title: Salt gland blood flow in the hatchling green turtle, Chelonia mydas.
abstract: Microsphere and morphometric techniques were used to investigate any circulatory changes that accompany secretion by the salt glands of hatchling Chelonia mydas. Salt glands were activated by a salt load of 27.0 mmol NaCl x kg body mass (BM)(-1), resulting in a mean sodium secretion rate of 4.14 +/- 0.11 mmol Na x kg BM(-1) x h(-1) for a single gland. Microsphere entrapment was approximately 160-180 times greater in the active salt gland than the inactive gland, inferring a similar change in blood flow through salt gland capillaries. The concentration of microspheres trapped in the salt gland was significantly correlated with the rate of tear production (ml x kg BM(-1) x h(-1)) and the total rate of sodium secretion (mmol Na x kg BM(-1) x h(-1)) but not with tear sodium concentration (mmol Na x l(-1)). Adrenaline (500 microg x kg BM(-1)) inhibited tear production within 2 min and reduced microsphere entrapment by approximately 95% compared with active glands. The volume of filled blood vessels increased from 0.03 +/- 0.01% of secretory lobe volume in inactive salt gland sections to 0.70 +/- 0.11% in active gland sections. The results demonstrate that capillary blood flow in the salt gland of C. mydas can regulate the activity of the gland as a whole.
authors.affiliation: School of Environmental Science, Engineering and Policy, Drexel University, Philadelphia, PA 19104, USA. richard.reina@drexel.edu
authors.forename: R
authors.initials: R
authors.lastname: Reina
mesh_terms: D000818:Animals; D002196:Capillaries / Q000502:physiology; D004837:Epinephrine / Q000494:pharmacology; D008863:Microspheres; D012039:Regional Blood Flow; D012491:Salt Gland / Q000098:blood supply* / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000008:administration & dosage; D013666:Tears / Q000378:metabolism; D014426:Turtles / Q000033:anatomy & histology / Q000502:physiology*
chemical_list: D012965:Sodium Chloride; D012964:Sodium; D004837:Epinephrine