[Increased expression of c-fos in the brainstem nuclei involved in cardiova scular regulation by capsaicin].
Effects of intracarotid injected capsaicin on the expression of Fos proto-oncogene in the brainstem nuclei involved in cardiovascular regulation were examined in 16 anesthetized rats with sinoaortic denervation. Only a few Fos-like protein immunoreactivity (FLI) neurons were found in the vehicle-control rats. Following intracarotid injection of capsaicin (10 micromol, 0.1 ml), the FLI neurons were markedly increased in nucleus paragigantocellularis lateralis (PGL), locus coeruleus (LC), area postrema (AP) and nucleus tractus solitarius (NTS), as compared with the results of vehicle-control rats, while the FLI neurons of raphe nuclei (RN) and periaqueductal gray (PAG) were not affected. The excitatory response to intracarotid injection of capsaicin was significantly inhibited by pretreatment with the vanilloid receptor (capsaicin receptor) antagonist ruthenium red (200 mmol, 0.1 ml). The results indicate that capsaicin may activate the neurons of the brainstem nuclei involved in cardiovascular regulation through vanilloid receptors, but does not exert any effects on PAG and RN.
Xue
B J
BJ
Department of Physiology and Hebei Medical University, Shijiazhuang 050017, China.
Zhang
X X
XX
Shi
G M
GM
He
R R
RR
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D001933:Brain Stem / Q000378:metabolism*; D002211:Capsaicin / Q000494:pharmacology*; D017536:Carotid Artery, Common; D006339:Heart Rate / Q000502:physiology; D007269:Injections, Intra-Arterial; D008125:Locus Coeruleus / Q000378:metabolism; D008297:Male; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017552:Solitary Nucleus / Q000378:metabolism
D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D002211:Capsaicin