial portal system during the critical period for LH surge on proestrus in rats. However, the mechanisms whereby augmented adrenergic transmission may facilitate the formation and accumulation of GnRH in the ME-ARC nerve terminals before the LH surge have not been clearly understood.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.516-521
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• 1989

Reaction between the $N_2O_2-type$ tetradentate ligand, ethylenediamine-N,N'-di-S-${\alpha}$-isobutylacetic acid (SS-emiba) and $RhCl_3{\cdot}3H_2O$ has yielded ${\Delta}-s-cis-\;and\;{\wedge}-uns-cis-[Rh(SS-eniba)Cl_2]-$. ${\Delta}-s-cis-[Rh(SS-eniba)Cl_2]^-$ has been utilized to react with S-methyl-L-cystcine(Smc) to give ${\Delta}-s-cis-[Rh(SS-eniba(Smc)]^+$. The oxidation of ${\Delta}-s-cis-[Rh(SS-eniba(Smc)]^+$ using $H_2O_2$ has produced ${\Delta}-s-cis-[Rh(SS-eniba)(Smc-o)]^+$, in which the coordinated sulfur has been converted into the sulfoxide group. In a separate series of experiments the S-methyl-L-cysteine is oxidized by $H_2O_2$ to give S-methyl-L-cysteine sulfoxide, which is then coordinated to ${\Delta}-s-cis-[Rh(SS-eniba)Cl2]^-$ to make the standard complet of ${\Delta}-s-cis-[Rh(SS-eniba)(Sme-o)]+$ for comparison with the complex obtained from the oxidation of ${\Delta}-s-cis-[Rh(SS-eniba)(Smc)]^+\;by\;H_2O_2.$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.266-270
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• 1999

Two forms of gonadotropin releasing hormone (GnRH) are identified in the brain of adult mature spotted sea bass (Lateolabrax sp.) by immunohistochemical methods. Salmon GnRH immunoreactive (sGnRH-ir) cell bodies were distributed in the olfactory bulb, ventral telencephalon and preoptic region. Immunoreactive fibers were observed in the vicinity of the brain including the olfactory bulbs, the telencephalon, the optic nerve, the optic tectum, the cerebellum, the medulla oblongata and rostral spinal cord. In most cases, these fibers did not form well defined bundles. However, there was a clear continuum of immunoreactive fibers, extending from the olfactory bulbs to the pituitary. cGnRH-II-ir cell bodies were only found in olfactory bulbs. However, the distribution of cGnRH-II-ir fibers was basically similar to that of sGnRH-ir fibers except for the absence of their continuity between the olfactory bulbs and the pituitary. These data suggest that sGnRH and cGnRH-II are endogenous peptides and indicate the presence of multiple neuroendocrine functions in the brain of the spotted sea bass. It seems that sGnRH not only regulates GTH secretion but also functions as a neurotransmitter, whereas cGnRH-II functions only as a neurotransmitter.