Hormone multiple

Polypeptide hormones are synthesized as part of a larger precursor molecule or prohormone. Cleavage of the prohormone by specific cellular enzymes, ie, peptidases, produces the secreted form of the hormone. In some cases, multiple bioactive hormones are produced from a single prohormone. 

CeUs synthesize and secrete multiple hormones. Eor example, some ceUs in the anterior pituitary have the capacity to secrete both polypeptide hormones, ESH and LH. CeUs also can secrete different chemical classes of hormone, eg, ceUs in the adrenal meduUa synthesize and secrete the... 

The class III cytokine receptor family includes two TNE receptors, the low affinity NGE receptor and 7-ceU surface recognition sites that appear to play a role in proliferation, apoptosis, and immunodeficiency. TNE-a (- 17, 000 protein) is produced by astrocytes and microglia and can induce fever, induce slow-wave sleep, reduce feeding, stimulate prostaglandin synthesis, stimulate corticotrophin-releasing factor and prolactin secretion, and reduce thyroid hormone secretion. TNE-a stimulates IL-1 release, is cytotoxic to oligodendrocytes, and reduces myelination this has been impHcated in multiple sclerosis and encephalomyelitis. Astrocyte TNE-a receptors mediate effects on IL-6 expression and augment astrocytic expression of MHC in response to other stimulants such as lEN-y. 

Bastenie and Zylberszac, in a general article on the former subject, point out that colchicine (1) brings into mitosis all cells which are in karyo-kinetic inuninence but which normally would slowly and successively reach mitosis, and (2) stops them at this stage. This has made possible a technique which picks out cell multiplication and can be used for detecting many types of hormonal stimulation, e.g., the action of follicular hormone and other oestrogens. ... 

Terpenoids are classified according to the number of five-carbon multiples they contain. Monoterpenoids contain 10 carbons and are derived from two isopentenyl diphosphates, sesquiterpenoids contain 15 carbons and are derived from three isopentenyl diphosphates, diterpenoids contain 20 carbons and are derived from four isopentenyl diphosphates, and so on, up to triterpenoids (C30) and tetraterpenoids (C40). Monoterpenoids and sesquiterpenoids are found primarily in plants, bacteria, and fungi, but the higher terpenoids occur in both plants and animals. The triterpenoid lanosterol, for example, is the precursor from which steroid hormones are made, and the tetraterpenoid /3-carotene is a dietary source of vitamin A (Figure 27.6). 

Most GPCRs interact with and activate more than one G-protein subfamily, e.g., with Gs plus Gq/n (histamine H2, parathyroid hormone and calcitonin recqrtors), Gs plus G (luteinising hormone receptor, 32-adrenoceptor) or Gq/11 plus G12/13 (thromboxane A2, angiotensin ATb endothelin ETA receptors). Some receptors show even broader G-protein coupling, e.g., to Gi, Gq/n plus Gi n ( protease-activated receptors, lysophosphatidate and sphingosine-1-phosphate receptors) or even to all four G-protein subfamilies (thyrotropin receptor). This multiple coupling results in multiple signaling via different pathways and in a concerted reaction of the cell to the stimulus. 

The different types or classes of phytochemicals can have multiple influences on the GIT (Kitts, 1994). For example, caffeine stimulates the motor, hormonal and secretory functions (Boekmaefa/., 1999). Although many phytochemicals reduce nutrient quality or availability, traditional herbal medicines have exploited some of these characteristics to improve health. Moreover, some of the systemic responses attributed to certain phytochemicals (beneficial or detrimental) can be explained by their influences on the GIT (Carbonaro et al., 2001). To date, the most of the information about phytochemicals is focused on the reductions in the functional capacities of the GIT (the bad), or the toxic properties (the ugly). There are also numerous examples of phytochemicals that can be used to obtain desirable GIT characteristics (the... 

Nitric oxide, a vasodilatory hormone released by the endothelium, is found in higher concentrations in HF patients and provides two main benefits in HF vasodilation and neurohormonal antagonism of endothelin.9 Nitric oxide s production is affected by the enzyme inducible nitric oxide synthetase (iNOS), which is up-regulated in the setting of HF, likely due to increased levels of angiotensin II, norepinephrine, and multiple cytokines. In HF, the physiologic response to nitric oxide appears to be blunted, which contributes to the imbalance between vasoconstriction and vasodilation. 

Haack M, Beck-Sickinger AG (2007) Multiple Peptide Synthesis to Identify Bioactive Hormone Structures. 278 243-288... 

Multiple hormones may affect a single target tissue simultaneously. Therefore, the response of the target tissue depends not only on the effects of each hormone individually, but also on the nature of the interaction of the hormones at the tissue. The three types of hormone interactions include ... 

Parathyroid hormone carries out these effects through multiple mechanisms of action ... 

Korbonits, M., Goldstone, A. P., Gueorguiev, M. Grossman, A. B. (2004). Ghrelin - a hormone with multiple functions. Front. Neuroendocrinol. 25, 27-68. 

The acute CNS effects of MDMA administration are mediated by the release of monoamine transmitters, with the subsequent activation of presynaptic and postsynaptic receptor sites.40 As specific examples in rats, MDMA suppresses 5-HT cell firing, evokes neuroendocrine secretion, and stimulates locomotor activity. MDMA-induced suppression of 5-HT cell firing in the dorsal and median raphe involves activation of presynaptic 5-HT1A autoreceptors by endogenous 5-HT.4142 Neuroendocrine effects of MDMA include secretion of prolactin from the anterior pituitary and corticosterone from the adrenal glands 43 Evidence supports the notion that these MDMA-induced hormonal effects are mediated via postsynaptic 5-HT2 receptors in the hypothalamus, which are activated by released 5-HT. MDMA elicits a unique profile of locomotor effects characterized by forward locomotion and elements of the 5-HT behavioral syndrome such as flattened body posture, Straub tail, and forepaw treading.44 6 The complex motor effects of MDMA are dependent on monoamine release followed by activation of multiple postsynaptic 5-HT and DA receptor subtypes in the brain,47 but the precise role of specific receptor subtypes is still under investigation. 

---