Search results for "HORMONES"

Distribution and coexistence of chromogranin A-, serotonin-and pancreastatin-like immunoreactivity in endocrine-like cells of the human anal canal

1992

The comparative distribution and coexistence of chromogranin A (CGA)-, serotonin (5-hydroxytryptamine; 5-HT)- and pancreastatin (PST)-like immunoreactivity in endocrine-like cells of the human anal canal was investigated by light-microscopic immunocytochemistry. The largest population of colorectal endocrine-like cells consisted of CGA-immunoreactive (ir) cells, followed by the 5-HT-ir and PST-ir cell population. In the anal transitional zone (ATZ), CGA- and 5-HT-immunoreactivity was equally distributed; ir-PST was confined to a smaller endocrine-like cell population. In the squamous zone and the perianal skin, Merkel cells in the basal layer of the epidermis and hair follicles exhibited ir…

Differential Effects of Fluvoxamine and Other Antidepressants on the Biotransformation of Melatonin

2001

Melatonin, the predominant product of the pineal gland, is involved in the maintenance of diurnal rhythms. Nocturnal blood concentrations of melatonin have been shown to be enhanced by fluvoxamine, but not by other serotonin reuptake inhibitors. Because fluvoxamine is an inhibitor of several cytochrome P450 (CYP) enzymes, the authors studied the biotransformation of melatonin and the effects of fluvoxamine on the metabolism of melatonin in vitro using human liver microsomes and recombinant human CYP isoenzymes. Melatonin was found to be almost exclusively metabolized by CYP1A2 to 6-hydroxymelatonin and N-acetylserotonin with a minimal contribution of CYP2C19. Both reactions were potently in…

A GC-MS method for hormone analysis and modulation of ovarian histology and steroidogenic genes by TBT and Bisphenol-A in Ciona intestinalis

2009

Sex hormone profiles in Ciona intestinalis (Ascidiacea Urochordata) and their modulation by Tributyltin (TBT)

2008

Screening of Ovarian steroidogenic pathway in Ciona intestinalis and its modulation after Tributyltin exposure

2010

In this study, we have identified several ovarian steroids in Ciona with high similarity to vertebrate steroids and showed that cholesterol, corticosterone, dehydroepiandrosterone, estrone, estradiol-17beta, testosterone, pregnenolone, progesterone, have identical molecular spectra with vertebrate steroids. In addition, we have studied the effects of an endocrine disruptor (tributyltin: TBT) on these sex hormones and their precursors, ovarian morphology, and gene expression of some key enzymes in steroidogenic pathway in the ovary of Ciona. Ovarian specimens were cultured in vitro using different concentrations of TBT (10{sup -5}, 10{sup -4} and 10{sup -3} M). Ethanol was used as solvent co…

Modifications of atrial natriuretic peptide and vasopressin peptides in the rat hypothalamic supraoptic nucleus during resistance training

2010

Many studies have demonstrated the involvement of atrial natriuretic peptide (ANP) and vasopressin (VP) in the homeostasis of body fluids, but few studies have regarded the hypothalamic magnocellular neurosecretory system during physical exercises. The aim of the present immunohistochemical work is to study the activity of ANP and VP secreting neurons of the hypothalamic supraoptic nucleus during and after resistance training. The study was carried out in Wistar rats trained by a physical resistance-type exercise, using a rung ladder and a varying load fastened to the tail of each rat; the exercise lasted 20 min everyday for periods of 15, 30 and 45 days. Animal groups were sacrificed at th…

Atrial Natriuretic Peptide presence in parotid gland of human fetus at 13th week of development and in adult man

2013

Our immunohistochemical study shows that atrial natriuretic peptide (ANP) is present in both human fetal and adult parotid gland. In the fetuses ANP is localized in cell clusters, while in adult parotid gland, the ANP is seen only in the wall of intra- and extralobular ducts. The results suggest that ANP might play a role in the differentiation of the parotid gland similarly as in brain and that during fetal growth ANP may play a role in the regulating the secretion of primitive salivary fluid, even if acini are still not developed. (Folia Histochemica et Cytobiologica 2013, Vol. 51, No. 1, 55-58)

Human umbilical cord expresses several vasoactive peptides involved in the local regulation of vascular tone: protein and gene expression of Orphanin…

2011

Full-term human umbilical cord contains three blood vessels: two arteries coiled around a vein and surrounded by Wharton’s jelly, a mucous tissue with few mesenchymal stromal cells and abundant extracellular matrix. Umbilical vessels lack innervations, thus endothelial cells must play a role in the control of blood flow. The aim of this study was to investigate in human umbilical cord the expression of five peptides that could be involved in the regulation of vascular tone: Orphanin FQ, Oxytocin, Atrial Natriuretic Peptide (ANP), endothelial Nitric Oxide Synthase (eNOS) and inducible Nitric Oxide Synthase (iNOS). The expression of these molecules in full-term human umbilical cord …

Atrial natriuretic peptide (ANP) and oxytocin-expression in the adult rat and mouse cerebellum.

2015

Abstract Background: Many studies are in the literature on the ANP and oxytocin-presence in the brain, but very few studies with controversial results are reported on the presence of these peptides in the cerebellum. This immunohistochemical study investigates on the ANP and oxytocin-presence in the cerebellum of the adult rat and mouse rodents. Results: This study, firstly, evidences the ANP- immunopositivity in cerebellar cortex of both rat and mouse rodents. In rat the molecular layer presents some few immunopositive fibers, but no neuron resulted immunopositive; the granular and Purkinje cells are immunopositive. In mouse the cerebellar cortex ANP-immunopositivity is present in all laye…

MAGNESIUM AND ANABOLIC HORMONES IN OLDER MEN

2011

Optimal nutritional and hormonal statuses are determinants of successful age-ing. The age associated decline in anabolic hormones such as testosterone and insulin-like growth factor 1 (IGF-1) is a strong predictor of metabolic syn-drome, diabetes and mortality in older men. Studies have shown that magne-sium intake affects the secretion of total IGF-1 and increase testosterone bioactivity. This observation suggests that magnesium can be a modulator of the anabolic ⁄ catabolic equilibrium disrupted in the elderly people. However, the relationship between magnesium and anabolic hormones in men has not been investigated. We evaluated 399 ‡65-year-old men of CHIANTI in a study population repres…