NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Experiment K-7-22: Growth Hormone Regulation Synthesis and Secretion in MicrogravityImmunohistochemical analyses of hypothalamic hormones carried out on tissue from rats flown on an earlier flight (Cosmos 1887) suggested preferential effects on hypophysiotropic principles involved in the regulation of growth hormone secretion and synthesis. We found that staining in the median eminence for peptides that provide both stimulatory (growth hormone-releasing factor, or GRF) and inhibitory (somatostatin, SS) influences on growth hormone secretion were depressed in flight animals relative to synchronous controls, while staining for other neuroendocrine peptides, cortocotropin-releasing factor and arginine vasopressin, were similar in these two groups. While this suggests some selective impact of weightlessness on the two principal central nervous system regulators of growth hormone dynamics, the fact that both GRF- and SS-immunoreactivity (IR) appeared affected in the same direction is somewhat problematic, and makes tentative any intimation that effects on CNS control mechanisms may be etiologically significant contributors to the sequelae of reduced growth hormone secretion seen in prolonged space flight. To provide an additional, and more penetrating, analysis we attempted in hypothalamic material harvested from animals flown on Cosmos 2044 to complement immunohistochemical analyses of GRF and SS staining with quantitative, in situ assessments of messenger RNAs encoding the precursors for both these hormones.
Document ID
19960028999
Acquisition Source
Ames Research Center
Document Type
Other
Authors
Sawchenko, P. E.
(Salk Inst. La Jolla, CA United States)
Arias, C.
(Salk Inst. La Jolla, CA United States)
Krasnov, I.
(Institute of Biomedical Problems Moscow, USSR)
Grindeland, R. E.
(NASA Moffett Field, CA United States)
Vale, W.
(Salk Inst. La Jolla, CA United States)
Date Acquired
August 17, 2013
Publication Date
September 1, 1994
Publication Information
Publication: US Experiments Flown on the Soviet Biosatellite Cosmos 2044
Subject Category
Life Sciences (General)
Accession Number
96N29594
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Document Inquiry

Available Downloads

There are no available downloads for this record.
No Preview Available