Journal Article
Title | Parathyroid hormone-related protein: a calcium regulatory factor in sea bream (Sparus aurata L.) larvae. |
Publication Type | Journal Article |
Authors | Guerreiro, PM, Fuentes, J, Power, DM, Ingleton, PM, Flik, G, Canario, AVM |
Year of Publication | 2001 |
Journal | Am J Physiol Regul Integr Comp Physiol |
Volume | 281 |
Issue | 3 |
Date Published | 2001 Sep |
Pagination | R855-60 |
ISSN | 0363-6119 |
Keywords | Adaptation, Physiological, Animals, Calcium, Dose-Response Relationship, Drug, Drinking, Fresh Water, Ion Transport, Larva, Parathyroid Hormone-Related Protein, Peptide Fragments, Proteins, Sea Bream, Seawater |
Abstract | The effects of an N-terminal peptide (amino acids 1-38) of Fugu parathyroid hormone-related protein (PTHrP 1-38) on calcium regulation of larval sea bream were investigated in seawater (36 per thousand) and after transfer to dilute seawater (12 per thousand). Exposure to PTHrP 1-38 evoked a 1.5-fold increase in calcium influx in both full-strength and dilute seawater. Calcium influx in dilute seawater-adapted larvae was roughly one-half that observed in full-strength seawater controls. PTHrP 1-38 also reduced drinking of fish in seawater but, at all concentrations tested, was without effect in dilute seawater. The amount of water imbibed was 55% lower in dilute seawater than in seawater. PTHrP 1-38 exposure affected the calcium influx route: the main contribution of calcium uptake shifted from intestinal absorption to extraintestinal uptake, probably by the induction of a dose-dependent increase in branchial (active) transport. Moreover, seawater-adapted fish exposed to 1 nM and 10 mM PTHrP 1-38 experienced a 2.5-fold reduction in overall calcium efflux. Overall, the calciotropic action of PTHrP 1-38 resulted in a dose-dependent increase in net calcium balance. |
Sapientia | |
Alternate Journal | Am. J. Physiol. Regul. Integr. Comp. Physiol. |
PubMed ID | 11507001 |