Project Title: Tissue and Plasma Enzyme Activities in Loggerhead Sea Turtles (Caretta caretta)
Project Manager: Eric Anderson
Organization: Mote Marine Laboratory (Non-Profit Organization)
Grant Amount: $3,520.00
Completion Date: 2008-10-01
Summary: In human and animal medicine blood chemistry profiles are routinely run for diagnostic and health monitoring purposes; however, there are species such as the loggerhead sea turtle (Caretta caretta) that the meaning of these basic parameters are unknown. This project is aimed to identify activities of six biochemically important enzymes in 28 body tissues of the loggerhead sea turtle. Samples will be taken from five loggerhead sea turtles that strand and are brought to Mote Marine Laboratory for rehabilitation, and subsequently die and are necropsied. A total of 27 tissue samples plus plasma from each turtle will be analyzed for six enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), and creatine kinase (CK). Tissue samples will be taken, homogenized, sonicated, and centrifuged to produce tissue supernatants that can be evaluated for these six enzymes activities. Knowledge of which tissues contribute to increases in these biochemical values will allow clinicians to make quicker and sounder decisions on proper treatment regimens. The results of this study will greatly increase the usefulness of a serum/plasma biochemical profile in regards to diagnosis and health assessment for sea turtles that are in rehabilitation as well as those maintained in captivity.
Results: This study is aimed to identify the concentration for these eight enzymes in the loggerhead sea turtle and to compare those tissue concentrations to plasma concentrations. Tissue samples were obtained from six sub-adult to adult loggerhead (Caretta caretta) and one Kemp's ridley (Lepidochelys Kempii) that stranded, were brought to Mote Marine Laboratory and Aquarium's Sea Turtle Rehabilitation Hospital (STRH), in Sarasota, FL, and subsequently die or were euthanized. Blood samples were obtained prior to death by venipuncture of the dorsal cervical sinus and placed in lithium heparin separator tubes (Vacutainer®). The samples were centrifuged at 2300 (+8%, -5%) rpm for five minutes, and 1-1.8 ml aliquots of the plasma were frozen at –80 °C until submission for analysis. A necropsy with histopathologic review of major tissues was performed on all of the sea turtles. In addition to the plasma sample, tissue samples of at least 0.5 gram were collected from skin, fat, skeletal muscle (pectoralis & rectus), cardiac muscle (atrium & ventricle), aorta, large vein, trachea, lung, esophagus, stomach, duodenum, mid small intestines, distal small intestines, large intestines, pancreas, liver, gall bladder, spleen, kidney, urinary bladder, gonads, bone (ulna), thyroid, adrenal gland, thymus, brain, and spinal cord. All tissue samples were placed in whirl packs and stored at –80 °C until they were processed. The significant findings that we have identified are as follows: 1) AST, AP, LDH and CK appear to be found in almost all of the tissues evaluated, and therefore less valuable diagnostically. 2) GGT, ALT and AST were the highest enzymes in the kidney and liver, with GGT appearing to be the best enzyme to evaluate these organs. 3) Amylase and lipase are unique to the pancreas as seen in other animals. These appear to be the most important findings. All of the turtles evaluated in this study were sick and subsequently died or were euthanized during rehabilitation. The values and patterns of enzyme distribution among the body tissues may thus be slightly different in healthy sea turtles. It is also necessary to recognize that when evaluating tissue enzyme activity levels the tissue processing and analytical techniques used may have affects on the actual determined values. Due to this situation, qualitative patterns of enzyme activities are more important to evaluate then actual quantitative values. (Author: Eric T. Anderson, D.V.M.)