Showing papers in "General and Comparative Endocrinology in 2010"

TL;DR: In this article, the effects of progestin, androgens, and estrogens on global testicular gene expression patterns (microarray analysis), and molecular mechanisms by which steroids regulate specific candidate genes (identified by subtractive hybridization approaches) during early stages of testis maturation are discussed.

TL;DR: Recent advances on teleost fish oocyte differentiation, maturation and ovulation are highlighted, including those involved in the degeneration and reabsorption of ovarian follicles (atresia).

TL;DR: Although precise information as to the physiological effects of KiSS1 in fish, notably on GnRH neurons and gonadotropin release, is still limited, KiSS neurons may emerge as the "gatekeeper" of puberty and reproduction in fish as in mammals.

TL;DR: The molecular and cellular characteristics of fish gametes are presented with a special interest for the mechanisms that could participate in the regulation ofgamete quality and an overview of the main factors that can impact gamete quality in teleosts is provided.

TL;DR: A broader hypothesis is extended that would place estrogens and Cyp19a1a in a pivotal position to control not only ovarian, but also testicular differentiation, in both gonochoristic and hermaphrodite fish species.

TL;DR: Puberty comprises the transition from an immature juvenile to a mature adult state of the reproductive system, i.e. the individual becomes capable of reproducing sexually for the first time, which implies functional competence of the brain-pituitary-gonad (BPG) axis.

TL;DR: Control of reproductive function in captivity is essential for the sustainability of commercial aquaculture production, and in many fishes it can be achieved by manipulating photoperiod, water temperature or spawning substrate, but a common question in regards to hormonal therapies is their effect on gamete quality.

TL;DR: Recombinant fish GtHs were produced for carp, seabream, channel and African catfish, goldfish, eel, tilapia, zebrafish, Manchurian trout and Orange-spotted grouper, where FSHR expression in Leydig cells explains the strong steroidogenic activity of FSH in certain fish species.

TL;DR: A brief review of the current understanding of the IGF signaling system is provided and recent findings on how local oxygen availability and IGFBPs act to specify IGF actions in muscle cells are discussed.

TL;DR: This paper is a review of the effects of stress on reproduction in fishes and the concept of hormesis is a useful way to think about the effect of stressors on fish reproduction since responses can be nonmonotonal, often biphasic.

TL;DR: How manipulation of the photic cues impact on fish circannual clock and annual cycle of reproduction, and how this can be used for aquaculture purposes is discussed.

TL;DR: Some of the predicted hormones similar to Drosophila and vertebrate insulins, bursicon, the putative proctolin homolog PKYMDT and allatostatin C shows that despite significant differences the molluscan and arthropod neuropeptidomes are more similar than generally recognized.

TL;DR: Results of field and laboratory observations suggest that some teleosts possess a sexually bipotential brain which can regulate two types of behaviors unlike most other vertebrates which have a discrete sex differentiation of their brain and can only perform gender-typical sexual behavior.

TL;DR: The regulatory roles of CHH and MIH at the levels of specific functions, temporal and spatial expression, titers, their binding sites on the target tissues, and second messengers from two crab species are reviewed.

TL;DR: It is supported that sLepA1 is involved in signaling the energy status in fat-depositing tissues in line with the mammalian model, whereas sL LepA2 may possibly play important roles in the digestive tract and liver.

TL;DR: Changes in FCM concentrations in autumn and winter over two years reliably tracked changes in plasma free cortisol levels obtained from the hormonal challenge test, indicating that both fecal and plasma measures of an animal's stress physiology are concordant.

TL;DR: Results suggest that thyroid hormone can be accurately and reliably measured in feces, providing important indices for environmental physiology across a diverse array of birds and mammals.

TL;DR: The results taken together suggest that kisspeptin via Kiss1r activation can act directly at the pituitary level to trigger LH, PRL, and GH secretion and gene expression in goldfish.

TL;DR: The utility of fecal hormone metabolite assays to document patterns of glucocorticoid levels in free-ranging animals is demonstrated, and patterns in stress hormone levels and reproductive condition in natural populations are rarely investigated.

TL;DR: For the first time, an endometriosis-like phenotype is described in mice, elicited by pre-natal exposition to BPA, which may induce to thoroughly reconsider the pathogenesis and treatment of endometRIosis, considering the high incidence of endometricriosis and the problems caused by associated infertility.

TL;DR: The results suggest that leptin has an acute effect on the regulation of food intake, energy expenditure and lipid metabolism in grass carp, but the effect can be rapidly counteracted through mechanisms that are currently unknown.

TL;DR: The seasonal changes in ghrelin and leptin support a role of these hormones in the long-term regulation of energy homeostasis in the anadromous Arctic charr and cannot be excluded, however, that the increase in liver leptin expression during autumn is related to sexual maturation.

TL;DR: How a better understanding of appetite-related hormones in fish might lead to the development of sustainable aquaculture is described and how the regulation of feeding in fish is still limited is described.

TL;DR: The present results indicate that the Kiss2/Kiss1r system most probably plays an important role in the regulation of reproductive function in the spawning period of grass puffer, possibly through the stimulation of GnRH1 secretion.

TL;DR: The results suggest the possible involvement of two Kiss genes in the brain and Kiss1 in the gonads of chub mackerel during seasonal gonadal development.

TL;DR: The results suggest that OVX-induced weight gain is mediated by hyperphagia and reduced locomotor activity in rats, but that in mice, it is primarily mediated by reduced locom motor activity and metabolic rate.

TL;DR: The findings support that the synergistic actions of TH and CS in metamorphosis occur at the level of expression of genes for TRbeta and D2, enhancing tissue sensitivity to TH.

TL;DR: Zebrafish leptin receptor message (lepr) was detected in all embryonic and larval stages examined, and in adult zebrafish and results showed that lepr expression was both spatially and temporally regulated.

TL;DR: Results indicate that GH/IGF axis, particularly muscle expression of GH-R, SL-R and IGF-I and -II, is sensitive to nutritional status in the tilapia.

TL;DR: Results indicate the GnIH/GnIHR system is expressed in the testis of house sparrows and its function is to reduce gonadotropin-stimulated testosterone production.