Platelet-activating factor production occurs through stimulation of cholinergic and dopaminergic receptors in the chick retina

In previous work we showed that platelet-activating factor (PAF) was produced upon stimulation of the chick retina with acetylcholine (ACh) and dopamine (DA), via a dithiothreitol-insensitive cholinephosphotransferase (DTT-CPT). Other neurotransmitters were ineffective. Since ACh and DA stimulated PAF production at different stages of development, we advanced the hypothesis that selected cholinergic and dopaminergic receptors were involved. In this paper we demonstrate that only muscarinic or D₂ (and not D₁ and nicotinic) receptor stimulation induced PAF production in the chick retina either before or after hatching. Moreover, our data show that PAF production was completely prevented by blockage of these receptors by specific antagonists. These data further substantiate the hypothesis that PAF synthesis could be physiologically associated with synapse stimulation.