4
Views
9
CrossRef citations to date
0
Altmetric
Original Article

The Half-Life of Luteinizing Hormone in Intact and Castrated Quail During Fhotoferiodic Stimdlation

, , &
Pages 243-256 | Published online: 07 Jul 2009
 

Abstract

In the Japanese quail (Coturnix coturnix japonica) the plasma concentration of luteinizing hormone (LH) depends on the physiological state of the animal. Low levels are found in sexually immature birds on short days (0.8 ± 0.1 (n=20) ng/ml) while after exposure to long days, sexually mature birds have a significantly higher LH level (4.4 ± 0.4 (n=20) ng/ml). Castration of long day males results in an even higher rise in LH concentration to 16.8 ± 1.8 (n=16) ng/ml. When the half-life (t1/2) of circulating LH was determined it was found to have two components: a fast t1/2 of about 6 min and a Blower component of either 20 min (determined by a radioisotope method), or 40 min (following hypophysectomy). No significant difference was observed in either of these components between birds in the three physiological states (short days, long days, castration plus long days). It would appear, therefore, that since the half-life of plasma LH remains constant, the difference in circulating LH observed under the various physiological conditions results solely from a change in the rate of LH secretion.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.