An anhydrous color reagent containing ferric chloride is pumped through Tygon tubing to a glass coil in a 95° heating bath. Manually prepared serum extracts (1:20 isopropanol dilution) are presented to the stream of preheated color reagent, and the two are passed through three mixing coils, connected in series. The absorbance of the resultant color is determined at 550 mµ in a 15 mm. tubular flow-cell. The improved N-automated procedure gave values of greater precision (5.6%) for total cholesterol determined in replicate samples from sera pools than the N-automated procedure which lacked precision (27.7%). The values found in 60 individual serums are within 6.0% of total cholesterol values determined by the Abell et al. method.
his experiment examined the influence of plasma corticosterone on stress-induced ulceration in restrained rats. Gastric pathology and plasma corticosterone levels were examined in normal (UNOP) and adrenalectomized (ADX) rats under two conditions of shock predictability. The severity of the gastric ulceration in unoperated rats given noncontingent presentations of a tone and an electric shock was greater than in subjects receiving shocks contingent upon CS presentation. When ulcer pathology was evaluated for ADX animals, no differences were found between the predictable and the unpredictable shock groups. The results were discussed in terms of the necessary and sufficient conditions for stomach ulcer formation as a function of shock predictability and restraint stress and the necessity to investigate alternative hypotheses. Recent evidence has suggested that several physiological mechanisms contribute to gastric ulcer formation in restrained rats. Weiss (1968; 1970) has
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.