High-performance liquid chromatography (HLPC) measurement of catecholamines in single honeybee brains reveals caste-specific differences between worker bees and queens in apis mellifera

1. Catecholamines were determined by HPLC in honeybee brains using automatized extraction and on-line detection with an electrochemical detector.2. This method has high sensitivity in the range of fmols. Thus, catechols can be measured in single brains as well as in parts of brains.3. The comparison of brains of worker bees and queens shows a caste-specific content of eatecholamine concentrations in worker bees and queens.4. The amount of norepinephrine and dopamine are higher in queens than in worker bees.5. The differences are not caused by the different size of the respective brains, but reflect a difference in the two female castes.