当前位置： SCI文献检索 > NEUROSCIENCE期刊下所有文献 > Selective blockade of substance P or neurokinin A receptors reduces the expression of c-fos in trigeminal subnucleus caudalis after corneal stimulation in the rat.

Selective blockade of substance P or neurokinin A receptors reduces the expression of c-fos in trigeminal subnucleus caudalis after corneal stimulation in the rat.

Abstract：

:Stimulation of the cornea activates neurons in two distinct regions of the spinal trigeminal nucleus: at the transition between trigeminal subnucleus interpolaris and subnucleus caudalis and at the transition between trigeminal subnucleus caudalis and the upper cervical spinal cord as estimated by expression of the immediate early gene, c-fos. To determine if receptors for substance P or neurokinin A, neurokinin 1 and neurokinin 2 receptors, respectively, contribute to the production of Fos-positive neurons in these brainstem regions, receptor-selective antagonists were given intracerebroventricularly 15 min prior to stimulation of the cornea in anesthetized rats. The number of Fos-positive neurons produced in superficial laminae at the trigeminal subnucleus caudalis/cervical cord transition by application of the selective small fiber excitant, mustard oil, to the corneal surface was reduced by the neurokinin 1 receptor antagonist, CP99,994 (5-100 nmol, i.c.v.) and the neurokinin 2 receptor antagonist, MEN10,376 (0.01-1.0 nmol, i.c.v.). Combined pretreatment with CP99,994 and the competitive N-methyl-D-aspartate receptor antagonist, CPP, caused a greater reduction in c-fos expression at the subnucleus caudalis/cervical cord transition than after either drug alone suggesting interaction between receptors for glutamate and substance P. Tachykinin receptor antagonists did not reduce the number of Fos-positive neurons produced at the subnucleus interpolaris/subnucleus caudalis transition. The elevation in plasma concentration of adrenocorticotropin, but not the increases in arterial pressure or heart rate, evoked by corneal stimulation was prevented by pretreatment with CP99,994 or MEN10,376 at doses lower than those needed to reduce c-fos expression. The results indicate that receptors for substance P and neurokinin A contribute to the transmission of sensory input from corneal nociceptors to brainstem neurons in trigeminal subnucleus caudalis and to increased activity of the hypothalamo-pituitary axis that accompanies acute stimulation of the cornea.

journal_name

Neuroscience

journal_title

Neuroscience

authors

Bereiter DA,Bereiter DF,Tonnessen BH,Maclean DB

doi

10.1016/s0306-4522(97)00433-8

subject

Has Abstract

pub_date

1998-03-01 00:00:00

pages

525-34

issue

eissn

0306-4522

issn

1873-7544

pii

S0306452297004338

journal_volume

pub_type

杂志文章

在线工具

Selective blockade of substance P or neurokinin A receptors reduces the expression of c-fos in trigeminal subnucleus caudalis after corneal stimulation in the rat.