PMID- 18424682
OWN - NLM
STAT- MEDLINE
DCOM- 20080903
LR  - 20181201
IS  - 0022-0949 (Print)
IS  - 0022-0949 (Linking)
VI  - 211
IP  - Pt 9
DP  - 2008 May
TI  - Functional and morphological plasticity of crocodile (Crocodylus porosus) salt 
      glands.
PG  - 1482-9
LID - 10.1242/jeb.015636 [doi]
AB  - The estuarine crocodile, Crocodylus porosus, inhabits both freshwater and 
      hypersaline waterways and maintains ionic homeostasis by excreting excess sodium 
      and chloride ions via lingual salt glands. In the present study, we sought to 
      investigate the phenotypic plasticity, both morphological and functional, in the 
      lingual salt glands of the estuarine crocodile associated with chronic exposure 
      to freshwater (FW) and saltwater (SW) environments. Examination of haematological 
      parameters indicated that there were no long-term disruptions to ionic 
      homeostasis with prolonged exposure to SW. Maximal secretory rates from the salt 
      glands of SW-acclimated animals (100.8+/-14.7 micromol 100 g(-0.7) body mass 
      h(-1)) were almost three times greater than those of FW-acclimated animals 
      (31.6+/-6.2 micromol 100 g(-0.7) body mass h(-1)). There were no differences in 
      the mass-specific metabolic rate of salt gland tissue slices from FW- and 
      SW-acclimated animals (558.9+/-49.6 and 527.3+/-142.8 microl O(2) g(-1) h(-1), 
      respectively). Stimulation of the tissue slices from SW-acclimated animals by 
      methacholine resulted in a 33% increase in oxygen consumption rate. There was no 
      significant increase in the metabolic rate of tissues from FW-acclimated animals 
      in response to methacholine. Morphologically, the secretory cells from the salt 
      glands of SW-acclimated animals were larger than those of FW-acclimated animals. 
      In addition, there were significantly more mitochondria per unit volume in 
      secretory tissue from SW-acclimated animals. The results from this study 
      demonstrate that the salt glands of C. porosus are phenotypically plastic, both 
      morphologically and functionally and acclimate to changes in environmental 
      salinity.
FAU - Cramp, Rebecca L
AU  - Cramp RL
AD  - School of Integrative Biology, The University of Queensland, St Lucia, Brisbane, 
      4072 Australia.
FAU - Meyer, Edward A
AU  - Meyer EA
FAU - Sparks, Nicole
AU  - Sparks N
FAU - Franklin, Craig E
AU  - Franklin CE
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - J Exp Biol
JT  - The Journal of experimental biology
JID - 0243705
SB  - IM
MH  - Alligators and Crocodiles/anatomy & histology/*physiology
MH  - Animals
MH  - Body Weight
MH  - Energy Metabolism/*physiology
MH  - *Environment
MH  - Fresh Water
MH  - Microscopy, Electron, Transmission
MH  - Osmotic Pressure
MH  - Oxygen Consumption/physiology
MH  - Salt Gland/metabolism/*physiology/*ultrastructure
MH  - Seawater
EDAT- 2008/04/22 09:00
MHDA- 2008/09/04 09:00
CRDT- 2008/04/22 09:00
PHST- 2008/04/22 09:00 [pubmed]
PHST- 2008/09/04 09:00 [medline]
PHST- 2008/04/22 09:00 [entrez]
AID - 211/9/1482 [pii]
AID - 10.1242/jeb.015636 [doi]
PST - ppublish
SO  - J Exp Biol. 2008 May;211(Pt 9):1482-9. doi: 10.1242/jeb.015636.