TY - JOUR
T1 - Effect of celiac ganglionectomy on tachykinin innervation, receptor distribution and intestinal responses in the rat
AU - Ouyang, Ann
AU - Zimmerman, Karl
AU - Wong, Kar Lais
AU - Sharp, Douglas
AU - Reynolds, James C.
N1 - Funding Information:
This work was supported in part by NIH Grant R01 DK34148-06. Kar-Lai Wong was supported by an NIH funded Short-term Experience in Research Program, and Karl Zimmerman was supported by a Student Research Fellowship, American Gastroenterological Association.
PY - 1996/12/14
Y1 - 1996/12/14
N2 - Substance P (SP) is an important neurotransmitter in the control of intestinal motility and is found in both the enteric and sympathetic nervous systems. This study examined the effect of celiac ganglionectomy on (1) mechanical properties of the circular muscles of the duodenum, ileum and proximal colon, (2) circular muscle responses to SP and neurokinin A, (3) distribution of substance P-like immunoreactive nerves, and (4) the distribution of neurokinin 1 and neurokinin 2 receptors. Celiac ganglionectomy resulted in an effective sympathectomy as evidenced by a marked decrease in norepinephrine content and tyrosine hydroxylase staining in the duodenum, ileum and proximal colon. The in vitro length/tension characteristics of the circular muscle of the duodenum, ileum and colon were unchanged after ganglionectomy. In all regions of the gut studied, substance P and neurokinin A caused dose-dependent contractions that were unaltered by celiac ganglionectomy. Immunohistochemistry revealed moderate substance P-like immunoreactive fibers in the myenteric plexus, submucosal plexus and circular muscle of the ileum, while in the colon, substance P-like immunoreactivity was intense in the myenteric plexus, and moderate in the circular muscle. In vitro autoradiography showed minimal binding of SP (NK1 receptor) or neurokinin A (NK2 receptor) in the ileum and significantly greater binding in the circular muscle layer of the colon. Celiac ganglionectomy did not affect substance P-like immunoreactivity, or NK1 or NK2 receptor binding. A greater contractile response to neurokinins was seen in the colon than in the duodenum or ileum, which paralleled the receptor density. The studies demonstrate that surgical celiac ganglionectomy, unlike chemical sympathectomy, does not affect the substance P innervation, receptor density or physiological responses of the intestine. The greater contractile response of the colon than the ileum parallels the greater receptor density rather than the peptide content as determined by immunohistochemistry.
AB - Substance P (SP) is an important neurotransmitter in the control of intestinal motility and is found in both the enteric and sympathetic nervous systems. This study examined the effect of celiac ganglionectomy on (1) mechanical properties of the circular muscles of the duodenum, ileum and proximal colon, (2) circular muscle responses to SP and neurokinin A, (3) distribution of substance P-like immunoreactive nerves, and (4) the distribution of neurokinin 1 and neurokinin 2 receptors. Celiac ganglionectomy resulted in an effective sympathectomy as evidenced by a marked decrease in norepinephrine content and tyrosine hydroxylase staining in the duodenum, ileum and proximal colon. The in vitro length/tension characteristics of the circular muscle of the duodenum, ileum and colon were unchanged after ganglionectomy. In all regions of the gut studied, substance P and neurokinin A caused dose-dependent contractions that were unaltered by celiac ganglionectomy. Immunohistochemistry revealed moderate substance P-like immunoreactive fibers in the myenteric plexus, submucosal plexus and circular muscle of the ileum, while in the colon, substance P-like immunoreactivity was intense in the myenteric plexus, and moderate in the circular muscle. In vitro autoradiography showed minimal binding of SP (NK1 receptor) or neurokinin A (NK2 receptor) in the ileum and significantly greater binding in the circular muscle layer of the colon. Celiac ganglionectomy did not affect substance P-like immunoreactivity, or NK1 or NK2 receptor binding. A greater contractile response to neurokinins was seen in the colon than in the duodenum or ileum, which paralleled the receptor density. The studies demonstrate that surgical celiac ganglionectomy, unlike chemical sympathectomy, does not affect the substance P innervation, receptor density or physiological responses of the intestine. The greater contractile response of the colon than the ileum parallels the greater receptor density rather than the peptide content as determined by immunohistochemistry.
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U2 - 10.1016/S0165-1838(96)00099-9
DO - 10.1016/S0165-1838(96)00099-9
M3 - Article
C2 - 8988488
AN - SCOPUS:0030583835
SN - 0165-1838
VL - 61
SP - 292
EP - 300
JO - Journal of the Autonomic Nervous System
JF - Journal of the Autonomic Nervous System
IS - 3
ER -