results the results indicated that ghrelin significantly decreased thyroid hormone concentrations, whereas estradiol increased these concentrations. the simultaneous injection of ghrelin and estradiol significantly decreased the inhibitory effect of ghrelin on thyroid hormone concentrations (p < 0.05). conclusions according to the results of this study, both ghrelin and estradiol affect the con...

Although most circulating iron in blood plasma is destined for erythropoiesis, the mechanisms by which erythropoietic demand modulates the iron supply ("erythroid regulators") remain largely unknown. Iron absorption, plasma iron concentrations, and tissue iron distribution are tightly controlled by the liver-produced hormone hepcidin. During the last decade, much progress has been made in eluci...

A substance immunochemically cross-reactive with insulin (SICRI) appears in melanoma B16 growing in diabetic and nondiabetic C57BL/6 mice. Progression of tumor size is paralleled by the increase of SICRI levels in the serum of both diabetic and nondiabetic animals; this increase correlates with a decreased concentration of circulating glucose and an elevated concentration of growth hormone in b...

To evaluate a theoretical model for calculating free thyroid hormones, based on the law of mass action, we compared values for both calculated and measured free thyroxin and free triiodothyronine in a group of normal subjects. To determine whether the concentrations of circulating free hormones were also predictable from equilibrium considerations in abnormal states, we compared calculated and ...

In most vertebrates, production of reproductive hormones wanes with age, co-occurring with a decline in reproductive output. Measurement of these hormones can serve as a key marker of the onset of reproductive senescence. Longitudinal studies of physiological parameters in populations of free-living animals are relatively uncommon; however, we have monitored baseline concentrations of hormones ...

Hormone replacement therapy (HRT) in postmenopausal women suppresses the increase in bone resorption expected as circulating levels of endogenous estrogen decline. We tested the hypothesis that bone lead content might remain elevated in women on HRT. Fifty six women who at recruitment were on average 35 years postmenopausal were placed on calcium supplementation. Six months later 33 of these wo...

Previous studies of the relationship between the endogenous opioid system and alcohol consumption have reported contradictory results. To shed light on this connection, we compared plasma concentrations of beta-endorphin, adrenocorticotropic hormone, and cortisol in 70 alcoholic persons after different periods of abstinence and a group of 80 control subjects. Plasma beta-endorphin was decreased...

A substance immunochemically cross-reactive with insulin (SICRI) appears in melanoma B16 growing in diabetic and nondiabetic CS7BL/6 mice. Progression of tumor size is paralleled by the increase of SICRI levels in the serum of both diabetic and nondiabetic animals; this increase correlates with a decreased concentration of circulating glucose and an elevated concentration of growth hormone in b...