Presence of thyroxine in eggs and changes in its content during early development of chum salmon, Oncorhynchus keta

Tagawa, Masatomo; Hirano, Tetsuya

doi:10.1016/0016-6480(87)90068-2

Cited by 156 publications

(84 citation statements)

References 20 publications

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“…The reason for the difference between the two studies may be a consequence of the careful collection of individual samples instead of pools, use of a validated staging scheme (Saele et al, 2004) and the introduction of a heat treatment step prior to RIA of samples. Although previous studies of THs during ontogeny of salmonids (de Jesus and Hirano, 1992;Tagawa and Hirano, 1987;Leatherland et al, 1989), striped bass (Morone saxatilis) and conger eel (Brown et al, 1987;Yamano et al, 1991b) have not reported problems of interassay variability of T 3 in the same samples or between different samples, this was found to be a difficulty with the Atlantic halibut larval extracts. The use of a heat treatment is an indispensable step in sample preparation for the analysis of THs in human plasma samples (Neeley and Alexander, 1983) in order to overcome the "matrix" effect caused by complexity of biological samples (Selby, 1999).…”

Section: Whole Body Th Levels In Metamorphosing Larvaementioning

confidence: 87%

Thyroid hormone receptor expression during metamorphosis of Atlantic halibut (Hippoglossus hippoglossus)

Galay-Burgos

Power

Llewellyn

et al. 2008

Molecular and Cellular Endocrinology

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Flatfish such as the Atlantic halibut (Hippoglossus hippoglossus) undergo a dramatic metamorphosis that transforms the pelagic, symmetric larva into a benthic, cranially asymmetric juvenile. In common with amphibian metamorphosis, flatfish metamorphosis is under endocrine control with thyroid hormones being particularly important. In this report we confirm that tri-iodothyronine (T 3 ) levels peak at metamorphic climax during halibut metamorphosis. Moreover we have isolated cDNA clones of TR and TR genes and confirmed the presence in halibut of two TR isoforms (representing the products of distinct genes) and two TR isoforms (generated from a single gene by alternative splicing). Real time PCR was used to assess expression of these genes during metamorphosis. TR shows the most dramatic expression profile, with a peak occurring during metamorphic climax.

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Section: Whole Body Th Levels In Metamorphosing Larvaementioning

confidence: 87%

Thyroid hormone receptor expression during metamorphosis of Atlantic halibut (Hippoglossus hippoglossus)

Galay-Burgos

Power

Llewellyn

et al. 2008

Molecular and Cellular Endocrinology

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“…The importance of the thyroid hormones (THs), thyroxine (T 4 ) and triiodothyronine (T 3 ), in vertebrate development is well established (Hadley 1992;Tata et al 1993;Power et al 2001). In fish, prior to the maturation of the larval thyroid gland, fish eggs and, subsequently, the larval yolk sack contain significant amounts of THs of maternal origin (Kobuke et al 1987;Tagawa and Hirano 1987;Brown et al 1988;Greenblatt et al 1989;Tagawa et al 1990a, b). This source of THs is likely to be of importance for the physiological regulation of growth, development and osmoregulation in larvae prior to the development of functional endogenous thyroid follicles.…”

Section: Introductionmentioning

confidence: 99%

Thyroid and pituitary gland development from hatching through metamorphosis of a teleost flatfish, the Atlantic halibut

et al. 2005

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Fish larval development, not least the spectacular process of flatfish metamorphosis, appears to be under complex endocrine control, many aspects of which are still not fully elucidated. In order to obtain data on the functional development of two major endocrine glands, the pituitary and the thyroid, during flatfish metamorphosis, histology, immunohistochemistry and in situ hybridization techniques were applied on larvae of the Atlantic halibut (Hippoglossus hippoglossus), a large, marine flatfish species, from hatching through metamorphosis. The material was obtained from a commercial hatchery. Larval age is defined as day-degrees (D°=accumulated daily temperature from hatching). Sporadic thyroid follicles are first detected in larvae at 142 D°(27 days post-hatch), prior to the completion of yolk sack absorption. Both the number and activity of the follicles increase markedly after yolk sack absorption and continue to do so during subsequent development. The larval triiodothyronine (T 3 ) and thyroxine (T 4 ) content increases, subsequent to yolk absorption, and coincides with the proliferation of thyroid follicles. A second increase of both T 3 and T 4 occurs around the start of metamorphosis and the T 3 content further increases at the metamorphic climax. Overall, the T 3 content is lower than T 4 . The pituitary gland can first be distinguished as a separate organ at the yolk sack stage. During subsequent development, the gland becomes more elongated and differentiates into neurohypophysis (NH), pars distalis (PD) and pars intermedia (PI). The first sporadic endocrine pituitary cells are observed at the yolk sack stage, somatotrophs (growth hormone producing cells) and somatolactotrophs (somatolactin producing cells) are first observed at 121 D°( 23 days post-hatch), and lactotrophs (prolactin producing cells) at 134 D°(25 days post-hatch). Scarce thyrotrophs are evident after detection of the first thyroid follicles (142 D°), but coincident with a phase in which follicle number and activity increase (260 D°). The somatotrophs are clustered in the medium ventral region of the PD, lactotrophs in the anterior part of the PD and somatolactotrophs are scattered in the mid and posterior region of the pituitary. At around 600 D°, coinciding with the start of metamorphosis, somatolactotrophs are restricted to the interdigitating tissue of the NH. During larval development, the pituitary endocrine cells become more numerous. The present data on thyroid development support the notion that thyroid hormones may play a significant role in Atlantic halibut metamorphosis. The time of appearance and the subsequent proliferation of pituitary somatotrophs, lactotrophs, somatolactotrophs and thyrotrophs indicate at which stages of larval development and metamorphosis these endocrine cells may start to play active regulatory roles.

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“…After 10 weeks, three animals per tank (nine per treatment) were randomly sampled and killed with a sharp blow in the head. T3 and T4 levels (ng ml -1 ) were determined according to Tagawa and Hirano (1987), and Perez- Dominguex and Holt (2006).…”

Section: Methodsmentioning

confidence: 99%

“…Afterward, chloroform (200 ll), methanol (50 ll), and barbital buffer (50 ll; 0.1 M, pH = 8.6) were added to the remaining dried extract in the tubes shaken horizontally for 10 min. The supernatants containing thyroid hormones were transferred to clean tubes and dried at 45°C for 4 h. The dried extracts were dissolved by barbital buffer (1 ml) containing 0.1 % gelatin and kept at -70°C until use (Tagawa and Hirano 1987;Perez-Dominguez and Holt 2006).…”

Section: Methodsmentioning

confidence: 99%

Growth performance and thyroid hormones of Caspian kutum, Rutilus frissi, juveniles in response to dietary carbohydrate levels

et al. 2014

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The aim of this study was to evaluate the effects of a practical diet containing different carbohydrate levels on growth rate, feed utilization, and thyroid hormones (T3 and T4) of Caspian kutum fingerlings. Fish with an initial average weight of 0.8 ± 0.2 g were fed five formulated isonitrogenous and isoenergetic diets with different carbohydrate levels of 15, 20, 25, 30 and 35 % in triplicate groups for 10 weeks. Based on the results, growth performance of Rutilus frissi was significantly affected by the dietary carbohydrate levels (P \ 0.05). Maximum weight gain, specific growth rate, and protein efficiency ratio was observed in the fish fed diet with 35 % carbohydrate. Results of thyroid hormones showed that T4 levels were not significantly different by different carbohydrate levels (P [ 0.05). The highest amount of T4 was observed in kutum juveniles fed with a carbohydrate level of 15 %. The levels of T4 were significantly affected by dietary carbohydrate levels (P \ 0.05) with the highest amount in kutum juveniles fed 15 % of carbohydrate. In conclusion, this study indicates that increasing carbohydrate levels from 15 to 35 %, with no negative effects on growth parameters in R. frissi juveniles, leads to an efficient protein ratio and optimal growth. Moreover, no clear correlation was found between fish growth and thyroid hormones.

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Presence of thyroxine in eggs and changes in its content during early development of chum salmon, Oncorhynchus keta

Cited by 156 publications

References 20 publications

Thyroid hormone receptor expression during metamorphosis of Atlantic halibut (Hippoglossus hippoglossus)

Thyroid hormone receptor expression during metamorphosis of Atlantic halibut (Hippoglossus hippoglossus)

Thyroid and pituitary gland development from hatching through metamorphosis of a teleost flatfish, the Atlantic halibut

Growth performance and thyroid hormones of Caspian kutum, Rutilus frissi, juveniles in response to dietary carbohydrate levels

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