Pigment-dispersing hormone immunoreactive neurons in the blowfly nervous system.

ABSTRACT

We could demonstrate pigment-dispersing hormone immunoreactive (PDHIR) neurons in the brain and ventral ganglia of the blowfly Phormia terraenovae. PDHIR neurons were found in the optic lobe. Their processes supply the lamina, medulla and lobula complex bilaterally. Large PDHIR cell bodies in the protocerebrum have processes in the proto- and tritocerebrum and axons to the aorta wall and foregut. Eight pairs of PDHIR neurons are found dorsally and three pairs ventrally in the fused abdominal neuromeres; one pair is located ventrally in each of the thoracic neuromeres. The ventral abdominal PDHIR neurons are efferents that innervate the hindgut. PDHIR neurons may play different functional roles as neurohormones or neuromodulators in different parts of the nervous system and its peripheral targets.