Fat-Soluble Vitamins

Abstract

Annu. Rev. Biochem. 1942.11:365-390. Downloaded from www.annualreviews.org Access provided by University of California -San Francisco UCSF on 02/03/15. For personal use only. Quick links to online content Further ANNUAL REVIEWS ing out such tests on the nonsaponifiable fraction of the reference oil, Annu. Rev. Biochem. 1942.11:365-390. Downloaded from www.annualreviews.org Access provided by University of California -San Francisco UCSF on 02/03/15. For personal use only. Annu. Rev. Biochem. 1942.11:365-390. Downloaded from www.annualreviews.org Access provided by University of California -San Francisco UCSF on 02/03/15. For personal use only.

A histological method for the biological estimation of vitamin A

“…The resulting bony overgrowth caused pressure on the central nervous system and peripheral nerves by squeezing and stretching and resulted in degeneration due to mechanical injuries. Wolbach & Bessey (1940, 1942 and Moore & Sykes (1941) agreed with Mellanby that degeneration was caused by mechanical injuries due to pressure. They, however, ascribed this to causes other than bone growth.…”

“…That loss of weight alone does not account for paralysis or degeneration in the cord, was shown by several workers (Aberle, 1934;Wolbach & Bessey, 1940, 1942). Rats received a diet adequate in vitamin A but restricted in amount, so that their weights paralleled those of litter mates on a vitamin A-deficient diet.…”

“…There are considerable differences between physicochemical and biological results of vitamin A estimations, owing to the fact that the 'analyst determines the proportion of a substance present, whilst the bioassayist determines an effect' (Morton, 1942). The biological vitamin A value of food or pharmaceutical products is the sum of the values of all substances present havingvitamin A activity, such as preformed vitamin A, either as the free alcohol or esters, and various carotenoid pigments.…”