Histamine at high dilution reduces spectral density in delta band in sleeping rats.
Histamine is a central neurotransmitter, it increases arousal via H1 receptors. This study examines the effect of ultra-diluted histamine on arousal through changes in the sleep pattern of Wistar rats. The spectral density in delta (0.5-2.5 Hz) band, one of the three major spectral components of the sleep-electroencephalogram, was analyzed against time. Rats were randomized to receive histamine 30c (histamine 30c, 0.05 ml every 20 min during the first 2 h orally), histamine intraperitoneal pre-treatment/histamine 30c (histamine 6mg/kg i.p., followed by histamine 30c) or solvent control. The mean delta band spectral density was lower in the histamine 30c and histamine pretreatment/histamine 30c groups than the control group. Significant differences between histamine 30c and baseline during the first 2 h imply an immediate effect. These results also suggest a dynamic process in which the system spontaneously evolves between two locally stationary states according to a power law. From the time perspective, the system approaches, asymptotically, an equifinal state.
Ruiz-Vega
G
G
Laboratorio de Biofísica, Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México. ruizvega@ifm.umich.mx
Poitevin
B
B
Pérez-Ordaz
L
L
D000284:Administration, Oral; D000704:Analysis of Variance; D000818:Animals; D001143:Arousal / Q000187:drug effects*; D003700:Delta Rhythm / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006632:Histamine / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012894:Sleep Stages / Q000187:drug effects*; D013997:Time Factors
D006632:Histamine