Quantification by radioimmunoassay of adipokinetic hormone-I in neural tissues in the head of Locusta migratoria

1. 1. Using a [3H]AKH-I probe, a radioimmunoassay has been developed which is specific for adipokinetic hormone-I (AKH-I). 2. 2. Age-related changes occur in the AKH-I content of male and female corpora cardiaca: levels are ca 200 pmol per pair of glands at emergence, increasing to ca 800 pmol by day 30, but the patterns of increase are complex and differ temporally between the sexes. 3. 3. No age-related changes are found in the amounts of AKH-I in brains from males or females, with total amounts < 20pmol/brain. 4. 4. No relationship was found between oocyte length and the AKH-I content of female corpora cardiaca. 5. 5. Reverse phase HPLC confirms that the immunoreactive material in extracts of male and female brains has the same retention time as AKH-I. 6. 6. AKH-I was not detected in suboesophageal ganglia.