Cholinergic receptors of the central nervous system of insects

Isolation of putative acetylcholine receptor proteins from housefly brain

“…The data point to differences between the nicotinic ACh receptors of fish electric organs and the housefly brain putative ACh receptors. First is the apparent in vitro lower affinity of the latter for cholinergic drugs and ACh (Eldefrawi and O 'Brien, 1970;Aziz and Eldefrawi, 1973), unless we consider the hypothesis that the in vitro higher affinity binding of ACh and activators observed to electric organ ACh receptors is due to in vitro desensitization of these receptors (Weber et al, 1975). The lack of effect on [3H]decamethonium or [3H]nicotine binding to the housefly S2 fraction by a-BGT or the specific neurotoxin of N. naja siamensis venom (Table I), and the apparent absence of their direct binding of [125I]a-BGT (Figure 3), point to additional differences.…”