Amino acid content of rabbit urine and plasma.

The content of amino acids in plasma and urine from male albino rabbits was determined by ion-exchange chromatography and compared to values for other species. In general, the amino acids present, in the plasma and urine of rabbits are those commonly found in other species. In contrast to human urine in which t,he cont,ent of hi&dine is usually greater than the two methylated derivatives, the content of histidine in rabbit urine is lower than tither 1-methylhistidine or 3-met,hylhistidinf~. The plasma amino acid pattern is unusual in that glycinc content is higher than alanine content; this is the reverse of the pattern in man and the cat. Fasting the rabbits for 88 hr. cxused approximately a 66% decrease in the total amount of urinary amino acids. A 12or 8%hr. fast caused the plasma total amino acid content to decrease approsimatc~ly 30% T’aline. isoltTlu%, and leucine conients of the plasma, howevc>r, were increased.