We investigated the changes in plasma sex steroid hormones, testosterone (T), estradiol-17β (E2), 17,20 β-dihydroxy-4-pregnen-3-one (17α20βOHP), 11-ketotestosterone (11KT) and cortisol levels from ribbed gunnel, Dictyosoma burgeri in associated with annual reproductive cycle. The fish were collected at the coastal waters of Dadaepo, Busan, Korea from August 2002 to March 2003. Body weight, liver weight and gonad weight were measured for calculation of hepatosomatic index (HSI) and gonadosomatic index (GSI). Plasma steroid and cortisol levels were measured by radioimmunoassay and data were analyzed using the Kruskal-Wallis test and the Spearman rank correlation. The GSI of females increased from November, peaked in February (13.21±2.27) and decreased rapidly from March (1.05±0.23). The GSI of males also increased from November, peaked in December (0.36±0.12) and remained high to February. In females, E2 levels increased and remained high from December to February (19.81±7.46～22.85±6.18 ng/ ㎖). The levels of T showed a similar tendency and correlated (rs=0.813, p=0.0001) significantly with E2 levels. The levels of 17α20βOHP increased rapidly in February (4.78±1.01 ng/㎖) and peaked in July (5.08±0.65 ng/㎖). Cortisol level was peaked in March (2081.07±1140.02 ng/㎖) and correlated significantly with 17α20βOHP levels (rs=0.790, p=0.0001). In males, the levels of T was peaked in January (2.43±0.17 ng/㎖) and then decreased rapidly. The levels of 11KT were remained high from October to January (3.27±1.55～4.28±1.53 ng/㎖) and correlated significantly with T levels (rs=0.513, p=0.002). On the other hand, the levels of 17α20βOHP fluctuated during reproductive cycle and the variation pattern of cortisol levels were similar to females. These results suggest that plasma sex steroids in ribbed gunnels have annual periodicity, and that cortisol may involve in maturation of females.

Cortisol은 난소내 다량으로 존재하며, 난소 세포에 그 수용체가 있는 것으로 보고되고 있다. 또한 사람의 과립 및 황체화 세포에서 cortisol은 스테로이드 생성과 세포 대사에 영향을 미치는 것으로 알려지고 있으나, 배란 후 난포액에 높은 농도로 존재하는 cortisol이 과립-황체화 세포에 어떤 영향을 미치는 지는 정확히 밝혀져 있지 않다. 따라서 본 실험에서 과배란 유도후 획득한 사람 과립-황체화 세포를 배양하면서 5, 50, cortisol

We examined the effects of the vibration stress on cortisol secretion and hematological characteristics in soft-shelled turtle, Pelodiscus sinensis. For the stressed group vibration of from electric vibrator applied for 30 min with 2-h intervals during daytime () up to 28 days. Using the blood samples collected from ten turtles held once a week after vibration stress, we measured hematocrit, hemoglobin, red blood cells, cortisol, glucose, lactic acid, osmolality, , aspartate aminotransferase (AST), and alanine aminotransferase (ALT). The results have showed that P. sinensis received vibration stress exhibit the 'typical' stress-induced physiological responses (cortisol, glucose, lactic acid, osmolality, ions, hematocrit and hemoglobin) induced by vibration stress. Our data suggested that chronic vibration stress caused substantial stress in the animal, and in particular, the persisting elevated levels of AST and ALT would be highly correlated with the adverse effects of the stress. The high hematological characteristics during entire experimental period showed that the P. sinensis could not adapt to chronic stimuli provoked by vibration stress.

Surgical patients have to deal with multiple stresses during hospitalization such as pain and physical discomfort, fear of medical procedures, and unfamiliarity with hospital equipment and environment. Using a blood cortisol test, one of the well-known measurements of stress responses, this study performed a randomized clinical trial with surgical patients to evaluate if plants in hospital rooms have therapeutic influences. Fifty-two patients recovering from a surgery were randomly assigned to hospital rooms with or without plants. Patients in the plant treatment room viewed seven species of foliage and flowering plants during postoperative recovery periods. Level of blood cortisol were compared between plant room patients and control room patients before surgery and discharge for two months. Patients in hospital rooms with plants and flowers had a significantly lower level of cortisol (p<0.044) as compared to patients in the control rooms. Male patients in plant rooms also showed a significantly lower level of cortisol (p<0.04) as compared to those in control rooms. No significant differences, however, were noted in female patients between control and plant rooms. The results of this study suggested that experience of plant interactions may positively affect patients' stress responses, thus increase relaxation. Further research will support hospital administrator and medical doctor decisions to use plants as a healing modality.