Cardiorespiratory action of opioid/tachykinin agonist peptide hybrid in anaesthetized rats: Transduction pathways.

AWL3106 composed of opioid (dermorphin) and tachykinin (substance P) pharmacophores is a new compound with high analgesic potency and markedly reduced ability to induce tolerance and dependence. The present study aimed to determine the respiratory and cardiovascular responses evoked by this peptide in urethane-chloralose anaesthetized, spontaneously breathing rats in the presence or absence of vagal connection. Intravenous injection of AWL3106 at a dose of 0.

Cardiorespiratory activity of C-terminal pentapeptide of substance P in anaesthetized rats.

Experiments were performed in anaesthetized, spontaneously breathing rats to: (1) analyse the respiratory and cardiovascular effects of C-terminal fragment of substance P (AWL2077) as referred to those exerted by the parent undecapeptide, (2) determine the involvement of lung vagal afferents to these responses. Each peptide was injected intravenously at a dose of 0.3μmol/kg into neurally intact or midcervically vagotomized rats.