THE CHARACTERIZATION OF POLAR CORTICOSTEROIDS IN THE URINE OF THE MACAQUE MONKEY (MACACA FASCICULARIS) AND THE BABOON (PAPIO HAMADRYAS)

ABSTRACT Computerised gas chromatography-mass spectrometry was employed in the identification of polar corticosteroid metabolites excreted in the urine from the macaque monkey (Macaca fascicularis) and the baboon (Papio hamadryas). The following steroids were identified in significant amounts in the urine from both species: 3α,17α,20α,21-tetrahydroxy-5β-pregnan-11-one; 3α,17α,20β,21-tetrahydroxy-5β-pregnan-11-one; 5β-pregnane-3α,11β,17α,20α,21-pentol; 5β-pregnane-3α,11β,17α,20β-pentol; 5α-pregnane-3β, 11β, 17α,20β,21 -pentol. 11β,17α,21-Trihydroxy-4-pregnene-3,20-dione (cortisol), 11β,17α,20β,21-tetrahydroxy-4-pregnen-3-one and 11β, 17α,20β,21 -tetrahydroxy-5ξ-pregnan-3-one were identified in macaque monkey urine. Two steroids, 17α,20β,21-trihydroxy-4-pregnane-3,11-dione and 17α,20α,21-trihydroxy-4-pregnene-3,11-dione were excreted as major C21 metabolites in the baboon but were not identified in the urine from the macaque monkey. 3β-Hydroxy-5α-pregnane metabolites were identified in the urine from both species. All these steroids were excreted conjugated to glucuronic acid, evidenced by their recovery after hydrolysis with β-glucuronidase enzyme. An efficient 20β-reduction of corticosteroids in both species is apparent, and the excretion pattern of polar steroid metabolites in the two species was shown to be similar.