Search results for "Endocrine System"
showing 10 items of 1530 documents
Effect of chronic citalopram on serotonin-related and stress-regulated genes in the dorsal raphe nucleus of the rat
2007
Using a model of depression in which chronic social stress induces depressive-like symptoms, we investigated effects of the selective serotonin-reuptake inhibitor (SSRI) citalopram on gene expression in the dorsal raphe nucleus of male rats. Expression of tryptophan hydroxylase (TPH) protein was found to be upregulated by the stress and normalized by citalopram, while mRNAs for genes TPH 1 and 2 were differentially affected. Citalopram had no effect on serotonin transporter mRNA but reduced serotonin-1A autoreceptor mRNA in stressed animals. The SSRI prevented the stress-induced upregulation of mRNA for CREB binding protein, synaptic vesicle glycoprotein 2b and the glial N-myc downstream-re…
Influence of melatonin and serotonin on the number of rat pineal ?synaptic? ribbons and spherules in vitro
1985
Previous studies have shown that the "synaptic" ribbons (SR) and spherules (SS) of the mammalian pineal gland may respond differently under physiological and various experimental conditions. The aim of the present study was to gain insight into the mechanisms that may be responsible for the numerical changes of these organelles during a 24-h cycle. As the possibility exists that the structures are influenced by substances synthesized within the pinealocyte, rat pineal glands were cultured with and without added melatonin or serotonin, using an experimental protocol such that the addition of melatonin and serotonin mimicks the circadian changes of the respective substances within the pineal.…
p-Chlorophenylalanine treatment depresses the number of synaptic ribbon profiles in the rat pineal gland, but does not abolish their day-night rhythm
1995
It is largely unknown as to how the day/night rhythm of pineal synaptic ribbon number is regulated. Transcriptional events related to the nocturnal formation of new synaptic ribbons occur early in the morning, when pineal serotonin levels begin to increase. The present study was carried out in order to elucidate as to how altered serotonin levels affect the day/night changes in the number of synaptic ribbon profiles. To this end, male Sprague-Dawley rats received a single dose of p-chlorophenylalanine (pCPA, 300 mg/kg body weight, 72 hours before sacrifice), which depresses tryptophan hydroxylase activity and hence pineal serotonin levels. Control animals received saline injections. Experim…
The use of statins in people at risk of developing diabetes mellitus: Evidence and guidance for clinical practice
2014
Reducing low-density lipoprotein cholesterol (LDL-C) levels using statins is associated with significant reductions in cardiovascular (CV) events in a wide range of patient populations. Although statins are generally considered to be safe, recent studies suggest they are associated with an increased risk of developing Type 2 diabetes (T2D). This led the US Food and Drug Administration (FDA) to change their labelling requirements for statins to include a warning about the possibility of increased blood sugar and HbA1c levels and the European Medicines Agency (EMA) to issue guidance on a small increased risk of T2D with the statin class. This review examines the evidence leading to these clai…
Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex
2016
This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph) with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively). Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P < 0.001) although with impo…
Electrophysiological investigations on the central innervation of the rat and guinea-pig pineal gland
1984
The possible influence of central nervous structures on the electrical activity of single pineal cells was investigated in rat and guinea-pig. In the rat electrical stimulation of the hippocampal formation elicited both single cell responses with different latencies and mostly long-term excitations in single pineal cells, while stimulation of the habenular nuclei caused clear orthodromical responses with different latencies, alterations in the rate of spontaneous electrical activity and evoked discharges of "silent" units. In the guinea-pig electrical stimulation of the paraventricular nucleus influenced predominantly cells in the deeper layers of the posterior part of the pineal gland. Ele…
Efficacy of a blended low-intensity internet-delivered psychological programme in patients with multimorbidity in primary care: study protocol for a …
2019
BackgroundThe World Health Organization (WHO) has included comorbidity between depression and a chronic disease among the 10 leading global health priorities. Although there is a high prevalence of multimorbidity, health care systems are mainly designed for the management of individual diseases. Given the difficulty in delivering face-to-face psychological treatments, alternative models of treatment delivery have been proposed, emphasizing the role of technologies such as the Internet. The aim of this study is to assess the efficacy in Primary Care (PC) of a blended low-intensity psychological intervention applied using information and communication technologies (ICTs) for the treatment of …
Treatment of pituitary resistance to thyroid hormone (PRTH) in an 8-year-old boy.
1996
We report on an 8-year-old boy with pituitary resistance to thyroid hormone (PRTH) having a cysteine for arginine substitution at codon 320 in the TR-beta gene who was presented because of thyrotoxicosis. Due to its suppressive effect on the pituitary thyrotropin secretion, treatment with D-thyroxine (D-T4) was started. After a few days, clinical euthyroidism was achieved but thyroid stimulating hormone secretion was not suppressed. Symptoms of thyrotoxicosis relapsed when therapy was interrupted so that therapy with D-T4 was reinstituted and continued to date. Symptoms did not recur, and the psychomotor development proceeded normally. D-T4 should therefore be considered in the treatment of…
Resistance to thyroid hormone in a family caused by a new point mutation L330S in the thyroid receptor (TR) beta gene.
1997
Resistance to thyroid hormone (RTH) is an inherited defect manifesting as variable tissue hyporesponsiveness to thyroid hormone, usually caused by mutations in the thyroid hormone receptor beta (TR beta) gene. Up to now 78 mutations in this gene have been identified, mostly clustered in two regions located in exon 9 and 10. We describe a new point mutation replacing the normal thymidine-1274 with a cytosine that results in the substitution of the normal leucine-330 with a serine (L330S) in the receptor protein. This mutation was identified in an 11-year-old boy who presented with symptoms and signs suggestive of both hyperthyroidism and hypothyroidism. Interestingly a mutation in the same c…
Effect of Thyroid Hormones on Urea Biosynthesis and Related Processes in Rat Liver*
1988
The results of the few studies on the effect of the thyroid status on nitrogen metabolism have been inconclusive and/or contradictory. In an attempt to elucidate this important relationship, we have studied the effect of experimental hypo- and hyperthyroidism on urea biosynthesis and related processes. We have found that the capacity of the liver to synthesize urea was increased in hypothyroid rats, as were the activities of the urea cycle enzymes; there were also changes in the activities of some related enzymes and in the levels of intermediates and amino acids. Isolated hepatocytes from these rats showed an increased capacity for urea synthesis. In hyperthyroid rats the picture was more …