URINARY ADRENOCORTICAL STEROIDS: III. FORMALDEHYDOGENIC SUBSTANCES LABILE IN ACID SOLUTION AT ROOM TEMPERATURE

Abstract

Hydrolysis of urine at pH 1 and room temp. for periods of 1.5-3 hrs. was found to increase significantly the formaldehyde-retaining powers of unwashed CHCl3 extracts. It is considered that this phenomenon may account in part for the apparent destruction of formaldehydogenic substances (FSS) observed by Paterson, Cox and Marrian (1950) in expts. in which unwashed extracts of urine acidified to pH 1 were employed. When alkali washing of the CHCl3 extracts was employed, treatment of the urine at pH 1 and room temp. for periods up to 4 hrs. was found to result only occasionally in apparent decreases in the yields of extractable neutral FSS. It was shown, however, that these decreases were not due to increases in the formaldehyde-retaining powers of the extracts. Part of the unconjugated FSS in NaHCO3- washed CHCl3 extracts of unacidified urine is highly labile in aqueous soln. at pH 1 and room temp. The range of amts. of the cold acid-labile FSS in the urine of normal men is equivalent to 8.4-27.4 [mu]g- HCHO per 24 hrs. The extraction of unconjugated cold acid-labile FSS markedly increased by the admn. of ACTH. In whole urine acidified to pH 1 and allowed to stand at room temp. for periods of a few hrs., the destruction of unconjugated cold acid-labile FSS is partially or completely masked by the simultaneous liberation of neutral cold acid-stable FSS from conjugated FSS. For this reason it is not possible to demonstrate with regularity either the destruction of cold acid-labile FSS or the hydrolysis of conjugated FSS by expts. on acidified whole urine. In contrast to the findings of previous workers, acidification of urine to pH 1 "immediately" before extraction with CHCl3 was not found to result in any significant increase in the yields of neutral FSS. A procedure is descr. for overcoming the error in the detn. of urinary FSS due to retention of formaldehyde by interaction with substances present in CHCl3 extracts.