Dopaminergic regulation of crustacean hyperglycemic hormone and glucose levels in the hemolymph of the crayfish Procambarus clarkii.
The effects of dopamine on crustacean hyperglycemic hormone (CHH) release and hemolymph glucose levels in the crayfish Procambarus clarkii were investigated. A quantitative sandwich enzyme-linked immunosorbent assay (ELISA) using antibodies specific for Prc CHH was developed and characterized. The sensitivity of the ELISA was about 1 fmol/well. Specific measurement of CHH in hemolymph samples by the ELISA was demonstrated by the parallelism between CHH standard curve and sample (hemolymph) titration curve. Moreover, thermally stressed P. clarkii exhibited a characteristic change of hemolymph CHH levels as revealed by the ELISA. CHH and glucose levels increased significantly within 30 min of dopamine injection, peaked at 1 h, and returned to the basal levels at 4 h. Dose-dependent effects of dopamine on CHH and glucose levels were observed between 10(-8) to 10(-6) mol/animal. Dopamine-induced increases in CHH and glucose levels were absent in eyestalk-ablated animals. Finally, dopamine significantly stimulated the release of CHH from in vitro incubated eyestalk ganglia. These results suggest that dopamine enhances release of CHH into hemolymph that in turn evokes hyperglycemic responses and that the predominant site of dopamine-induced CHH release is the X-organ-sinus gland complex located within the eyestalk.
Zou
Hong-Shin
HS
Department of Biology, National Changhua University of Education, Changhua, Taiwan 50058, Republic of China.
Juan
Chi-Chih
CC
Chen
Shyh-Chi
SC
Wang
Hsin-Yuan
HY
Lee
Chi-Ying
CY
D000818:Animals; D060829:Arthropod Proteins; D003400:Astacoidea / Q000502:physiology*; D001786:Blood Glucose / Q000032:analysis*; D004298:Dopamine / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D017952:Ganglia, Invertebrate / Q000502:physiology; D006458:Hemolymph / Q000502:physiology; D066298:In Vitro Techniques; D007447:Invertebrate Hormones / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000097:blood*
D060829:Arthropod Proteins; D001786:Blood Glucose; D007447:Invertebrate Hormones; D009419:Nerve Tissue Proteins; C015947:hyperglycemic hormone, crustacean; D004298:Dopamine