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Cortisol Metabolites (cortisol + metabolite)
Kinds of Cortisol Metabolites Selected AbstractsThe sensitive hare: sublethal effects of predator stress on reproduction in snowshoe haresJOURNAL OF ANIMAL ECOLOGY, Issue 6 2009Michael J. Sheriff Summary 1.,Prey responses to high predation risk can be morphological or behavioural and ultimately come at the cost of survival, growth, body condition, or reproduction. These sub-lethal predator effects have been shown to be mediated by physiological stress. We tested the hypothesis that elevated glucocorticoid concentrations directly cause a decline in reproduction in individual free-ranging female snowshoe hares, Lepus americanus. We measured the cortisol concentration from each dam (using a faecal analysis enzyme immunoassay) and her reproductive output (litter size, offspring birth mass, offspring right hind foot (RHF) length) 30 h after birth. 2.,In a natural monitoring study, we monitored hares during the first and second litter from the population peak (2006) to the second year of the decline (2008). We found that faecal cortisol metabolite (FCM) concentration in dams decreased 52% from the first to the second litter. From the first to the second litter, litter size increased 122%, offspring body mass increased 130%, and offspring RHF length increased 112%. Dam FCM concentrations were inversely related to litter size (r2 = 0·19), to offspring birth mass (r2 = 0·32), and to offspring RHF length (r2 = 0·64). 3.,In an experimental manipulation, we assigned wild-caught, pregnant hares to a control and a stressed group and held them in pens. Hares in the stressed group were exposed to a dog 1,2 min every other day before parturition to simulate high predation risk. At parturition, unsuccessful-stressed dams (those that failed to give birth to live young) and stressed dams had 837% and 214%, respectively, higher FCM concentrations than control dams. Of those females that gave birth, litter size was similar between control and stressed dams. However, offspring from stressed dams were 37% lighter and 16% smaller than offspring from control dams. Increasing FCM concentration in dams caused the decline of offspring body mass (r2 = 0·57) and RHF (r2 = 0·52). 4.,This is the first study in a free-ranging population of mammals to show that elevated, predator-induced, glucocorticoid concentrations in individual dams caused a decline in their reproductive output measured both by number and quality of offspring. Thus, we provide evidence that any stressor, not just predation, which increases glucocorticoid concentrations will result in a decrease in reproductive output. [source] Noninvasive Stress and Reproductive Measures of Social and Ecological Pressures in Free-Ranging African ElephantsCONSERVATION BIOLOGY, Issue 4 2001C. A. H. Foley This, coupled with political pressures to delist the elephant, has created a need for noninvasive physiological measures that can quantify the long-term effects of past mortality patterns of this long-lived species. We collected fresh fecal samples from 16 female elephants in three different groups over 23 months at Tarangire National Park, Tanzania, and analyzed them for fecal progesterone and cortisol metabolites. Social and ecological measures were collected concurrently. Fecal progesterone metabolite measures corresponded significantly with stage of gestation, and appear to be able to confirm pregnancy in female elephants from as early as 3 months of gestation. We found that progesterone metabolite concentrations were significantly lower during the dry season than during the wet season after controlling for stage of gestation. Fecal cortisol metabolite concentrations showed the opposite seasonal pattern, being significantly higher in the dry season and inversely correlated with rainfall across seasons. Fecal cortisol metabolite concentrations also increased with group size and were correlated positively with dominance rank in the largest group. Our results suggest that measures of progesterone and cortisol metabolites in feces provide indices of reproductive function and physiological stress that can quantify both natural and human disturbances in African elephants. These measures are ideally suited for monitoring the long-term effects of social disruption from poaching and a variety of other management concerns. Resumen: Debido a la cacería furtiva, la población de elefante africano ( Loxodonta africana) declinó en un 60%, principalmente adultos, entre 1979 y 1988. Esto, aunado a presiones políticas para eliminar al elefante de las listas de especies en peligro, ha creado la necesidad de medidas fisiológicas no invasivas que puedan cuantificar efectos a largo plazo de patrones de mortalidad en el pasado de esta especie longeva. Recolectamos muestras fecales de 16 elefantes hembras en tres grupos diferentes en el Parque Nacional Tarangire, Tanzania a lo largo de 23 meses, y las analizamos para detectar metabolitos de progesterona fecal y de cortisol. Al mismo tiempo se recolectaron medidas sociales y ecológicas. Las medidas de metabolitos de progesterona fecal correspondieron significativamente con la etapa de gestación, y parecen permitir la confirmación de preñez en elefantes hembras tan temprano como a los tres meses de gestación. Las concentraciones de metabolitos de progesterona fueron significativamente menores durante la época de sequía que en la de lluvias después de controlar para la etapa de gestación. Las concentraciones de metabolitos de cortisol fecal mostraron un patrón estacional opuesto, siendo significativamente más altas en la época de sequía e inversamente correlacionados con la precipitación en todas las estaciones. Las concentraciones de metabolitos de cortisol fecal también incrementaron con el tamaño del grupo y se correlacionaron positivamente con el rango de dominancia en el grupo más grande. Nuestros resultados sugieren que las medidas de metabolitos de progesterona y cortisol en las heces proporcionan índices de la función reproductiva y del estrés fisiológico que puede cuantificar perturbaciones, tanto naturales como humanas, en elefantes africanos. Estas medidas son idealmente adecuadas para monitorear efectos a largo plazo de la disrupción social por la cacería furtiva y así como una variedad de aspectos del manejo. [source] 11b-hydroxysteroid dehydrogenase activity in proteinuric patients and the effect of angiotensin-II receptor blockadeEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2002M. N. Kerstens Abstract Background It has been suggested that an altered setpoint of the 11,HSD-mediated cortisol to cortisone interconversion towards cortisol contributes to sodium retention in nephrotic syndrome patients. We studied the parameters of 11,HSD activity in proteinuric patients, in particular its activity at the kidney level. We also studied the effect of angiotensin-II receptor blockade on the parameters of 11,HSD activity. Materials and methods Serum cortisol/cortisone ratio and the urinary ratios of (tetrahydrocortisol + allo-tetrahydrocortisol)/tetrahydrocortisone [(THF + allo-THF)/THE] and of urinary free cortisol/free cortisone (UFF/UFE) were measured in eight proteinuric patients and compared with eight matched, healthy subjects. Patients were subsequently studied after 4 weeks' treatment with losartan 50 mg day,1 and placebo, respectively. Results No significant differences between the proteinuric patients and the healthy subjects were observed in the serum cortisol, serum cortisone, serum cortisol to cortisone ratio, or in the urinary excretions of THF, allo-THF, THE, sum of cortisol metabolites, or the (THF + allo-THF)/THE ratio. Urinary free cortisol excretion and the UFF/UFE ratio were lower in the proteinuric patients than in the healthy subjects (56 ± 21 vs. 85 ± 24 pmol min,1, P < 0·05, and 0·39 ± 0·07 vs. 0·63 ± 0·28, P < 0·05, respectively). Mean arterial pressure and proteinuria were reduced significantly during losartan treatment, but without concomitant changes in peripheral cortisol metabolism. Conclusions Increased renal inactivation of cortisol in proteinuric patients does not support the contention that altered 11,HSD activity contributes to sodium retention in patients with nephrotic syndrome. Losartan 50 mg d.d. reduces mean arterial pressure and proteinuria, but does not exert a significant effect on the cortisol to cortisone interconversion. [source] Coat condition, housing condition and measurement of faecal cortisol metabolites , a non-invasive study about alopecia in captive rhesus macaques (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2006Hanspeter W. Steinmetz Abstract Background, Previous studies have characterized alopecia in captive rhesus macaques (Macaca mulatta) by a mixed partial to complete alopecia in a bilateral symmetric pattern. Methods, In this study, coat condition assessments were related to exogenous and endogenous factors in captive rhesus macaques under different housing conditions in order to identify disturbances in environmental factors controlling or influencing hair growth. Additionally, the degree of alopecia was investigated in relation to adrenal endocrine function as an indicator of social stress using faecal glucocorticoid measurements. Results, Hair loss was found to vary with season and sex, was most pronounced in adult females during the winter and spring months. Generally, infants were not affected, but alopecia developed during adolescence. However, the housing system, available enclosure space and variations in group size and composition also appeared to influence coat condition. Levels of immunoreactive cortisol metabolites (11-oxoetiocholanolone) in faeces were significantly negatively correlated with alopecia, suggesting a relationship between hypothalamic-pituitary-adrenal (HPA) axis activity and hair loss in captive rhesus macaques. Conclusions, Although the present study demonstrates the influence of the HPA axis on coat condition, it is not known if hair loss is caused by abnormal behaviour or hormonal imbalances of the HPA axis itself. Our data suggest that alopecia in rhesus macaques is a highly complex multicausal disorder. [source] Short-term growth and adrenal function in children with asthma treated with inhaled beclomethasone dipropionate hydroflouroalkane-134aPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 8 2006O. D. Wolthers Inhaled beclomethasone dipropionate (BDP) with the propellant hydrofluroroalkane-134a (HFA) has been designed to be equivalent in terms of safety to chlorofluorocarbon (CFC)-formulated metered dose inhalers (MDI). The aim was to assess whether BDP HFA MDI 100 ,g twice daily was equivalent to BDP CFC MDI 100 ,g twice daily in terms of effects on short-term lower leg growth rate (LLGR) and measures of hypothalamic,pituitary,adrenal (HPA) function. The study consisted of a randomized double-blind cross-over trial with three active, a run-in and two wash-out periods each consisting of 2 wk. The place of study was a secondary referral outpatient clinic. The subjects involved were 14 boys and 10 girls with asthma, aged 7,12 yr. They were all administered BDP HFA 100 ,g, BDP CFC 100 ,g and 200 ,g twice daily. The outcome measures included LLGR and 24-h urine-free cortisol (UFC) and total cortisol metabolites (TCM). Mean (SD) LLGR during run-in and BDP HFA 100 ,g, BDP CFC 100 ,g and 200 ,g twice daily periods were 0.43 (0.23), 0.09 (0.29), 0.10 (0.45) and 0.08 (0.27) mm/wk. The one-sided 97.5% confidence interval for the difference in LLGR between BDP HFA 100 ,g and BDP CFC 100 ,g was 0.24, thus, below the predefined criterion of 0.20 mm/week. Inter-period comparisons of active treatments showed no differences between means of LLGR, UFC or TCM. Though non-inferiority between BDP HFA and CFC 100 ,g twice daily in terms of effects on LLGR was not found, equivalence was suggested by comparisons of LLGR during run-in and active treatments and by HPA function measures. [source] Glucocorticoids contribute to the heritability of leptin in Scottish adult female twinsCLINICAL ENDOCRINOLOGY, Issue 1 2004A. M. Wallace Summary objective, The precise interactions between glucocorticoids and leptin are complex and poorly understood. The aim of the study was to investigate whether the glucocorticoid/leptin interaction is influenced by shared environmental or genetic factors. design, We investigated the heritability of body mass index (BMI), circulating leptin and urinary glucocorticoid metabolites [tetrahydrocortisol (THF), alloTHF and tetrahydrocortisone (THE)] in 54 monozygotic (MZ) and 39 dizygotic (DZ) female twins. Analysis was performed using a structural equation modelling package Mx, developed by Neale. results, Leptin and BMI showed substantial heritability (68·3% and 71·3%, respectively). Bivariate analysis indicated that the genetic determinants of BMI and leptin are partly shared. Total cortisol metabolites (THF + alloTHF + THE), the (THE + alloTHF)/THE ratio [a marker of 11,-hydroxysteroid dehydrogenase (11HSD) activity] and the alloTHF/THF ratio (marker for 5,-reductase activity) followed an environmental pattern. The heritability of leptin was significantly lowered to 63·8% (P = 0·012) when values were corrected for the influence of total cortisol metabolites but unaffected by markers of 11HSD and 5,-reductase activity. conclusions, We confirm that the genetic influence on both BMI and the circulating leptin concentration is substantial and show that these genetic determinants are highly correlated. These genetic factors, which are more likely to be dominant than additive, can be modestly but significantly modified by urinary total cortisol metabolites implying an adrenal influence. [source] | |||||||||||||