Effects of tachykinins on inositol phospholipid hydrolysis in slices of hamster urinary bladder

Abstract

1Tachykinin-stimulated inositol phospholipid hydrolysis was examined in slices of hamster urinary bladder.2 In the presence of lithium, to inhibit inositol monophosphatase activity, substance P, eledoisin and related tachykinins induced large, dose-dependent increases in [3H]-inositol monophosphate accumulation. 3 The responses to substance P and eledoisin were not antagonized by the cholinoceptor antagonist, atropine. 4 The rank order of potency for various tachykinins was kassinin> neurokinin A> neurokinin B > eledoisin > physaelamin > substance P > substance P methyl ester. 5 The synthetic analogue [p-Glu6, D-Pro9] SP (6-11) was considerably more potent than its L-prolyl stereoisomer at stimulating inositol phospholipid hydrolysis. 6 These results suggest that in the hamster urinary bladder, tachykinin-induced inositol phospholipid breakdown is mediated via tachykinin receptors of the SP-E type, as opposed to the SP-P type.

Bradykinin B1 receptors in the rabbit urinary bladder: induction of responses, smooth muscle contraction, and phosphatidylinositol hydrolysis

“…The methodology was adapted from Berridge et al (1982) and Bristow et al (1987 Berridge et al (1982). Distilled water (0.30 ml) and chloroform (0.31 ml) were added, the samples centrifuged (1000 g for 5 min).…”

Non‐peptide antagonists, CP‐96,345 and RP 67580, distinguish species variants in tachykinin NK1 receptors

“…All three tachykinin receptor types stimulate phosphoinositide metabolism. NK1-stimulation of this pathway has been reported in guinea-pig ileum longitudinal smooth muscle (Watson & Downes, 1983); NK2-stimulation in the hamster urinary bladder (Bristow et al, 1987) and NK3 stimulation in myenteric plexus of guineapig ileum (Guard et al, 1988). Recently, Nakajima et al (1992) demonstrated that individual tachykinin receptors stably transfected in Chinese hamster ovary cells couple to phosphoinositide hydrolysis.…”

“…UCI1 and LRM55 cells have been shown to express NK, receptors (Johnson & Johnson, 1992;Perrone et al, 1986). In order to determine whether other tachykinin receptors are also present on LRM55 and UCIl cells we measured the ability of senktide, a selective NK3 agonist (Wormser et al, 1986), and [PAla8]NKA(4-10), a selective NK2 agonist (Rovero et al, 1989), to stimulate [3H]-inositol phosphate accumulation, as both of these receptor types have been shown to stimulate inositol phospholipid hydrolysis (Bristow et al, 1987;Guard et al, 1988).…”

Different tachykinin receptor subtypes are coupled to the phosphoinositide or cyclic AMP signal transduction pathways in rat submandibular cells

“…However, there is evidence that, depending on the tissue, all the receptor subtypes are capable of mediating PIP2 hydrolysis. Thus PIP2 hydrolysis has been observed in NK2-type tissues such as the rat ileum and hamster urinary bladder [14,15]. Substance P and related tachykinins also stimulate inositol phospholipid hydrolysis in guinea pig ileum longitudinal muscle-myenteric plexus preparations, an example of NK3-type tissue [16].…”