Browsing by Subject "Prostaglandins"

Now showing 1 - 4 of 4
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    Differential expression of prostaglandin E receptor subtype EP2 in rat uterus during early pregnancy
    (Murcia : F. Hernández, 2005) Shi, J.J.; Ma, X.H.; Diao, H.L.; Ni, H.; Xu, L.B.; Zhu, H.; Yang, Z.M.
    PGE2 is essential for mammalian female reproduction. This study was to examine the expression of EP2 gene in the rat uterus during early pregnancy, delayed implantation and artificial decidualization by in situ hybridization and immunohistochemistry. There was no detectable EP2 mRNA expression in the uterus from days 1 to 4 of pregnancy (day 1 = day of vaginal sperm). A low level of EP2 immunostaining was observed in the luminal and glandular epithelium from days 1 to 4 of pregnancy. Both EP2 mRNA and protein expression were highly detected in the luminal epithelium at implantation sites on day 6 of pregnancy. EP2 expression decreased from day 7 of pregnancy and was undetectable on days 8 and 9 of pregnancy. After delayed implantation was terminated by estrogen treatment and the embryo implanted, both EP2 mRNA and protein expression were strongly observed in the luminal epithelium at the implantation site. There was no detectable EP2 expression in both control and decidualized uteri. In conclusion, these data suggest that EP2 expression at implantation site may play an important role during embryo implantation in rats.
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    Effects of indomethacin on sunburn and suntan reactions in hairless descendants of Mexican hairless dogs
    (Murcia : F. Hernández, 1998) Kimura, T.; Doi, K.
    The inhibitory effects of topical indomethacin (1M)-treatment on sunburn and suntan reactions after ultraviolet (UV)-irradiation were investigated in the dorsal skin of hairless descendants of Mexican hairless dogs. Skin color, plasma prostaglandin E2 (PGE2) and histological features were examined. At 1 day after UV-irradiation, the IM-untreated sites showed prominent erythema, while the IM-treated sites exhibited few visible erythematous reactions. From 4 days after UV-irradiation, both the IM-treated and -untreated sites began to develop skin pigmentation. Assessment of skin color changes, using a colorimeter, reflected precisely the color changes in visual sunburn and suntan reactions. Plasma PGE2 concentration began to increase from 2 hours after UV-irradiation, reached the maximal values at 24 hours and recovered at 96 hours after UVirradiation. Histologically, at 1 day after UV-irradiation, the IM-untreated sites showed remarkable epidermal degeneration (thickening and sunburn cells) and moderate alteration in the dermis. On the other hand, the IM-treated sites showed only minor histological changes. At 4 days after UV-irradiation, deposition of melanin granules was found in both the IM-treated and -untreated sites. At 7 days after UV-irradiation, pigmentation became more prominent in the stratum basale. These results revealed that UV-induced erythematous reactions of hairless dogs were closely related to the action of PGE2. Visually and histologically, topical IMtreatment had apparent inhibitory effects on erythematous reactions, while this agent showed no protective effects on epidermal pigmentation after UV-irradiation.
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    Hypertension and Sex Differences in the Age-Related Renal Changes When Cyclooxygenase-2 Activity Is Reduced During Nephrogenesis
    (American Heart Association, 2008-12-22) Saez, Fara; Reverte, Virginia; Salazar, Francisco; Llinás, María Teresa; Salazar, F. Javier; Castells Mora, María Teresa; Fisiología
    Several studies have proposed that cyclooxygenase-2 (COX2) is involved in the regulation of nephrogenesis and that an impaired nephrogenesis may induce the development of hypertension. This study was designed to test the hypothesis that the decrease of COX2 activity leads to a reduction in nephron number, an increase in arterial pressure, and age-dependent renal alterations that are greater in male than in female rats. Arterial pressure was measured from the first to the 16th month of life in rats treated with vehicle or a COX2 inhibitor during the nephrogenic period. Stereological and histological evaluations and renal function studies were performed at different ages. Arterial pressure increased (14%; P<0.05) and nephron number decreased (17%; P<0.05) to similar levels in male and female COX2-treated rats. However, glomerular filtration rate (31%) and renal plasma flow (25%) decreased (P<0.05) in male but not in female COX2-treated rats. A greater (P<0.05) age-dependent elevation in glomerular hypertrophy was also found in male COX2-treated rats compared with their female littermates. Glomerulosclerosis and tubulointerstitial damage in renal cortex and medulla were also significantly enhanced in male but not in female aged COX2-treated rats. Our results demonstrate that the decrease in COX2 activity during renal development leads to a reduction in nephron number and to an elevation in arterial pressure that are similar in males and females. However, the consequent age-dependent deterioration of the renal structure and renal function is only significantly enhanced in male rats.
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    Muscle injuries and repair: The role of prostaglandins and inflammation
    (Murcia : F. Hernández, 2003) Prisk, V.; Huard, J.
    Skeletal muscle injuries are a common problem in trauma and orthopaedic surgery. Muscle injuries undergo the healing phases of degeneration, inflammation, regeneration, and fibrosis. Current and experimental therapies to improve muscle regeneration and limit muscle fibrosis include conservative and surgical principles with the adjuvant use of non-steroidal anti-inflammatory drugs (NSAIDs) and growth factor manipulation. NSAIDs appear to have a paradoxical effect on the healing of muscle injuries with early signs of improvement and subsequent late impairment in functional capacity and histology. In vitro and in vivo studies have explored the role of the cyclooxygenases and prostaglandins in the biological processes of healing muscle, including precursor cell activation, myoblast proliferation, myoblast fusion, and muscle protein synthesis. Through use of more specific cyclooxygenase inhibitors, we may be able to better understand the role of inflammation in muscle healing.