Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Effects of Intravenous and Intraventricular Injection of Antisera Directed against Corticotropin-Releasing Factor on the Secretion of Anterior Pituitary Hormones

N. Ono, W. K. Samson, J. K. McDonald, M. D. Lumpkin, J. C. Bedran De Castro and S. M. McCann
Proceedings of the National Academy of Sciences of the United States of America
Vol. 82, No. 22 (Nov. 15, 1985), pp. 7787-7790
Stable URL: http://www.jstor.org/stable/26461
Page Count: 4
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Effects of Intravenous and Intraventricular Injection of Antisera Directed against Corticotropin-Releasing Factor on the Secretion of Anterior Pituitary Hormones
Preview not available

Abstract

To determine the physiological significance of corticotropin-releasing factor (CRF) in the control of pituitary hormone secretion, highly specific antibodies directed against the peptide were injected either intravenously or intraventricularly (third ventricle) and the effect on plasma levels of pituitary hormones was determined before and after application of ether stress for 1 min. The intravenous injection of CRF antiserum (0.5 ml) did not significantly alter basal corticotropin (ACTH) levels in freely moving ovariectomized rats but largely blocked the increase in plasma ACTH resulting from ether stress. These antibodies had no effect on the etherinduced decline in plasma growth hormone (GH), and they failed to modify plasma luteinizing hormone levels. In a second experiment, CRF antiserum (3 μ l) or normal rabbit serum was injected into the third ventricle. A blood sample was drawn 24 hr later and immediately thereafter another injection of CRF antiserum or normal rabbit serum was made. There was no modification in the level of any of the hormones 24 hr after the first injections, and they were similar in CRF antiserum and normal rabbit serum-injected animals. After imposition of ether stress, the response of plasma ACTH was nearly completely blocked by the intraventricular CRF antiserum, but the degree of blockade was slightly less than that obtained by intravenous injection. The decline in plasma GH after ether stress was blocked by the intraventricular CRF antiserum. There was no effect of the intraventricular injection of the antiserum on the levels of the other pituitary hormones. The results with intravenous injection of the antisera indicate that CRF plays an extremely important but probably not completely indispensable role in the release of ACTH after ether stress. The results of the intraventricular injection of the antiserum suggest strongly that endogenous CRF may also modify its own release in response to stress, augmenting it by a positive ultrashort loop feedback, and that the antisera against the peptide blocked this action; however, an action at the pituitary of these intraventricularly injected antibodies cannot be completely ruled out. The blockade of the stress-induced suppression of GH release by the CRF antibodies suggests that CRF released intrahypothalamically during ether stress brings about an alteration in the hypothalamic control of GH secretion such that the stress-induced inhibition of GH release is blocked.

Page Thumbnails

  • Thumbnail: Page 
7787
    7787
  • Thumbnail: Page 
7788
    7788
  • Thumbnail: Page 
7789
    7789
  • Thumbnail: Page 
7790
    7790