Regional changes in brain histamine levels following dietary-induced thiamine deficiency in rats.

Effects of Thiamine Administration on Hypothermia and Hypothalamic Histamine Levels in Dietary-Induced Thiamine Deficient Rats

“…The present biochemical data that thiamine deficiency resulted in a marked increase in histamine levels of both the anterior and posterior hypothalamus are consistent with our previous report (4). It was notable that the histamine levels in the anterior hypo thalamus were higher than those in the posterior hypothalamus in the thiamine (-) diet group.…”

“…We have recently reported that the thiamine deficiency im paired the activity of central histaminergic neurons and resulted in a significant increase in the histamine levels in the hypothalamus (4). Previous studies showed that central administration of histamine caused hypo thermia in many animal species and that both Hj and H2-receptors in the brain seemed to be involved in the hypothermia (5 11).…”

“…The rats were housed individually in a mesh cage (17 x 25 x 37 cm) and divided into the following two dietary treatment groups until day 30: 1) Thiamine-deficient group (thia mine (-) diet group): The animals were fed powdered thiamine-deficient diet (Funabashi Farm Co.) containing 67.6% carbohydrate, 18% protein, 8% lipids, and necessary vita mins (without thiamine) and minerals (3,4). 2) Thiamine-added group (thiamine (+) diet group): The animals were fed the same diet as in the thiamine (-) diet group, but containing 0.5 mg of thiamine hydrochloride per 100 g of diet.…”

“…Twenty-four hours after the administration of thiamine disulfide, the rectal temperature of the rats were recorded; and then these rats were immediately sacri ficed by decapitation, and their brains were quickly removed on ice. The anterior hypo thalamus, posterior hypothalamus and pitui tary were dissected, and the histamine con tents of these regions were measured by the HPLC-fluorometric method as described pre viously (4,12). After the single injection of thiamine disulfide, some of the rats in thi amine (-) diet group were maintained further on the thiamine (+) diet for 30 days, and histamine levels in the hypothalamus and pituitary were measured in the same way as above at the end of the experiment.…”

Effects of d-, l- and dl-Chlorpheniramine on Dopamine and 3,4-Dihydroxyphenylacetic Acid Levels in the Regional Parts of Rat Brain.

“…The rats were decapitated at defined intervals after the injections, and their brains were quickly removed and dissected on ice into regional parts by the method of Glowinski and Iversen (1966) with a slight modification (Onodera et al 1988), frozen on dry ice, and stored in a deep freezer until assay (-80°C). After homogenization of brain samples in 0.4 N perchloric acid containing 2 mM EDTA by a sonicator (Sonifier 450; BRANSON, Danbury, CT, USA) for 10 sec in an ice bath, the homogenate was centrifuged at 10,000 x g for 20 min at 4°C, and then stored at -80°C until use.…”