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ABSTRACT. Growth hormone (GH) is secreted in a pulsatile manner, but the underlying mechanisms of GH pulse generation remain to be resolved. In the present study, we investigated the relationship between GH pulses in the peripheral circulation and GH-releasing hormone (GHRH) and somatostatin (SRIF) profiles in the cerebrospinal fluid (CSF) of male goats. The effects of an intracerebrovent ricular (icv) injection of neuropeptide Y (NPY), galanin and ghrelin were also analyzed. Blood and CSF samples were collected every 15 min for 8 hr from the jugular vein and third ventricle, respectively. GH pulsatility in the goat was found to consist of distinct large pulses of 5 hr periodicity and small pulses of 1 hr periodicity. GHRH and SRIF in the CSF fluctuated in a pulsatile manner with 1 hr periodicity, and most of the descending phase of SRIF pulses were associated with the initiation of GH pulses. Icv injections of NPY, galanin and ghrelin stimulated GHRH release without affecting SRIF release. In addition, NPY suppressed, and galanin and ghrelin induced large GH pulses, although ghrelin was much more effective than galanin. These results suggest that an hourly fall in SRIF is involved in generating intrinsic circhoral rhythm of GH pulsatility. The mechanisms underlying the generation of large GH pulses of 5 hr periodicity remain unknown, while direct action of NPY and/or ghrelin on the pituitary might be involved. KEY WORDS: ghrelin, growth hormone, growth hormone-releasing hormone, NPY, somatostatin.J. Vet. Med. Sci. 66(9): 1071-1078, 2004 Growth hormone (GH) is secreted in a pulsatile manner in all mammalian species studied to date, and this pulsatility plays an important role in the regulation of somatic growth and metabolism [7,10,15,20]. Knowledge of the exact mechanisms underlying the generation of GH pulses is, therefore, of physiological and pathophysiological importance. It is generally accepted that GH pulses are governed by two hypothalamic peptides, GH-releasing hormone (GHRH) and somatostatin (SRIF), which are stimulatory and inhibitory for GH secretion, respectively [15,29,34,41]. Most studies on the neuroendocrine regulation of GH pulsatility have been performed in male rats, in which GH secretion is characterized by a strikingly regular ultradian rhythm with large secretory bursts of every 3-4 hr [15,41]. In the rat, indirect studies such as passive immunizations against GHRH and SRIF suggested that GH pulses depend on GHRH discharge in combination with a decrease in SRIF secretion [29,41]. However, the secretory profiles of GHRH and SRIF under physiological conditions in this species remain to be elucidated because of the technical difficulties involved in collecting pituitary portal blood from unanesthetized animals. On the other hand, direct measurement of GHRH and SRIF in the portal blood from conscious animals has been reported in the sheep [4,12,44]. According to these studies, GH pulsatility in the sheep seemed less regular and the secretory patterns of GHRH and SRIF seemed more complex than ...

Background Ophiopogon japonicas (L.f) Ker-Gawl has been used as a traditional Chinese medicine to cure acute and chronic inflammation and cardiovascular diseases including thrombotic diseases for thousands of years. Previous phytochemical studies showed that O. japonicus contained compounds with anti-inflammatory activity. The aim of this study was to identify and isolate compounds with anti-inflammatory activity from the rhizome of O. japonicas.MethodsCompounds were isolated by various column chromatography and their structures were identified in terms of nuclear magnetic resonance spectrum (NMR) and mass spectrum (MS). To measure the anti-inflammatory effects of thirteen compounds in LPS-induced RAW 264.7 macrophage cells, we used the following methods: cell viability assay, nitric oxide assay, enzyme-linked immunosorbent assay, quantitative real-time PCR analysis and western blotting analysis.ResultsOne new and twelve known compounds (mainly homoisoflavonoids) were extracted from O. japonicas, in which 4′-O-Demethylophiopogonanone E (10) was considered as a new compound, additionally, compounds 4-O-(2-Hydroxy-1- hydroxymethylethyl)-dihydroconiferyl alcohol (2) and 5,7-dihydroxy-6-methyl-3-(2′, 4′-dihydroxybenzyl) chroman-4-one (12) were isolated from the rhizome of O. japonicas for the first time. The isolated compounds Oleic acid (3), Palmitic acid (4), desmethylisoophiopogonone B [5,7-dihydroxy-3-(4′-hydroxybenzyl)-8- methyl- chromone] (5), 5,7-dihydroxy-6-methyl-3-(4′-hydroxybenzyl) chromone (7) and 10 significantly suppressed the production of NO in LPS-induced RAW 264.7 cells. Especially compound 10 showed the strongest effect against the production of the pro-inflammatory cytokine IL-1β and IL-6 with the IC50 value of 32.5 ± 3.5 μg/mL and 13.4 ± 2.3 μg/mL, respectively. Further analysis elucidated that the anti-inflammatory activity of compound 10 might be exerted through inhibiting the phosphorylation of ERK1/2 and JNK in MAPK signaling pathways to decrease NO and pro-inflammatory cytokines production.ConclusionsOur results indicated that 4′-O-Demethylophiopogonanone E can be considered as a potential source of therapeutic medicine for inflammatory diseases.

A new paraffin/surfactant/water emulsion (PSW) for volatile organic compounds (VOCs) controlling was prepared and its potential for VOCs removal was investigated. Results indicated that PSW-5 (5%, v/v) provided higher toluene absorption efficiency (90.77%) than the other absorbents used. The saturation pressure, Henry’s constant, and activity coefficient of toluene in PSW-5 were significantly lower than those in water, and toluene solubility (1.331 g·L−1) in the PSW-5 was more than 2.5 times higher than the value in water. Several factors potentially affecting the toluene absorption efficiency were systematically investigated. The results suggested that concentration and pH of PSW, absorption temperature, and gas flow rate all had a strong influence on the toluene absorption, but the inlet concentration of toluene had little effect on the toluene absorption. There were different absorbing performances of PSW-5 on different VOCs, and the ketones, esters, and aromatics were more easily removed by the PSW-5 than the alkanes. Regeneration and reuse of the PSW were possible; after 3 runs of regeneration the absorption efficiency of PSW-5 for toluene also could reach 82.42%. So, the PSW is an economic, efficient, and safe absorbent and has a great prospect in organic waste gas treatment.