Hymer WC, Cenci R, Grindeland R, Krishnan K, Nagaoka S, Snyder R, Salada T.

ASGSB Bull. 1995 Oct; 9: 89.

Biochemistry and Molecular Biology, Penn State Univ., University Park, USA.

Rationale. Rats and rat pituitary cells in microgravity show significant and repeatable changes in growth hormone (GH) and prolactin (PRL) cells (our laboratories-5 spaceflights). Objectives: This exp. was designed to demonstrate (a) the value of coupled technologies while at the same time trying to elucidate (b) mechanisms by which these changes might occur. Coupled Methods in microgravity: Cell culture; media harvest (4X) and storage; preparation of trypsin medium; cell removal by trypsinization; cell lysis; free flow electrophoresis (FFE) of cell lysate; down-link of OD 280 during FFE and fraction collection. Results. #1. Flight (F) cells released more immunoreactive GH (iGH) than synchronous ground (G) cells. #2. Bioactive GH (bGH) release was positively correlated with frequency of changes; F release of bGH was approximately 50% of controls with most severe reduction occurring early in flight. #3. HPLC analyses indicated relatively minor differences in released FiGH molecules (size, charge, pI). #4. Trypsinized cells reattached in microgravity. #5. FGH cells had significantly (p<0.02) less cytoplasmic area occupied by hormone. #6. Fibroblast growth in both F and G cultures was positively correlated with frequency of media change. #7. FFE of cell lysate in microgravity showed iGH over 14 fractions; a synchronous control lysate run at KSC showed iGH over 5 fractions. Analysis of F-FFE fractions by Western blot and HPLC sizing indicated some separation of iGH in microgravity. #8. F cells postflight released iGH and had different electrophoretic mobilities depending upon frequency of media change. #9. Release of iPRL from F cells was >G (4 changes) but Publication Types:

• Meeting Abstracts

Keywords:

• Animals
• Biotechnology
• Cell Culture Techniques
• Electrophoresis
• Growth Hormone
• Muridae
• Pituitary Gland
• Prolactin
• Rats
• Rats, Inbred Strains
• Rats, Sprague-Dawley
• Space Flight
• Weightlessness
• methods

Other ID:

• 97615501

UI: 102222731

From Meeting Abstracts