AIMTo establish the rat model of morphine-induced conditioned place preference (CPP) and to investigate the effects of morphine psychical dependence on the levels of neurosteroids in rat brain.

METHODSRats were ip administered morphine 5 mg x kg(-1) for 10 days to induce CPP in morphine group. The concentrations of dehydroepiandrosterone (DHEA), pregnenolone (PREG), allopregnanolone (AP), dehydroepiandrosterone sulfate (DS) and pregnenolone sulfate (PS) in nucleus accumbens (Nac), hypothalamus (Ht), amygdale (A) and plasma of rats were determined with liquid chromatography-negative atmospheric pressure ionization mass spectrometry (LC-MS).

RESULTSTrained with morphine for 10 days resulted in the acquisition of CPP in morphine group with the time that the rats spent in drug-pairing room was longer than that of control group. Compared with control group, morphine treatment could significantly decrease the contents of DHEA in Nac and plasma, decrease that of PREG in Ht.

CONCLUSIONMorphine could induce the CPP in rats and affected the contents of some neurosteroids in rat brain, which suggests that endogenous neurosteroids might he related to the development of morphine dependence.

Amygdala ; metabolism ; Animals ; Brain ; metabolism ; Conditioning, Operant ; physiology ; Dehydroepiandrosterone ; blood ; metabolism ; Dehydroepiandrosterone Sulfate ; blood ; metabolism ; Hypothalamus ; metabolism ; Male ; Morphine Dependence ; metabolism ; Nucleus Accumbens ; metabolism ; Pregnanolone ; blood ; metabolism ; Pregnenolone ; blood ; metabolism ; Rats ; Rats, Sprague-Dawley

PURPOSE: The primary objective of this study was to examine the changes of basal cortisol and DHEA levels present in saliva and serum with age, and to determine the correlation coefficients of steroid concentrations between saliva and serum. The secondary objective was to obtain a standard diurnal rhythm of salivary cortisol and DHEA in the Korean population. MATERIALS AND METHODS: For the first objective, saliva and blood samples were collected between 10 and 11 AM from 359 volunteers ranging from 21 to 69 years old (167 men and 192 women). For the second objective, four saliva samples (post-awakening, 11AM, 4PM, and bedtime) were collected throughout a day from 78 volunteers (42 women and 36 men) ranging from 20 to 40 years old. Cortisol and DHEA levels were measured using a radioimmunoassay (RIA). RESULTS: The morning cortisol and DHEA levels, and the age-related steroid decline patterns were similar in both genders. Serum cortisol levels significantly decreased around forty years of age (p < 0.001, when compared with people in their 20s), and linear regression analysis with age showed a significant declining pattern (slope= -2.29, t= -4.297, p < 0.001). However, salivary cortisol levels did not change significantly with age, but showed a tendency towards decline (slope= -0.0078, t= -0.389, p=0.697). The relative cortisol ratio of serum to saliva was 3.4 - 4.5% and the ratio increased with age (slope=0.051, t=3.61, p < 0.001). DHEA levels also declined with age in saliva (slope= -0.007, t= -3.76, p < 0.001) and serum (slope= -0.197 t= -4.88, p < 0.001). In particular, DHEA levels in saliva and serum did not start to significantly decrease until ages in the 40s, but then decreased significantly further at ages in the 50s (p < 0.001, when compared with the 40s age group) and 60s (p < 0.001, when compared with the 50 age group). The relative DHEA ratio of serum to saliva was similar throughout the ages examined (slop = 0.0016, t = 0.344, p = 0.73). On the other hand, cortisol and DHEA levels in saliva reflected well those in serum (r = 0.59 and 0.86, respectively, p < 0.001). The highest salivary cortisol levels appeared just after awakening (about two fold higher than the 11 AM level), decreased throughout the day, and reached the lowest levels at bedtime (p < 0.001, when compared with PM cortisol levels). The highest salivary DHEA levels also appeared after awakening (about 1.5 fold higher than the 11 AM level) and decreased by 11AM (p < 0.001). DHEA levels did not decrease further until bedtime (p=0.11, when compared with PM DHEA levels). CONCLUSION: This study showed that cortisol and DHEA levels change with age and that the negative slope of DHEA was steeper than that of cortisol in saliva and serum. As the cortisol and DHEA levels in saliva reflected those in serum, the measurement of steroid levels in saliva provide a useful and practical tool to evaluate adrenal functions, which are essential for clinical diagnosis.
Adult ; Age Factors ; Aged ; Analysis of Variance ; *Circadian Rhythm ; Dehydroepiandrosterone/blood/*metabolism ; Female ; Humans ; Hydrocortisone/blood/*metabolism ; Male ; Middle Aged ; Saliva/*metabolism

PURPOSE: The primary objective of this study was to examine the changes of basal cortisol and DHEA levels present in saliva and serum with age, and to determine the correlation coefficients of steroid concentrations between saliva and serum. The secondary objective was to obtain a standard diurnal rhythm of salivary cortisol and DHEA in the Korean population. MATERIALS AND METHODS: For the first objective, saliva and blood samples were collected between 10 and 11 AM from 359 volunteers ranging from 21 to 69 years old (167 men and 192 women). For the second objective, four saliva samples (post-awakening, 11AM, 4PM, and bedtime) were collected throughout a day from 78 volunteers (42 women and 36 men) ranging from 20 to 40 years old. Cortisol and DHEA levels were measured using a radioimmunoassay (RIA). RESULTS: The morning cortisol and DHEA levels, and the age-related steroid decline patterns were similar in both genders. Serum cortisol levels significantly decreased around forty years of age (p < 0.001, when compared with people in their 20s), and linear regression analysis with age showed a significant declining pattern (slope= -2.29, t= -4.297, p < 0.001). However, salivary cortisol levels did not change significantly with age, but showed a tendency towards decline (slope= -0.0078, t= -0.389, p=0.697). The relative cortisol ratio of serum to saliva was 3.4 - 4.5% and the ratio increased with age (slope=0.051, t=3.61, p < 0.001). DHEA levels also declined with age in saliva (slope= -0.007, t= -3.76, p < 0.001) and serum (slope= -0.197 t= -4.88, p < 0.001). In particular, DHEA levels in saliva and serum did not start to significantly decrease until ages in the 40s, but then decreased significantly further at ages in the 50s (p < 0.001, when compared with the 40s age group) and 60s (p < 0.001, when compared with the 50 age group). The relative DHEA ratio of serum to saliva was similar throughout the ages examined (slop = 0.0016, t = 0.344, p = 0.73). On the other hand, cortisol and DHEA levels in saliva reflected well those in serum (r = 0.59 and 0.86, respectively, p < 0.001). The highest salivary cortisol levels appeared just after awakening (about two fold higher than the 11 AM level), decreased throughout the day, and reached the lowest levels at bedtime (p < 0.001, when compared with PM cortisol levels). The highest salivary DHEA levels also appeared after awakening (about 1.5 fold higher than the 11 AM level) and decreased by 11AM (p < 0.001). DHEA levels did not decrease further until bedtime (p=0.11, when compared with PM DHEA levels). CONCLUSION: This study showed that cortisol and DHEA levels change with age and that the negative slope of DHEA was steeper than that of cortisol in saliva and serum. As the cortisol and DHEA levels in saliva reflected those in serum, the measurement of steroid levels in saliva provide a useful and practical tool to evaluate adrenal functions, which are essential for clinical diagnosis.
Adult ; Age Factors ; Aged ; Analysis of Variance ; *Circadian Rhythm ; Dehydroepiandrosterone/blood/*metabolism ; Female ; Humans ; Hydrocortisone/blood/*metabolism ; Male ; Middle Aged ; Saliva/*metabolism

Animals ; Aorta ; pathology ; Atherosclerosis ; blood ; etiology ; metabolism ; Chemokine CCL2 ; metabolism ; Cholesterol ; blood ; Cholesterol, Dietary ; administration & dosage ; Cholesterol, HDL ; blood ; Cholesterol, LDL ; blood ; Dehydroepiandrosterone ; pharmacology ; Diet, Atherogenic ; Immunohistochemistry ; Rabbits ; Random Allocation ; Triglycerides ; blood ; Vascular Cell Adhesion Molecule-1 ; metabolism

To investigate the relationship between the insulin resistance (IR) of polycystic ovarian syndrome (PCOS) rat model induced by dehydroeplandrosterone (DHEA) and hormonal changes in the ovarium and the resistin mRNA levels in adipose tissue, 21-day-old female SD rats were divided into two groups in pairs. The rats in group 1 were injected daily (s.c.) with DHEA for up to 20 days and the rats in group 2 injected with oil at the same time. Ovarian weight, serum insulin levels and sex hormone levels in rat blood of both groups were determined. Oral glucose tolerance tests, light microscopic and electronic microscopic examination were performed. The levels of resistin mRNA in adipose tissue were measured by reverse transcription-polymerase chain reaction (RT-PCR). Our results showed that the ovarian weight in group 1 was greater than that in group 2 (P<0.05). The ovaria in group 1 showed multiple follicular cysts, The serum testeosterone and etrasdiol concentration were significantly higher in group 1 than those in group 2 (P<0.001 and P<0.05 respectively), so as the fasting serum glucose (P<0.001) and fasting serum insulin (P<0.05). The value of 1/FINS x FGC was significantly higher in group 1 than that in group 2 (P<0.001). Moreover, the resistin mRNA level of white adipose tissue in the DHEA-induced group was significantly higher than that in the control rats (P<0.05). It is concluded that the DHEA-induced PCOS rat models were similar to those of the patients with PCOS, and the IR was observed. Resistin secreted by adipose tissue may mediate IR in PCOS, and it is likely involved in the pathogenesis and development of PCOS.
Adipose Tissue ; metabolism ; Animals ; Animals, Newborn ; Dehydroepiandrosterone ; Estradiol ; blood ; Female ; Insulin Resistance ; Polycystic Ovary Syndrome ; chemically induced ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Sprague-Dawley ; Resistin ; biosynthesis ; genetics ; Testosterone ; blood

AIMTo examine the inter-relationships among age, lifestyle factors, anthropometric parameters, percent body fat and steroid hormone parameters in 531 healthy Singaporean Chinese men aged between 29 and 72 years old.

METHODSVarious lifestyle parameters were quantified through a survey, and testosterone (T), estradiol (E2), dehydroepiandrosterone sulphate (DHEAS) and sex hormone binding globulin (SHBG) were measured using established methods. Anthropometric parameters were collected and computed, and percent body fat (Siri) was measured using the DEXA scanner.

RESULTSSHBG, DHEAS, bioavailable-T (Bio-T), E2, Siri, Ht, W/H, W/Ht and work stress were independently correlated with age. Using multivariate analyses and adjusting for age and other related factors, exercise, smoking and alcohol consumption have positive impacts on androgen levels and body composition. However, black and green tea consumption was associated with negative effects on body composition and with higher levels of E2 and Free Estradiol Index (FEI). Men with shorter sleep duration had significantly lower T levels as compared to those with 6 h or more of nightly sleep. Higher T levels were associated with lower levels of adiposity and other indices of adiposity, whereas higher E2 levels were related to higher levels of adiposity. Men with higher DHEAS were significantly taller and heavier than those with low DHEAS levels.

CONCLUSIONThe study showed the close interactions among the gonadal/adrenal and metabolic compartments, with age being a key determinant in their interactions. Lifestyle factors such as exercise, smoking, sleeping and alcohol and tea consumption might play significantly roles in determining the status of health in men.

Adipose Tissue ; anatomy & histology ; Adult ; Age Distribution ; Aged ; Body Weight ; Dehydroepiandrosterone ; blood ; Demography ; Estradiol ; blood ; Hormones ; blood ; Humans ; Life Style ; Male ; Middle Aged ; Oxygen Consumption ; Physical Fitness ; Reference Values ; Sex Hormone-Binding Globulin ; metabolism ; Singapore ; Stress, Physiological ; physiopathology ; Testosterone ; blood ; Walking