Peptidergic and nitrergic inhibitory neurotransmissions in the hamster jejunum: regulation of vasoactive intestinal peptide release by nitric oxide.
Regulation of vasoactive intestinal peptide (VIP) release by nitric oxide (NO) was investigated in the hamster jejunum. Electrical field stimulation and applied NO (3-100 microM) evoked biphasic hyperpolarizations consisting of an initial transient hyperpolarizing component followed by a second more slowly developing component (late component). The NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (200 microM) abolished the biphasic inhibitory junction potential evoked by electrical field stimulation. The NO scavenger oxyhemoglobin (50 microM) and the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ; 10 microM) abolished both components of the inhibitory junction potentials and the NO-induced hyperpolarizations. VIP(6-28) (1 microM), which abolished VIP (3 microM)-induced hyperpolarizations, also inhibited the late components of the inhibitory junction potentials and the NO-induced hyperpolarizations. ODQ inhibited VIP release and cAMP production by electrical field stimulation and NO application. N(6)-2,0-Dibutyryladenosine 3',5'-cyclic monophosphate (0.1-3 mM) caused a membrane hyperpolarization. These results suggest that NO may stimulate VIP release from enteric nerves in the hamster jejunum. In addition, we propose that NO and NO-stimulated VIP contribute to the early and late components of the inhibitory junction potentials, respectively, in the circular smooth muscle cells of the hamster jejunum.
Matsuyama
H
H
Department of Pathogenetic Veterinary Science, The United Graduate School, Gifu University, Yanagido 1-1, Gifu, Japan
Unno
T
T
El-Mahmoudy
A M
AM
Komori
S
S
Kobayashi
H
H
Thapaliya
S
S
Takewaki
T
T
D000818:Animals; D006224:Cricetinae; D000242:Cyclic AMP / Q000378:metabolism / Q000494:pharmacology; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D004558:Electric Stimulation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors / Q000378:metabolism; D007583:Jejunum / Q000294:innervation* / Q000378:metabolism; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008647:Mesocricetus; D009130:Muscle, Smooth / Q000294:innervation* / Q000378:metabolism; D009197:Myenteric Plexus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D026602:Nitrergic Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism* / Q000494:pharmacology; D010069:Oxadiazoles / Q000494:pharmacology; D010108:Oxyhemoglobins / Q000378:metabolism / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011688:Purinones / Q000494:pharmacology; D020889:Rolipram / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism* / Q000494:pharmacology
C116907:1H-(1,2,4)oxadiazolo(4,3-a)-quiloxalin-1-one; D004791:Enzyme Inhibitors; D010069:Oxadiazoles; D010108:Oxyhemoglobins; D010446:Peptide Fragments; D010726:Phosphodiesterase Inhibitors; D011688:Purinones; C113198:vasoactive intestinal peptide (6-28); C016276:8-bromocyclic GMP; D009569:Nitric Oxide; D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP; D006162:Guanylate Cyclase; C011145:zaprinast; D006152:Cyclic GMP; D020889:Rolipram; D019331:NG-Nitroarginine Methyl Ester