| 1. |
- Duan, R D, et al.
(author)
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Stimulatory effects of human pancreatic polypeptide on rat pancreatic acini
- 1985
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In: Regulatory Peptides. - 0167-0115. ; 12:3, s. 215-222
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Journal article (peer-reviewed)abstract
- The effect of human pancreatic polypeptide (HPP) on rat pancreatic acini has been studied. It was found that HPP stimulated amylase and lipase release from the acini. The secretory response of acini to HPP was dose-dependent in a sigmoidal fashion. Between 10(-9) M and 10(-8) M concentration of HPP there was a slow increase of enzyme release to about 40-60% over basal release. At concentrations of HPP above 10(-8) M there was a rapid increase of enzyme release, amounting to 4-6 times over basal release at 10(-6) M concentration of HPP. The potency of HPP compared to other secretagogues at 10(-7) M concentration was 45% of CCK, 60% of carbachol and 75% of secretin. HPP did not inhibit the effect of CCK, secretin and carbachol on amylase release. The amylase release stimulated by HPP was accompanied by an increase in 45Ca2+ efflux. Atropine or dibutyryl cyclic GMP did not influence the effect of HPP. It is concluded that HPP stimulates the release of enzymes from rat pancreatic acini and that Ca2+ may be a mediator for this secretion.
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| 2. |
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| 3. |
- Grundemar, L, et al.
(author)
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Neuropeptide Y : prejunctional inhibition of vagally induced contractions in the guinea pig trachea
- 1988
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In: Regulatory Peptides. - : Elsevier BV. - 0167-0115. ; 23:3, s. 309-313
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Journal article (peer-reviewed)abstract
- The effects of neuropeptide Y (NPY) on the contractile response to vagus nerve stimulation at different frequencies was studied in an isolated tracheal tube preparation from guinea pig. NPY had no effect on basal smooth muscle tension or on the contractile effect of carbachol, but inhibited vagally induced contractions in a concentration-dependent manner with a greater inhibition at low frequencies than at high. We suggest that the effect is exerted prejunctionally.
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| 4. |
- Hellstrand, Per, et al.
(author)
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Role of vasoactive intestinal polypeptide (VIP) in the neurogenic vasodilatation of the portal vein in the rabbit
- 1985
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In: Regulatory Peptides. - : Elsevier BV. - 1873-1686 .- 0167-0115. ; 12:4, s. 309-316
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Journal article (peer-reviewed)abstract
- A coarse network of nerve fibres displaying immunoreactivity for vasoactive intestinal polypeptide (VIP) was found in the wall of the hepatic portal vein of the rabbit. Electrical field stimulation of the rabbit portal vein in vitro, in the presence of adrenergic and cholinergic blockade, caused a marked relaxation of the vessel and a release of VIP into the perfusate. Addition of VIP to the tissue bath elicited a concentration-dependent inhibition of the mechanical activity of the portal vein. The results suggest that VIP containing neurones might participate in the non-cholinergic, non-adrenergic vasodilatation of the portal vein in the rabbit.
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| 5. |
- Stjernquist, Martin, et al.
(author)
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Immunocytochemical localization of galanin in the rat male and female genital tracts and motor effects in vitro
- 1988
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In: Regulatory Peptides. - : Elsevier BV. - 1873-1686 .- 0167-0115. ; 20:4, s. 335-343
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Journal article (peer-reviewed)abstract
- Galanin, a recently discovered neuropeptide, was studied in the rat male and female reproductive tracts by immunocytochemistry and in vitro pharmacology. Nerve fibers containing galanin immunoreactivity were most abundant in the female paracervical tissue, where they surrounded non-immunoreactive ganglion cells. Galanin nerves were also found in the uterus and Fallopian tubes, as well as in the vas deferens. When tested in vitro galanin contracted the smooth muscle of both the uterine horn and cervix. Galanin also slightly potentiated the response to electrical field stimulation in preparations from the uterine cervix and vas deferens, but it had no effect on the seminal vesicle. Galanin-(1-10), an N-terminal residue of galanin, also contracted the uterine horn, though higher concentrations were required. The neurally induced contractions were not influenced by galanin-(1-10) in any of the smooth muscle preparations tested. The muscle receptors mediating the direct contractile effects in the uterine horn seem to require the N-terminus of galanin, while the neuromodulatory effects on the electrically induced contractile activity seem to need the C-terminal part or the whole galanin molecule. Galanin may thus function as a neuromediator in the rat male and female genital organs.
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