[Inhibition of gastric motility by microinjection of CCK-8 into rat amygdala].
Intranulear microinjection and electrical stimulation technique were employed to evaluate the effect of ventromedial hypothalamus (VMH) on the gastric inhibition elicited by basomedial amygdala nucleus (BMA) excitation. The results were as follows: (1) Microinjections of CCk-8 (50 ng/microliter) into bilateral BAM resulted in significant decrease in intragastric pressure (IGP) and gastric motility frequency (GMF) (P < 0.01). (2) Neither CCK-A receptor antagonist [L364, 718] nor CCK-8 receptor antagonist [L365, 260] induced effects on IGP or GMF when given alone. (3) If bilateral BMA were pretreated with [L364, 718], CCK-8 could no longer induce any inhibitory effects, whlie [L365, 260] had no similar suppressive effect. (4) The inhibitory effects were not found in other nuclei in the amygdaloid body, such as bed nucleus of the stria terminalis intramygdaloid (BSTIA) and amygdaloid nucleus medial (Me). (5) Electrical stimulation of unilateral VMH or BMA would result in the inhibition of IGP and GMF. (6) After electric coagulation of VMH unilateraly injection of CCK-8 to or stimulation of homolateral VMH could no longer inhibite IGP or GMF. The above results suggest that in BMA CCK-8 exerts inhibitory effect on both motility and intragastric pressure through CCK-A receptors.
Tang
M
M
Department of Physiology, Medical College of Qingdao University.
Su
H L
HL
Li
C L
CL
D000679:Amygdala / Q000502:physiology*; D000818:Animals; D003864:Depression, Chemical; D004558:Electric Stimulation; D005769:Gastrointestinal Motility / Q000187:drug effects*; D008297:Male; D008845:Microinjections; D011312:Pressure; D051381:Rats; D012844:Sincalide / Q000494:pharmacology*; D013270:Stomach / Q000502:physiology*
D012844:Sincalide