“…In addition to the cockroach proctodeum [3,8,10,12], proctolin stimulates contractions of foregut of the locust S. gregaria [27,[29][30][31] and the midgut of the cockroach Diploptera punctata [32], and it is now regarded as the main neuromuscular transmitter/modulator in the gut of most insect species [8,10,12,15,32]. Further, it induces myogenic contractions of the extensor tibiae in Locusta [33], and the of coxal depressor in Periplaneta [34]; it stimulates oviduct contractility in Periplaneta [35], Leucophaea [8,36] and Locusta [37]; and it increases the rate of contraction of the hyperneural muscle in Periplaneta [38] and the dorsal longitudinal muscles of Teleogryllus oceanicus [39].…”