Effects of central injection of L-carnosine on sympathetic nerve activity innervating brown adipose tissue and body temperature in rats.
In the present study, using urethane-anesthetized rats, we examined the effects of intralateral cerebral ventricular (LCV) injection of various doses of L-carnosine on neural activity innervating brown adipose tissue (BAT-SNA) and body temperature (BT). We found that injection of a low dose of L-carnosine (0.01 microg) suppressed BAT-SNA significantly. Conversely, a high dose (100 microg) of L-carnosine significantly elevated BAT-SNA. In the light period (14:00), brown adipose tissue temperature (BAT-T) and BT were suppressed after low and elevated after high dose injection of L-carnosine whereas in the dark period (2:00), these parameters remained unchanged with L-carnosine treatment. Bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) abolished the effects of low and high doses of L-carnosine on BAT-SNA, BAT-T and BT. Furthermore, high dose treatment with L-carnosine altered c-Fos induction in the SCN and the PVN. These results suggest that l-carnosine affects BAT-SNA, BAT-T and BT in a dose-dependent manner in the rat, and that the SCN may be involved in these effects.
Tanida
Mamoru
M
Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan. mtanida@anbas.co.jp
Gotoh
Hitoshi
H
Taniguchi
Hiroyuki
H
Otani
Hiroto
H
Shen
Jiao
J
Nakamura
Takuo
T
Tsuruoka
Nobuo
N
Kiso
Yoshinobu
Y
Okumura
Nobuaki
N
Nagai
Katsuya
K
D002001:Adipose Tissue, Brown / Q000187:drug effects* / Q000294:innervation* / Q000378:metabolism; D018686:Anesthetics, Intravenous / Q000494:pharmacology; D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D002336:Carnosine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013564:Sympathetic Nervous System / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D014520:Urethane / Q000494:pharmacology
D018686:Anesthetics, Intravenous; D014520:Urethane; D002336:Carnosine