|Klemcke, Harold - FORMER ARS EMPLOYEE|
Submitted to: Federation of American Societies for Experimental Biology Conference
Publication Type: Abstract Only
Publication Acceptance Date: March 20, 2001
Publication Date: June 20, 2001
Citation: Klemcke, H.G., Vallet, J.L., Christenson, R.K. 2001. Cortisol influences on porcine embryonic development [abstract]. Proceedings of Federation of American Societies for Experimental Biology Conference (The FASEB Journal). 15:A70. Technical Abstract: An experiment was conducted to determine if maternal cortisol influenced early embryonic development. Pregnant pigs were randomly assigned to one of three treatments [vehicle controls (n = 7); metyrapone, a cortisol synthesis inhibitor (8 mg/kg; Met; n = 6); metyrapone + cortisol (100 ug/kg; Met+Cort; n = 6)] and surgically catheterized (jugular catheter for blood withdrawal, subcutaneous catheter for drug administration) on days 8 9 (term = 114 days). Treatments began on day 14 and were applied 3 times daily (0700, 1400, 2100 hr) through day 19. Blood samples were obtained at the same time intervals on days 14 and 18. On day 20, embryos were surgically removed. Maternal plasma cortisol concentrations were decreased 74% (p < 0.01) by Met and were restored to control levels by Met+Cort. There were no effects of treatment on embryonic survival or allantoic fluid concentrations of Na+, K+, or glucose. However, when data across all treatments were considered, significant second order polynomial regression were measured between maternal plasma cortisol concentrations and embryonic size (y = 87 + 898x -498x**2; p = 0.05), allantoic fluid volume (y = 12 + 84x 44x**2; p = 0.04), and allantoic membrane weight (y = -1.2 + 11x - 6x**2; p = 0.04). The existence of these relationships and their biphasic nature suggest an optimal range of cortisol concentrations for maximal conceptus size, and allantoic fluid volume.