Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar
Abstract One of the most clearly defined endocrine changes during the parr-smolt transformation of anadromous salmonids is an increase in plasma levels of thyroid hormones. The role of pineal hormone melatonin in timing and synchronisation of smoltification is widely discussed. The effect of adminis...
Main Authors: | , , , , |
---|---|
Other Authors: | |
Format: | Text |
Language: | English |
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1049.9796 http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf |
id |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.1049.9796 |
---|---|
record_format |
openpolar |
spelling |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.1049.9796 2023-05-15T15:31:08+02:00 Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar Ewa Kulczykowska Ewa Sokolowska Børge Takvam Sigurd Stefansson Lars Ebbesson The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1049.9796 http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1049.9796 http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf text ftciteseerx 2020-04-05T00:26:07Z Abstract One of the most clearly defined endocrine changes during the parr-smolt transformation of anadromous salmonids is an increase in plasma levels of thyroid hormones. The role of pineal hormone melatonin in timing and synchronisation of smoltification is widely discussed. The effect of administration of exogenous thyroxine (T4) on plasma melatonin was investigated in juvenile Atlantic salmon (Salmo salar) at the early stages of parr-smolt transformation. Fish were kept in fresh water under simulated-natural photoperiod and exposed to exogenous T4. Fish were sampled at 12.00 and 24.00 h from treatment and control tanks, 2 and 14 days after treatment started. Plasma melatonin and L-thyroxine were measured using RIA and competitive enzyme immunoassay, respectively. After 2 days of T4 treatment, marked difference in plasma melatonin concentration measured at 12.00 and 24.00 h was still observed in both groups. However, 2-week exposure to T4 caused a reduction in night-time plasma melatonin level and thus, probably, inhibited melatonin related time-keeping system in juvenile salmon. Additional studies are needed to clarify the mechanism of the described phenomenon. ᮊ Text Atlantic salmon Salmo salar Unknown |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
ftciteseerx |
language |
English |
description |
Abstract One of the most clearly defined endocrine changes during the parr-smolt transformation of anadromous salmonids is an increase in plasma levels of thyroid hormones. The role of pineal hormone melatonin in timing and synchronisation of smoltification is widely discussed. The effect of administration of exogenous thyroxine (T4) on plasma melatonin was investigated in juvenile Atlantic salmon (Salmo salar) at the early stages of parr-smolt transformation. Fish were kept in fresh water under simulated-natural photoperiod and exposed to exogenous T4. Fish were sampled at 12.00 and 24.00 h from treatment and control tanks, 2 and 14 days after treatment started. Plasma melatonin and L-thyroxine were measured using RIA and competitive enzyme immunoassay, respectively. After 2 days of T4 treatment, marked difference in plasma melatonin concentration measured at 12.00 and 24.00 h was still observed in both groups. However, 2-week exposure to T4 caused a reduction in night-time plasma melatonin level and thus, probably, inhibited melatonin related time-keeping system in juvenile salmon. Additional studies are needed to clarify the mechanism of the described phenomenon. ᮊ |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Ewa Kulczykowska Ewa Sokolowska Børge Takvam Sigurd Stefansson Lars Ebbesson |
spellingShingle |
Ewa Kulczykowska Ewa Sokolowska Børge Takvam Sigurd Stefansson Lars Ebbesson Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar |
author_facet |
Ewa Kulczykowska Ewa Sokolowska Børge Takvam Sigurd Stefansson Lars Ebbesson |
author_sort |
Ewa Kulczykowska |
title |
Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar |
title_short |
Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar |
title_full |
Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar |
title_fullStr |
Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar |
title_full_unstemmed |
Influence of exogenous thyroxine on plasma melatonin in juvenile Atlantic salmon (Salmo salar |
title_sort |
influence of exogenous thyroxine on plasma melatonin in juvenile atlantic salmon (salmo salar |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1049.9796 http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_source |
http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1049.9796 http://www.iopan.gda.pl/PhyMO/pdfs/CBPB2004T4.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766361636193435648 |