Biomedical subjects

K Salminen

Publications and source records attributed to K Salminen.

At least 37 records · Page 2Linked to original sources

PubMed1988

Beta-endorphin and corticotropin release is dependent on a threshold intensity of running exercise in male endurance athletes.

Relationship between the intensity of running exercise on a treadmill and the changes in the concentrations of beta-endorphin + beta-lipotropin (beta-E + beta-LPH) and adrenocorticotropic hormone (ACTH) in plasma were studied in 10 experienced male endurance athletes. At random order, the subjects run on a treadmill six exercises which required on an average (mean +/- S.E.) 50 +/- 0.8%, 58 +/- 0.8%, 69 +/- 1.1%, 80 +/- 0.7%, 92 +/- 1.0% and 98 +/- 0.5% of their maximal oxygen consumption. Plasma levels of beta-E + beta-LPH and ACTH did not show any significant changes during the 50-80%-tests. During the 92% test, the mean levels (+/- S.E.) of beta-E + beta-LPH and ACTH increased significantly (p less than 0.001), from 3.0 +/- 0.4 to 8.0 +/- 1.2 pmol/l and from 3.1 +/- 0.5 to 8.9 +/- 1.3 pmol/l, respectively, and during the 98% test, from 3.7 +/- 0.6 pmol/l to 20.4 +/- 1.5 pmol/l, and from 3.6 +/- 0.6 to 21.8 +/- 1.5 pmol/l, respectively. Increases in the plasma levels of beta-E + beta-LPH and ACTH were always accompanied by an increase in the blood lactate level. We conclude that intensive running with an anaerobic response causes an increase in the concentrations of beta-endorphin and ACTH in plasma in endurance athletes, whereas slight aerobic exercise did not elicit any response.

Adrenocorticotropic Hormone↗

PubMed1988

Plasma corticotropin-releasing hormone, corticotropin, and endorphins at rest and during exercise in eumenorrheic and amenorrheic athletes.

The hypothalamic-pituitary response to exercise was studied in 12 amenorrheic and in 9 eumenorrheic athletes by comparing the concentrations of corticotropin-releasing hormone (CRH), corticotropin (ACTH), and endorphins (beta-endorphin + beta-lipotropin) in plasma at rest and during an acute exercise on a bicycle ergometer requiring 80% and 100% of the maximal oxygen uptake (VO2 max). Plasma CRH levels did not change during the exercise, and the mean CRH values did not differ between the amenorrheic and eumenorrheic groups. In both groups, significant increases in the response to exercise were found in the concentrations of ACTH and endorphins. The only significant difference between the groups was a larger mean pre-exercise concentration of endorphins in amenorrheic than in eumenorrheic athletes (4.8 +/- 0.8 standard error [SE] and 2.9 +/- 0.2 pmol/l, respectively). It is concluded that in amenorrheic athletes the capacity of the anterior pituitary to secrete ACTH and endorphins in response to exercise does not significantly differ from that in eumenorrheic athletes, although basal endorphin secretion may be increased.

Adolescent↗

PubMed1987

Plasma beta-endorphin, beta-lipotropin and corticotropin in polycystic ovarian disease.

In 9 women with polycystic ovarian disease (PCOD) and in 11 control subjects at the follicular phase of the normal cycle, blood samples were collected at 15-min intervals during a 2 h period of bed rest for the assay of beta-endorphin, beta-lipotropin, corticotropin, cortisol and prolactin. During the study period, the plasma levels of these hormones decreased more significantly in the PCOD than in the control group, suggesting that the PCOD patients had a more significant stress response to the puncture of the vein than the control subjects. The second hour of the study period was considered to represent resting levels of hormones. The mean resting levels (+/- S.E.) of the hormones between the PCOD and control groups, respectively, were as follows: beta-E, 2.0 +/- 0.4 vs. 1.1 +/- 0.1 pmol/l, p less than 0.05; beta-LPH, 3.4 +/- 0.6 vs. 2.1 +/- 0.5 pmol/l, N.S.; corticotropin, 2.0 +/- 0.3 vs. 1.1 +/- 0.5 pmol/l, p less than 0.05; cortisol, 176 +/- 24 vs. 128 +/- 16, N.S.; and prolactin; 3.9 +/- 0.6 vs. 5.6 +/- 1.2 ng/ml, N.S. These results confirm the previous findings on increased circulating levels of beta-E in PCOD. A concomitant increase of the plasma level of corticotropin suggests that the basal secretion of both beta-E and corticotropin from the anterior pituitary gland is increased in women with PCOD.

Adrenocorticotropic Hormone↗

PubMed1987

Plasma endogenous opioids and dexamethasone suppression test in depression.

Plasma levels of beta-endorphin plus beta-lipotropin were determined in 35 hospital patients with depression and in 23 controls before and after administration of 1 mg of dexamethasone (dxm). Dxm suppressed opioid secretion in both groups. The opioid levels of the patients were significantly higher than those of the controls both before and after dxm. All the controls were cortisol suppressors. Among the patients the post-dxm opioid levels of cortisol nonsuppressors (n = 14) were higher than those of cortisol suppressors (n = 21). A significant correlation between the opioid and cortisol levels was found in the patients. There was a significant association between the use of neuroleptics and high opioid levels, but the difference between the patients and the controls was not explained by the effect of any single class of drugs. The results support the concept of hypersecretion of corticotropin-releasing factor in depression.

Adult↗

PubMed1987

Plasma beta-endorphin immunoreactivity in premenstrual tension.

Plasma samples were collected twice during the follicular phase and three times during the luteal phase of the menstrual cycle in 12 women with premenstrual tension (PMT) and in 14 control subjects without symptoms. Concentrations of beta-endorphin (beta-E) immunoreactivity, cortisol, oestradiol, progesterone and LH were determined. Comparison of the mean concentrations of LH, cortisol, oestradiol and progesterone did not reveal any statistically significant differences between the PMT and the control groups. In the early luteal phase, the mean plasma beta-E immunoreactivity was lower in the PMT group (10.7, SE 0.7 pg/ml) than in the control group (14.6, SE 1.6 pg/ml, P less than 0.05), suggesting that endorphin secretion is decreased in PMT. No significant change in the plasma beta-E level was found in the PMT patients between the follicular and luteal phase when symptoms appeared. This does not exclude the possibility that in the central nervous system abnormal changes occur in the activity of endogenous opioids in PMT.

Adult↗

PubMed1987

Response of plasma endorphins to running exercises in male and female endurance athletes.

We studied the responses of plasma concentrations of beta-endorphin, beta-lipotropin, and corticotropin to an exhaustive graded treadmill exercise, to an anaerobic treadmill exercise, and to a sub-maximal outdoor running exercise in 5 male and in 5 female endurance athletes. During the graded treadmill exercise, the mean plasma level (+/- SE) of beta-endorphin in men rose from 1.2 +/- 0.1 to 8.1 +/- 0.7 pmol.l-1, beta-lipotropin rose from 1.6 +/- 0.5 to 7.4 +/- 1.4 pmol.l-1, and corticotropin rose from 4.9 +/- 1.0 to 31 +/- 3.3 pmol.l-1. In women, the mean level of beta-endorphin rose from 1.2 +/- 0.2 to 8.2 +/- 1.8 pmol.l-1, beta-lipotropin rose from 1.4 +/- 0.1 to 8.1 +/- 2.0 pmol.l-1, and corticotropin rose from 3.3 +/- 0.4 to 28 +/- 7.9 pmol.l-1. Concentrations of endorphins and corticotropin increased significantly also during the anaerobic exercise test. In response to sub-maximal running exercise, no significant change was found. These results showed a relationship between the intensity of exercise and the secretion of pro-opiomelanocortin-related peptides, and there were no differences between the groups of trained men and women.

Adrenocorticotropic Hormone↗

PubMed1986

Beta-endorphin and beta-lipotrophin in human ovary.

The presence of beta-endorphin (beta-E) and beta-lipotrophin (beta-LPH) in human ovary was studied by liquid chromatography and radioimmunoassay, and by immunoperoxidase staining. The mean concentrations (+/- S.E., N=8) of beta-E and beta-LPH in follicular fluid samples collected during the late follicular phase of normal cycles were 1.9 +/- 0.4 pmol/l and 2.9 +/- 0.8 pmol/l, respectively. After hyperstimulation with clomiphene and gonadotropin for in vitro fertilization, the mean concentrations of beta-E and beta-LPH in follicular fluid did not increase significantly, being 3.2 +/- 0.6 and 4.1 +/- 1.0 pmol/l, respectively (N=13). beta-E or beta-LPH were not found in three corpora lutea analysed. Immunohistochemical staining of ovarian tissue did not reveal any beta-E immunoreactivity. Thus the origin of beta-E and beta-LPH in the follicular fluid remained unclear. In 7 women, blood samples were collected from the peripheral and ovarian veins at laparotomy. No significant concentration excess of beta-E or beta-LPH was found in the ovarian venous plasma, suggesting that human ovaries do not secrete significant amounts of beta-E or beta-LPH into the peripheral circulation. It seems that the role of endorphins in the human ovary is less significant than previously proposed for sheep, rat or mouse ovary.

Adult↗

PubMed1986

Plasma beta-endorphin in perinatal asphyxia and respiratory difficulties in newborn infants.

The effects of intrauterine stress and birth asphyxia on the plasma concentration of beta-endorphin (beta-E) in cord blood and in venous blood at the age of 2 h was investigated in newborn infants. Term infants with acute birth asphyxia (n = 11), infants born to mothers with preeclampsia (n = 15), and prematures with respiratory difficulties (n = 4) were entered into the study. Twenty control infants were studied; 12 were born after spontaneous delivery and eight after elective cesarean section. After normal spontaneous delivery, the plasma beta-E level decreased significantly, the median values being 17 pmol/liter at birth and 9.3 pmol/liter at the age of 2 h, whereas after elective cesarean section it remained unchanged (13 and 13 pmol/liter, respectively). In acute asphyxia the plasma beta-E level varied widely at birth, from 9.7 to 108 pmol/liter. At the age of 2 h, the beta-E level was high (26 to 83 pmol/liter) in those asphyctic infants who required prolonged mechanical ventilation, but it fell to the range of 1.6-13 pmol/liter when the infant recovered rapidly. The beta-E level was not increased in the preeclampsia group, not even in small for gestational age infants. In preterm newborn infants with respiratory difficulties, a significant postnatal rise of plasma beta-E level was found, the beta-E value varying from 7.3 to 16 pmol/liter at birth and from 61 to 168 pmol/liter at the age of 2 h. These results indicate that increased beta-E secretion is associated with respiratory difficulties in the newborn infant.

Apgar Score↗

PubMed1986

Release of beta-endorphin in response to physical exercise in non-pregnant and pregnant women.

The effect of physical exercise on beta-endorphin (beta-E) concentration in plasma was studied in 8 non-pregnant and in 8 pregnant women in their last trimester of pregnancy, using a 10-min bicycle ergometer test. In the non-pregnant women the mean beta-E levels were 2.4 +/- 0.7 (S.E.) pmol/l before the test, 4.3 +/- 0.9 pmol/l at the end of the test, and 4.3 +/- 0.6 and 5.0 +/- 2.0 pmol/l 15 and 30 min after the test, respectively, declining thereafter. In the pregnant women the mean beta-E values were 5.1 +/- 2.0 pmol/l before the test, 7.3 +/- 1.7 pmol/l at the end of the test, 6.7 +/- 2.0 pmol/l 15 min after the test, and 12.6 +/- 4.1 pmol/l 60 min after the test, declining thereafter. Thus, beta-E secretion increased in response to exercise both in non-pregnant and in pregnant women, the response lasting longer in pregnant women.

Adult↗

PubMed1986

Beta-endorphin in maternal and umbilical cord plasma at elective cesarean section and in spontaneous labor.

Concentration of beta-endorphin in relation to the mode of delivery and anesthesia was studied in maternal and umbilical cord plasma in 30 healthy women at term pregnancy. At elective cesarean section under epidural anesthesia, the mean maternal beta-endorphin level rose from 9.8 +/- 2.7 pmol/L (SE) before induction to 15.5 +/- 3.7 pmol/L at the time of delivery (P less than .02). Under general anesthesia the mean beta-endorphin level increased more, from 14.6 +/- 7.2 to 34.4 +/- 7.8 pmol/L (P less than .02), reaching the mean beta-endorphin value of the second stage of normal labor, 39.4 +/- 7.0 pmol/L. In the cord arterial and venous plasma, the mean beta-endorphin value was significantly higher after spontaneous labor (40.9 +/- 11 and 40.1 +/- 9.2 pmol/L, respectively) than at elective cesarean section under epidural (14.3 +/- 1.9 and 12.4 +/- 3.6 pmol/L, respectively) or general anesthesia (11.9 +/- 2.2 and 13.4 +/- 2.2 pmol/L, respectively). Thus cesarean section under general anesthesia proved to be more stressful for the mother than that under epidural anesthesia, when beta-endorphin release is used as the measure of stress. The mode of anesthesia did not seem to influence the plasma beta-endorphin level in the newborn infant. Normal delivery by vaginal route increased the release of beta-endorphin both to the maternal and the fetoplacental circulation.

Anesthesia, Epidural↗

PubMed1985

Immunoreactive beta-endorphin is demonstrable in the secretory but not in the proliferative endometrium.

The presence of immunoreactive beta-endorphin (ir beta-E) in the endometrium was studied by immunoperoxidase staining of tissue sections at various stages of the menstrual cycle. Ir beta-E was found in the endometrium during the secretory phase of the cycle, from the fourth postovulatory day to the desquamating phase, but not in the proliferative phase or during the first three postovulatory days of the cycle. Ir beta-E was located in the cytoplasm of the epithelial cells of the glands. Samples of endometrium were homogenized, and peptides were extracted with Sep Pak C18 cartridge, followed by purification of ir beta-E by cation-exchange high-pressure liquid chromatography. In samples of secretory endometrium, a peak of ir beta-E was found with identical location of that of reference beta-E. The concentration of ir beta-E in the secretory endometrium varied from 5.0 to 12.6 pg/g of tissue. The appearance of ir beta-E in the endometrium during the secretory phase may have importance in the early events of reproduction.

Endometrium↗

PubMed1985

Determination of plasma beta-endorphin and beta-lipotropin by cation-exchange liquid chromatography and radioimmunoassay.

In this method for rapid separation of beta-endorphin (beta-EP) and beta-lipotropin (beta-LPH) in plasma, most of the plasma proteins in a 0.5- to 2.0-mL sample of plasma are precipitated with acetonitrile at pH 4.7. beta-EP and beta-LPH in the supernate are completely separated by liquid chromatography on a cation-exchange column, with gradient elution with volatile buffers, and are eluted in 1.5- to 2.0-mL volumes. After lyophilization, the redissolved beta-EP and beta-LPH are determined by radioimmunoassay. The respective mean concentrations of immunoreactive beta-EP and beta-LPH in plasma of nonpregnant women were 4.0 (SD 2.0) and 5.1 (SD 3.0) pmol/L; during labor, 33.3 (SD 25) and 69.6 (SD 41) pmol/L; and in venous plasma from umbilical cords after spontaneous labor, 38.6 (SD 18) and 38.7 (SD 19) pmol/L.

Acetonitriles↗

PubMed1985

Plasma beta-endorphin and the menstrual cycle.

beta-Endorphin (beta-E) takes part in the regulation of luteinizing hormone (LH) and prolactin secretion, but little is known about its role in the menstrual cycle. Using a specific assay, plasma concentration of beta-E was followed in healthy women in the periovulatory period and before and during menstruation. The mean concentration of beta-E in the eight women studied showed an increase at the midcycle, being 3.2 +/- 0.5 (standard error) pmol/l on day LH -1 and rising to 4.6 +/- 0.7 pmol/l on day LH 0 and further to 7.5 +/- 1.2 pmol/l on day LH +1. Thereafter, the mean beta-E level remained at 5.3 +/- 0.8 pmol/l and 5.2 +/- 0.4 pmol/l on days LH +2 and LH +3, respectively. Ten additional women were studied before and during menstruation. The highest mean plasma concentration of beta-E, 5.1 +/- 0.9 pmol/l, was found at the onset of menstruation, declining to 3.3 +/- 0.6 pmol/l and 2.9 +/- 0.6 pmol/l on the second and fifth days of menstruation, respectively. These findings suggest that beta-E secretion increases at the time of ovulation. At the onset of menstruation, pain may increase endorphin secretion.

Adult↗

PubMed1985

Tocopherols and tocotrienols in Finnish foods: human milk and infant formulas.

Individual tocopherols and tocotrienols in human milk, mother's milk substitutes and other infant formulas have been determined by an HPLC method. 107 human milk samples (23 colostral, 22 transitional and 62 mature) obtained from six healthy mothers throughout the lactation were found to contain all the tocopherols, although delta-tocopherol occurred only in traces. A high content of alpha-tocopherol was found in colostrum (average 1.90 +/- 1.62 (SD) mg/100 g), as compared with transitional (0.65 +/- 0.22 mg/100 g) and mature milk (0.47 +/- 0.16 mg/100 g). The content of beta-tocopherol averaged 0.05 +/- 0.03, 0.02 +/- 0.01 and 0.02 +/- 0.01 and gamma-tocopherol 0.11 +/- 0.09, 0.07 +/- 0.04 and 0.07 +/- 0.04 mg/100 g in colostral, transitional and mature milk respectively. The alpha-tocopherol equivalents thus were 1.93, 0.66 and 0.49 mg/100 g; their ratios to the contents of polyunsaturated fatty acids meet the nutritional need of the newborn and young infant: 5.7, 2.1 and 1.4 mg/g in colostral, transitional and mature milk. Mother's milk substitutes and gruel and porridge powders are enriched with tocopherol acetate to vitamin E levels similar to or higher than those in human milk: substitutes contained on average 1.4 mg alpha-tocopherol equivalents/100 g and reconstituted powders 1.1 mg/100 g. The ratio of vitamin E to polyunsaturated fatty acids of these infant formulas was higher than the recommended value of 0.6 mg/g. The average values for alpha-tocopherol equivalents in fruit-berry and meat-vegetable infant formulas were 0.46 and 0.38 mg/100 g.

Colostrum↗

PubMed1984

Rapid extraction and separation of plasma beta-endorphin by cation-exchange high-performance liquid chromatography.

Cation-exchange high-performance liquid chromatography (HPLC) was used to increase the sensitivity and specificity of the radioimmunoassay of plasma beta-endorphin. Proteins were precipitated from a 0.5 to 2.5 ml sample of plasma with 60% acetonitrile at pH 4.7. The supernatant was subjected to cation-exchange HPLC. Gradient elution with volatile buffers was used to separate beta-endorphin from beta-lipotropin. The beta-endorphin fraction (1.8 ml) was concentrated by lyophilization and subjected to radioimmunoassay. In healthy pregnant women at labour plasma concentration of beta-endorphin varied from 105 to 403 pg/ml. In healthy non-pregnant women plasma concentration of beta-endorphin was low, exceeding the detection limit (4 pg/ml) of the assay in only one of the 7 subjects studied.

Chromatography, High Pressure Liquid↗

PubMed1984

Pain and plasma beta-endorphin level during labor.

Plasma concentration of beta-endorphin was observed during labor in 16 women and correlated with pain assessed subjectively using pain scores. Ten women did not receive any medication during the follow-up. A concomitant increase in pain score and plasma beta-endorphin level was found with advancing labor. In the remaining six women, epidural anesthesia was used to relieve pain. During epidural anesthesia, plasma beta-endorphin levels and pain scores decreased concomitantly. The same effect was found after a repeated dose of the anesthetic. These findings showed a correlation between pain and the secretion of beta-endorphin during labor, but the mode of action of beta-endorphin remains unsolved.

Adult↗

PubMed1984

High-performance liquid chromatographic determination of tocopherols and tocotrienols and its application to diets and plasma of Finnish men. I. Analytical method.

A HPLC Method is described for the determination of tocopherols and tocotrienols in human diets and plasma. After a room-temperature saponification diet samples were extracted with n-hexane. A direct hexane extraction was used for plasma samples. Using a normal-phase column at elevated temperature and a fluorescence detector complete separation of all four tocopherols, alpha-, beta-, gamma-tocotrienols and BHA and good reproducibility and sensitivity were obtained. The recovery of tocopherols added to diet samples was 99% for alpha-tocopherol, 95% for beta-tocopherol, 99% for gamma-tocopherol and 80% for delta-tocopherol. The recovery of alpha-tocopherol added into plasma was 99%.

Butylated Hydroxyanisole↗

PubMed1984

High-performance liquid chromatographic determination of tocopherols and tocotrienols and its application to diets and plasma of Finnish men. II. Applications.

The composed one-day diets and plasma of 40 Finnish men screened for a selenium supplementation study were analyzed for tocopherols and tocotrienols. The men were divided into a low-Se group (in the screening phase plasma Se levels less than 70 micrograms/l and plasma alpha-tocopherol levels less than 1.2 mg/100 ml) and a high-Se group (plasma Se greater than 70 micrograms/l, plasma alpha-tocopherol not determined before the study). In the low-Se group plasma levels of alpha-tocopherol averaged 0.97 +/- 0.18 mg/100 ml. The daily dietary intake of alpha-tocopherol was 6.1 +/- 2.7 mg and that of total vitamin E 7.3 +/- 3.1 mg of alpha-tocopherol equivalents. In the high-Se group the corresponding average values were 1.16 +/- 0.21 mg of alpha-tocopherol/100 ml of plasma, 8.8 +/- 4.3 mg of alpha-tocopherol/day and 10.3 +/- 5.1 mg of alpha-tocopherol equivalents/day. The overall average for the contribution of alpha-tocopherol to the total dietary tocopherols was 44.6 +/- 11.0%. In the plasma samples alpha-tocopherol accounted for 92.0 +/- 2.1%, beta-tocopherol for 2.7 +/- 0.7% and gamma-tocopherol for 5.3 +/- 2.1% of the total amount of tocopherols.

Canada↗