Interleukin 1 beta-induced increase in substance P in rat myenteric plexus.
BACKGROUND
Substance P (SP) is increased in the inflamed intestine of Trichinella spiralis-infected rats, but the underlying mechanism is unknown. Interleukin 1 beta (IL-1 beta) messenger RNA and protein is expressed in the longitudinal muscle-myenteric plexus (LM-MP) of this model. Thus, the purpose of the study was to examine the ability of human recombinant IL-1 beta (hrIL-1 beta) to increase SP in LM-MP preparations from the intestine of noninfected rats.


METHODS
LM-MP preparations were incubated with hrIL-1 beta, and immunoreactive SP (IR-SP) was assessed in the tissues by radioimmunoassay or immunohistochemistry.


RESULTS
hrIL-1 beta increased IR-SP in the tissue in a time- and concentration-dependent manner, being maximal after 6 hours at a concentration of 10 ng/mL. The IR-SP could be depleted by scorpion venom, and immunohistochemistry revealed increased staining for SP within nerves of the LM-MP. The action of IL-1 beta was dependent on protein synthesis, was receptor mediated, and was not due to endotoxin contamination of the cytokine preparation.


CONCLUSIONS
hrIL-1 beta stimulates the synthesis of SP in myenteric nerves of rat intestine.
Hurst
S M
SM
Intestinal Diseases Research Unit, McMaster University, Hamilton, Ontario, Canada.
Stanisz
A M
AM
Sharkey
K A
KA
Collins
S M
SM
D000818:Animals; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D009197:Myenteric Plexus / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology; D013373:Substance P / Q000032:analysis / Q000096:biosynthesis*
D007375:Interleukin-1; D011994:Recombinant Proteins; D013373:Substance P