Simultaneous fluorometric measurement of histamine and tele-methylhistamine levels in rodent brain by high-performance liquid chromatography.
An improved high-performance liquid chromatography (HPLC) method was developed for simultaneous analysis of histamine (HA) and tele-methylhistamine (tele-MHA) levels in mouse and rat brain. The method consists of a solid-phase extraction (SPE) and subsequent HPLC with postcolumn derivatization of the amines with o-phthalaldehyde. The recovery rates of HA and tele-MHA during the SPE procedure were 82.8+/-3.4 and 86.0+/-1.7%, respectively. The detection limits for HA and tele-MHA were 8 and 12pg, respectively, with sufficient linearity up to 30pg. Using this newly developed system, we observed that the brain tele-MHA levels in H3 receptor knockout mice were significantly higher than those of wild-type mice by 2.1-fold. Furthermore, we also observed that the brain HA and tele-MHA levels in Zucker rats were significantly lower than those of lean rats by 76.6+/-5.3 and 77.8+/-5.0%, respectively. These observations coincided well with those of previous studies using radioimmunoassay or HPLC with precolumn OPA derivatization, confirming the utilization of the assay system.
Miyamoto
Yasuhisa
Y
BANYU Tsukuba Research Institute, BANYU Pharmaceutical Co., Ltd., Tsukuba, Ibaraki 300-2611, Japan.
Yoshimoto
Ryo
R
Yumoto
Mariko
M
Ishihara
Akane
A
Takahashi
Kazuhiko
K
Kotani
Hidehito
H
Kanatani
Akio
A
Tokita
Shigeru
S
D000447:Aldehydes / Q000737:chemistry; D000588:Amines / Q000737:chemistry; D000818:Animals; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D005470:Fluorometry; D006632:Histamine / Q000032:analysis*; D008297:Male; D008722:Methods; D008761:Methylhistamines / Q000032:analysis*; D051379:Mice; D008813:Mice, Inbred ICR; D018345:Mice, Knockout; D009765:Obesity / Q000378:metabolism; D051381:Rats; D011924:Rats, Zucker; D018100:Receptors, Histamine H3 / Q000235:genetics / Q000502:physiology*
D000447:Aldehydes; D000588:Amines; D008761:Methylhistamines; D018100:Receptors, Histamine H3; D006632:Histamine; C020404:tele-methylhistamine