کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9113112 | 1156209 | 2005 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Prolactin in the brushtail possum (Trichosurus vulpecula): Development of homologous radioimmunoassay using recombinant possum prolactin
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موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
علوم غدد
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Prolactin in the brushtail possum (Trichosurus vulpecula): Development of homologous radioimmunoassay using recombinant possum prolactin Prolactin in the brushtail possum (Trichosurus vulpecula): Development of homologous radioimmunoassay using recombinant possum prolactin](/preview/png/9113112.png)
چکیده انگلیسی
We report the production of recombinant possum prolactin (posPrl), and its use in the development and validation of a highly specific homologous radioimmunoassay for the measurement of prolactin (Prl) in brushtail possums. This enabled the subsequent investigation of some basic mechanisms involved in the regulation of Prl secretion in this species. Recombinant posPrl spanning the entire coding region was expressed in Escherichia coli, resulting in a 199 amino acid protein with a molecular weight â¼23 kDa. The potency of posPrl was 45.3 ± 4.8% that of ovine Prl in a radioreceptor assay using possum mammary gland receptors and induced a 3.4 ± 0.8-fold increase in progesterone secretion in primary possum granulosa cells. Antiserum (G27) was raised against recombinant posPrl and was highly specific for possum Prl (â¼30% binding at 1:60,000 final dilution), and exhibited negligible cross-reactivity (<0.0001%) with possum growth hormone. Serial dilutions of pituitary gland extracts, and plasma samples from male and female possums gave parallel inhibition curves to recombinant posPrl standards in the assay. Biological validation of the RIA included treating possums with drugs known to alter Prl secretion in other mammals. In seasonally anoestrous female possums, administration of 20 μg thyrotropin-releasing hormone (TRH) resulted in a 15-fold increase (P < 0.01) in plasma Prl concentrations. In mid-late lactating female possums, a bolus of cabergoline (dopamine agonist; 75 μg) reduced (P < 0.05) plasma Prl levels to baseline for 24 h, while repeated administration (6 Ã 75 μg at 12 h intervals) suppressed (P < 0.01) plasma Prl concentrations until 24 h after the last injection. Prolonged inhibition of Prl levels subsequently caused marked (P < 0.01) attenuation in rate of bodyweight increase of pouch young. The amplitude of the Prl surge in response to a bolus of TRH (15 μg) was 5-fold lower in cabergoline-treated, compared to control mid-late lactating possums. In conclusion, we report the development and validation of a robust and sensitive RIA for measuring Prl concentrations in the plasma of brushtail possums.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: General and Comparative Endocrinology - Volume 142, Issue 3, July 2005, Pages 297-307
Journal: General and Comparative Endocrinology - Volume 142, Issue 3, July 2005, Pages 297-307
نویسندگان
J.L. Crawford, S. Lun, J. Demmer, D.C. Eckery,