The tachykinin NH2-senktide, a selective neurokinin B receptor agonist, is a very potent inhibitor of salt appetite in the rat.
The tachykinin peptide [Asp5.6, MePhe8]substance P(5-11) (NH2-senktide), a senktide analogue lacking the N-terminal succinyl group, is a selective and metabolically stable NK-3 receptor agonist. In the present study it potently inhibited salt appetite induced by sodium depletion in rats. Argo-neurokinin B, too, inhibited salt appetite, but was less potent than NH2-senktide. Neither peptide inhibited drinking behaviour induced by subcutaneous hypertonic NaCl. NH2-senktide slightly inhibited angiotensin-induced drinking, while Argo-neurokinin B was ineffective. On the other hand, eledoisin was a potent inhibitor in the 3 behavioural tests. Present results indicate that activation of NK-3 receptors is involved in the antinatriorexic action of tachykinins, and that different receptor subtypes might be involved in the different effects of tachykinins on the rat ingestive behaviour.
Massi
M
M
Institute of Pharmacology, University of Camerino, Italy.
Polidori
C
C
Gentili
L
L
Perfumi
M
M
de Caro
G
G
Maggi
C A
CA
D000818:Animals; D001066:Appetite / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D007276:Injections, Intraventricular; D008297:Male; D015287:Neurokinin B / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D018042:Receptors, Neurokinin-3; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000502:physiology*; D012965:Sodium Chloride; D013373:Substance P / Q000031:analogs & derivatives* / Q000494:pharmacology; D015320:Tachykinins / Q000494:pharmacology*
D010446:Peptide Fragments; D018042:Receptors, Neurokinin-3; D017981:Receptors, Neurotransmitter; D015320:Tachykinins; C057852:substance P (5-11), Asp(5,6)-MePhe(8)-; D013373:Substance P; D012965:Sodium Chloride; D015287:Neurokinin B