Influence of in vitro glycosylation inhibitors on release of luteinizing hormone and characterization of luteinizing hormone isoforms from fetal calves /
Two experiments were conducted to investigate: 1) influence
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1997.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739887501&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Two experiments were conducted to investigate: 1) influence of glycosylation inhibitors, swainsonine (SW) and castanospermine (CA) on the release of LH from bovine pituitary cell cultures, and 2) characterization of LH isoform distribution in the pituitary of fetal calves. In Experiment 1. cultured pituitary cells from heifers (n=7; mean age = 630 + 56 d, mean BW = 354 + 58 kg) were utilized. Treatments were GNRH (10-7 M), SW (1,3 or 5 ug), CA (1, 25 or 100 ug), SW + GNRH or CA + GNRH. Mean LH concentration in medium containing CA1 (17.87 + .35ng/ml) did not differ from control (23.88 +.35 ng/ml). Mean LH concentration in media from CA25, 100 and the three doses of SW was higher (P<.05) than in control medium. Mean LH concentration in media from SW-treated cells decreased (P<-05) as treatment dose increased from SWI (46.2 +.91 ng/ml) to SW5 (33.25 +.63 ng/ml). Addition of GNRH to the medium increased (P<.05) LH concentration compared with the control (48.67+2.04 vs 23.88 + .34 ng/ml). In media from GNRH treated cells, mean LH concentration was elevated in response to the two higher doses of either SW or CA. We conclude that addition of inhibitors of glycosylation to cultured bovine pituitary cells does alter the quantity of immunoreactive LH release. In Experiment 2, Brahman crossbred heifers (n=12) were assigned randomly to one of two treatment groups: transportation on a stock trailer for 24.2 km, (TRANS, n = 6); or walked through the handling facilities (SHAM, n = 6). Treatments were repeated at 60, 80, 100, 120 and 140 d of gestation. Fetuses were delivered by Caesarian-section on d 266 of gestation. Blood samples were collected from the fetal calves to determine plasma ACTH and cortisol concentrations. TRANS fetuses were heavier than SHAM fetuses (28.7 vs 23.93 + 1.8 kg; P<.07). Differences were not detected between TRANS and SHAM treatments for ACTH and cortisol concentrations. Isoform profiles of fetal pituitaries revealed nine LH isoforms (A-I). Differences were not detected in LH isoform distribution due to gender, stress or their interaction. |
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| Item Description: | Vita. "Major Subject: Physiology of Reproduction". |
| Physical Description: | x, 112 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 66-77. |