CRF microinjected into the dorsal vagal complex inhibits TRH analog- and kainic acid-stimulated gastric contractility in rats.
The effect of CRF microinjected into the dorsal vagal complex (DVC) on centrally-stimulated gastric contractility was investigated in fasted, urethane-anesthetized rats. Miniature strain gauge force transducers were acutely implanted on the corpus of the stomach and contractility was analyzed by computer. Microinjection of the stable thyrotropin-releasing hormone (TRH) analog, RX 77368, (26 pmol) into the DVC induced a 12.2-fold stimulation of gastric contractility within 30 min. Corticotropin-releasing factor (CRF) (63-210 pmol) microinjected into the DVC concomitantly with RX 77368 (26 pmol) induced a dose-related inhibition of stimulated gastric contractility. Neither CRF alone (210 pmol) nor vehicle modified basal gastric contractility. Microinjection of kainic acid (141 pmol) into the raphe pallidus nucleus induced a 3.6-fold stimulation of gastric contractility after 45 min. This stimulation was suppressed by bilateral microinjection of CRF (105 pmol/site) into the DVC. These results demonstrate that CRF acts in the DVC to inhibit centrally-stimulated gastric contractility and suggest that TRH and CRF may interact in the DVC to regulate gastric motor function.
Heymann-Mönnikes
I
I
Department Psychiatry and Research, West Los Angeles Veterans Administration Medical Center, CA.
Taché
Y
Y
Trauner
M
M
Weiner
H
H
Garrick
T
T
D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005769:Gastrointestinal Motility / Q000187:drug effects*; D007608:Kainic Acid / Q000494:pharmacology*; D008297:Male; D008526:Medulla Oblongata / Q000187:drug effects / Q000502:physiology*; D008845:Microinjections; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D009928:Organ Specificity; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives; D011903:Raphe Nuclei / Q000187:drug effects / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D013270:Stomach / Q000187:drug effects / Q000502:physiology; D013973:Thyrotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D014630:Vagus Nerve / Q000187:drug effects / Q000502:physiology*
D013973:Thyrotropin-Releasing Hormone; C027979:L-pyroglutamyl-L-histidyl-3,3-dimethylprolinamide; D003346:Corticotropin-Releasing Hormone; D007608:Kainic Acid; D011761:Pyrrolidonecarboxylic Acid