Plasma hormones

M (reduced testicular and plasma hormones, decreased enzyme activity levels)... 

DUNCAN M, MERZ-DEMLOW E, XU X, PHIPPS w R and KURZER M s (2000) Premenopausal equol excretors show plasma hormone profiles associated with lowered risk of breast cancer. Cancer Epidemiol Biomarkers Prev 9, 581-6. 

Plasma hormones and enzymes of testicular origin were used as markers for evaluation of acute testicular toxicity in rats treated with 1,3-DNB. Lactate dehydrogenase isozyme C4 (LDH-C4) and ABP were both elevated after treatment with doses between 10 and 25 mg/kg of 1,3-DNB (Reader et al. 1991). Testosterone levels were reduced after treatment with 10 and 32 mg/kg of 1,3-DNB (Reader etal. 1991 Rehnberg et al. 1988). 

Definition of catabolic period, and the plasma hormones seen in this state... 

Biochemical measurements using blood, urine, cerebrospinal fluid, peripheral tissues such as platelets or lymphocytes, postmortem brain tissues, or plasma hormones after provoking hormone secretion by drugs... 

Winokur et al.82 infused L-tryptophan intravenously into 11 healthy male subjects and studied plasma hormone levels. Significant increases were observed in plasma growth hormone and prolactin concentrations after L-tryptophan was given compared to saline-infused controls. No alterations in cortisol or thyrotropin levels were noted. Also, in experimental animals,... 

As a result of the above, plasma hormone concentrations are normally variable (Fig. 3). Thus a single measurement of a hormone in peripheral plasma may suggest, incorrectly, that there is abnormal endocrine function. Dynamic tests have been developed to give clearer information about endocrine activity in the patient, especially those with suspected pituitary or adrenocortical disorders. 

Fig. 2 Plasma hormone concentrations throughout the female menstrual cycle.

J. Ma, N.E. Decalo, P.W. Kantoff et al. (2001). The relationship between a polymorphism in CYP 17 with plasma hormone levels and prostate cancer. Cancer Epidemiol. Biomarkers Prev. 10, 743-748. McKean-Cowdin, R., H.S. Feigelson, M.C. Pike, G.A. Coetzee, L.N. Kolonel, and B.E. Henderson... 

In designing a study in which several additional tests cannot be obtained from a single blood collection and may require more carefully timed collections (e.g., plasma hormones), it may be necessary to include additional animals in the study. Although, ideally, both hematology and plasma chemistry sample collections should be taken from the same animals, subgroups should sometimes be used for mice and these two collections allocated to the subgroups. If the volume of collected sample is smaller than the total volume required for analysis, the tests should be prioritized in order of importance (e.g., enzyme tests for hepatic injury may be analyzed first). In some laboratories, it is the practice to repeat collections from some animals when the first collection has not been sufficient for all tests. 

Rowland, N. E., B. E. Goldstein, and K. L. Robertson. 2003. Role of angiotensin in body fluid homeostasis of mice Fluid intake, plasma hormones and brain Fos. American Journal of Physiology Regulatory Integrative and Comparative Physiology 284 R 1380-1381. 

Sulzman 1983 Murphy and Campbell 1996 Arendt 1998). Periodic changes are observed for most plasma hormones and reproductive cycle hormones in particular. These hormonal changes may be short-term pulsatile changes or daily rhythms or follow longer-term cycles (see Chapter 10 Wong et al. 1983 Kempainnen and Sartin 1981 Fukuda et al. 1988 Orth, Peterson, and Drucker 1988 Nigi and Torii 1991 Torii and Nigi 1994). 

Thyroid hormones are taken into cells by facilitated diffusion or by active transport secondary to a sodium gradient (11). Once in the cell, thyroid hormones bind to cytosolic binding proteins and are not readily available for exchange with plasma hormones. Both T3 and T4 are not evenly distributed in body cells A great part of T4 is... 

Hormones transmit information from one body site to another. Transported in the bloodstream, the hormone secreted by an endocrine gland will activate biochemical processes in various "target" cells in the body that have specific reception for that hormone. Practically all hormonal secretions exhibit circadian rhythms [8], Consequently, the plasma concentration of a hormone has a peak at a characteristic time of day and a trough at another. The circadian timing system uses circadian rhythms in plasma hormone levels to transmit temporal information and ensure the internal synchronization of the multitude of rhythmic functions in various body tissues. Several researchers have shown that aberrations in circadian rhythm timing of hormones can be viewed as a biological dy sfunction[9,10,11 ]. 

Osorio, C., Carriage of circulating thyroid hormones and the estimation of total plasma hormone levels. J. Clin. Pathol., Suppl. 20, 335-343 (1967). 

There has been much speculation in the past on the nature of the circulating thyroid hormone whether it was a simple amino acid, a peptide or polypeptide of thyroxine, or thyroglobulin itself. In 1948 Taurog and Chaikoff produced a considerable amount of evidence that the plasma hormone was indeed thyroxine. Labeled plasma iodine behaved chemically in a manner identical with that of thyroxine added to plasma it was nondialyzable it was precipitated with plasma proteins with zinc hydroxide it was extractable with butanol, and it could be fractionated with carrier thyroxine by its partition between immiscible solvents. This work received confirmation from Laidlaw (1949), and it then became generally accepted that thyroxine alone was the circulating hormone. 

See also Blood and Plasma. Hormones Steroids. Immunoassays, Applications Clinical. Quality Assurance Reference Materials. 

Bradykinin, kallUBn /, Afnfn 9 Arg-Pro-Pro-Gly-Phe-Ser-Pro-Fhe-Arg, one of a group of plasma hormones called kinins. Like the other kinins, it is produced from a plasma precursor by the action of Kal-likrein (see), Bypsin (see) or Plasmin (see). It causes dilation of blood vessels (and thus a decrease of blood pressure), causes the smooth muscles of the bronchia, intestines and uterus to contract, and is a potent pain-producing agent. Lysylbradykinin has simUar activity. 

Table 1. Mean levels of plasma hormones at 16 wk and 26 wk in broiler breeders reared on either an everyday (ED) or skip a day (SKP) regimen. 

De Beer, M., J.P.McMurtry, D.M.Brocht, and C.N. Coon, 2008. An examination of the role of feeding regimens in regulating metabolism during the broiler breeder grower period. 2. Plasma hormones and metabolites. Poult. Sci. 87, 264-275. 

Radcliff, R.P., B.L. McCormack, B.A. Crooker and M.C. Lucy, 2003. Plasma hormones and expression of growth hormone receptor and insulin-like growth factor-I mRNA in hepatic tissue of periparturient dairy cows. J. Dairy Sci. 86, 3920-3926. 

Baumann, G. (1999) Growth hormone heterogeneity in human pituitary and plasma. Hormone Research, 51,2-6. 

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