title: Feeding frequency affects cultured rat pituitary cells in low gravity.
abstract: In this report, we describe the results of a rat pituitary cell culture experiment done on STS-65 in which the effect of cell feeding on the release of the six anterior pituitary hormones was studied. We found complex microgravity-related interactions between the frequency of cell feeding and the quantity and quality (i.e. biological activity) of some of the six hormones released in flight. Analyses of growth hormone (GH) released from cells into culture media on different mission days using gel filtration and ion exchange chromatography yielded qualitatively similar results between ground and flight samples. Lack of cell feeding resulted in extensive cell clumping in flight (but not ground) cultures. Vigorous fibroblast growth occurred in both ground and flight cultures fed 4 times. These results are interpreted within the context of autocrine and/or paracrine feedback interactions. Finally, the payload specialist successfully prepared a fresh trypsin solution in microgravity, detached the cells from their surface and reinserted them back into the culture chamber. These cells reattached and continued to release hormone in microgravity. In summary, this experiment shows that pituitary cells are microgravity sensitive and that coupled operations routinely associated with laboratory cell culture can also be accomplished in low gravity.
authors.affiliation: Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park 16802, USA.
authors.forename: W C
authors.initials: WC
authors.lastname: Hymer
authors.forename: R E
authors.initials: RE
authors.lastname: Grindeland
authors.forename: T
authors.initials: T
authors.lastname: Salada
authors.forename: R
authors.initials: R
authors.lastname: Cenci
authors.forename: K
authors.initials: K
authors.lastname: Krishnan
authors.forename: C
authors.initials: C
authors.lastname: Mukai
authors.forename: S
authors.initials: S
authors.lastname: Nagaoka
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000818:Animals; D001709:Biotechnology; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods; D048429:Cell Size; D003470:Culture Media; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D013006:Growth Hormone / Q000378:metabolism; D007986:Luteinizing Hormone / Q000378:metabolism; D008858:Microscopy, Phase-Contrast; D010903:Pituitary Gland, Anterior / Q000166:cytology* / Q000378:metabolism*; D010908:Pituitary Hormones, Anterior / Q000378:metabolism*; D011388:Prolactin / Q000378:metabolism; D051381:Rats; D013026:Space Flight / Q000295:instrumentation; D013972:Thyrotropin / Q000378:metabolism; D013997:Time Factors; D014893:Weightlessness / Q000009:adverse effects*
chemical_list: D003470:Culture Media; D010908:Pituitary Hormones, Anterior; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin; D013006:Growth Hormone