Digitized by Kansas Correctional Industries

Finally, the isolation and cloning of black sea bream SL receptor using PCR cloning and protein pull down assay were also attempted. Based on the PCR cloning results, the phylogenetic analysis of nonsalmonids fish GHR1 and SLR protein sequence, the GHR1 data of tissue distribution and effects of environmental salinity and fasting in tilapia, along with the results of far western blot, black sea bream GHR1 is probably a receptor for SL, however there is also a SL specific receptor in black sea bream. / In hormone treated primary cell culture of nonspawning black sea bream pituitary, 10-8 M E2 significantly increases SL mRNA level but 10-10 M, 10-9 M, 10-8 M of E2 inhibit GH mRNA level in female black seabream; 10-8 M E2 also inhibits SL and GH mRNA expression in bisexual black sea bream; 10-8 M MT inhibits SL mRNA expression in male black sea bream but any concentration of MT detected shows no significant effect on GH mRNA level. / Key words. somatolactin (SL), monthly changes, SL promoter, pit-1 and SL receptor / Somatolactin, SL, is a novel member of GH family of pituitary hormone only found in fish. It is considered to be a member of the GH gene family after gene duplication. Two types of SL, SL alpha and SL beta were identified, and SL 13 seems only in fresh water fish, such as goldfish, catfish, rainbow trout, eel and zebrafish. Black sea bream is a marine fish, and there is only SL alpha found from sequencing of over 100 SL cDNA clones. / The cDNAs encoding for transcription factor pit-1 variants were cloned and the transactivation of these Pit-1 isoforms on SL gene promoter were studied. Three variants of Pit-1 are first identified in fish. Pit-1b and Pit-1c can enhance SL promoter activity in Hepa-T1 cells respectively to about 2 fold and 12 fold, but pit-1a failed to activate the SL gene it in the same cells. All the three pit-1s of black sea bream couldn't reverse the inhibition of SL promoter in GH3 cells. The data suggest that N terminal 60 amino acid residues are critical in transactiation on SL promoter and SL promoter activity is possibly limited to fish SL secreting cells. / The SL gene promoter was obtained for gene regulation studies aiming to search for possible regulatory elements controlling the transcription of SL gene in black seabream. SL gene promoter is active in HepaT1 cells, but is inhibited in GH3 cells. Seven putative pit-1 response elements were confirmed with EMSA and super shift assay. / To study the physiological function of SL in black seabream, we initiated a study of monthly expressions of SL mRNA and gonadal somatic index (GSI) to determine whether SL is related to reproduction in black seabream, with GH mRNA levels were also detected for comparison. The results imply that function of SL is possibly related to early development of testis, while GH probably plays some roles in testis and ovary maturation. / by Tian, Jing. / "October 2007." / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4574. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 156-170). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Wang Yajun. / "April 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 212-248). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

No description available.

No description available.

No description available.

This investigation examined the influence of two levels of dietary sodium (Na+) intake on intramuscular and extracellular potassium (K+) content. Nine unacclimatized college males exercised. (90 minutes of treadmill walking, 5.6km/hr, 6X grade) in an environmental chamber maintained at 40.1( + .05)°C and 23.5( + . 4) %RH, during two 8-day dietary-acclimation regimens. The first regimen employed a high Na+ diet (399mEq/day), the second a low Na+ diet (98mEq/day); both diets contained 80mEq K+/day. Total body K+ stores increased during the high Na+ diet (+138mEq, 4.1%) and the-low Na+ diet (+114mEq, 3.4%). By day 8 (D8) of both treatments, subjects exhibited a significantly lower (p<.O5) mean heart rate and rectal temperature. Oxygen consumption and sweat rate were unaltered but sweat responsiveness (ml/hr/°c) progressively increased during the acclimation trials. Plasma volume increased +16.3% (D4) and +10.7% (D8) under the high Na+ diet and only +3.0% (D4) and +7.0% (D8) under the low Na+ diet. The low sodium diet was associated with a significantly higher (p<.05) mean heart rate (D3-D5), higher rectal temperature (D3-D6), lower sweat responsiveness (D2) and a delayed plasma volume expansion (D4)--resulting in less effective heat removal. The total content of K+, Na+, and C1- in plasma changed isoosmotically with plasma volume. The diets were associated with equivalent urine K+ excretion, and. during exercise in the heat both diets resulted in significantly decreased urine K+ losses. Muscle K+ and sweat K+ concentrations were not altered by dietary intervention or acclimation trials. Total muscle water-was significantly increased, in accord with Na+ and Cl- increases, on D8 of the low Na+ diet only. It was concluded that dietary intake of Na+, in combination with 8 days. of exercise in the heat and heavy sweating, does not significantly diminish the intramuscular K+ or total body K+ content.

Graduation date: 1982

Access to abstract permanently restricted to Ball State community only. / Access to dissertation permanently restricted to Ball State community only. / School of Physical Education, Sport, and Exercise Science

Not available / text