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Author Brown, J.L.; Wasser, S.K.; Wildt, D.E.; Graham, L.H. url 
  Title Comparative Aspects of Steroid Hormone Metabolism and Ovarian Activity in Felids, Measured Noninvasively in Feces Type Journal Article
  Year 1994 Publication Biol Reprod Abbreviated Journal  
  Volume 51 Issue 4 Pages 776-786  
  Keywords Animal; Carbon; Radioisotopes; Carnivora; Cats; Chromatography; High; Pressure; Liquid; Comparative Study; Estradiol; metabolism; Estrone; feces; chemistry; Female; Ovary; physiology; Pregnancy; Progesterone; Pseudopregnancy; Support; Non-U.S.Gov't; browse; non; government; gov't; us; 170  
  Abstract Noninvasive fecal assays were used to study steroid metabolism and ovarian activity in several felid species. Using the domestic cat (Felis catus) as model, the excretory products of injected [14C]estradiol (E2) and [14C]progesterone (P4) were determined. Within 2 days, 97.0 +/- 0.6% and 96.7 +/- 0.5% of recovered E2 and P4 radioactivity, respectively, was found in feces. E2 was excreted as unconjugated estradiol and estrone (40%) and as a non-enzyme- hydrolyzable conjugate (60%). P4 was excreted primarily as non-enzyme- hydrolyzable, conjugated metabolites (78%) and as unconjugated pregnenolone epimers. A simple method for extracting fecal steroid metabolites optimized extraction efficiencies of the E2 and P4 excretion products (90.1 +/- 0.8% and 87.2 +/- 1.4%, respectively). Analysis of HPLC fractions of extracted fecal samples from the radiolabel-injected domestic cats revealed that E2 immunoreactivity coincided primarily with the unconjugated metabolized [14C]E2 peak, whereas progestogen immunoreactivity coincided with a single conjugated epimer and multiple unconjugated pregnenolone epimers. After HPLC separation, similar immunoreactive E2 and P4 metabolite profiles were observed in the leopard cat (F. bengalensis), cheetah (Acinonyx jubatus), clouded leopard (Neofelis nebulosa), and snow leopard (Panthera uncia). Longitudinal analyses demonstrated that changes in fecal E2 and P4 metabolite concentrations reflected natural or artificially induced ovarian activity. For example, severalfold increases in E2 excretion were associated with overt estrus or exogenous gonadotropin treatment, and elevated fecal P4 metabolite concentrations occurred during pregnant and nonpregnant (pseudopregnant) luteal phases. Although overall concentrations were similar, the duration of elevated fecal P4 metabolites during pseudopregnancy was approximately half that observed during pregnancy. In summary, steroid metabolism mechanisms appear to be conserved among these physically diverse, taxonomically related species. Results indicate that this hormone-monitoring approach will be extremely useful for elucidating the hormonal regulatory mechanism associated with the reproductive cycle, pregnancy, and parturition of intractable and endangered felid species.  
  Address  
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  Series Volume Series Issue Edition  
  ISSN 0006-3363 ISBN Medium  
  Area Expedition Conference  
  Notes Document Type: eng Approved no  
  Call Number SLN @ rana @ 251 Serial 198  
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Author Trepanier, L.A.; Cribb, A.E.; Spielberg, S.P.; Ray, K. url 
  Title Deficiency of cytosolic arylamine N-acetylation in the domestic cat and wild felids caused by the presence of a single NAT1-like gene Type Journal Article
  Year 1998 Publication Pharmacogenetics Abbreviated Journal  
  Volume 8 Issue 2 Pages 169-179  
  Keywords Acetylation; Amino; Acid; Sequence; Animal; Arylamine; N-Acetyltransferase; metabolism; Base; Blotting; Southern; Carnivora; genetics; Cats; Cytosol; enzymology; Dna; Human; Isoenzymes; Liver; Molecular; Data; Polymerase; Chain; Reaction; Rabbits; Homology; Nucleic Acid; Substrate; Specificity; Support; U.S.Gov't; P.H.S.; browse; nucleic; us; government; 130  
  Abstract The purpose of this study was to determine the molecular basis for a relative deficiency in the cat of cytosolic arylamine N- acetyltransferase (NAT), an enzyme family that is important in the metabolism of xenobiotics and that normally consists of at least two related enzymes, NAT1 and NAT2. N-acetyltransferase in feline liver showed high affinity (mean Km = 2.1 microM) for p-aminobenzoic acid, an NAT1 selective substrate in humans and rabbits, but showed a very poor affinity (mean Km > 10 mM) for sulfamethazine, an NAT2 selective substrate in humans and rabbits. Immunoreactive N-acetyltransferase was detected in feline liver, bladder and colon using an NAT1-specific antipeptide antibody, but was not detected in any tissues using an NAT2- specific antibody. Southern blot analysis of genomic DNA demonstrated a single band in domestic cats using each of six restriction digests; single bands were also found on Southern blot analysis of six wild felids. The deduced amino acid sequence of the central portion of feline N-acetyltransferase, obtained by polymerase chain reaction amplification in both domestic cats and seven wild felids (lion, tiger, lynx, snow leopard, bobcat, Asian leopard cat and cheetah), contained three residues, Phe125, Arg127, and Tyr129, which determine NAT1-like substrate specificity in humans. These results support the conclusion that cytosolic arylamine N-acetylation activity is low in the cat because of the presence of a single N-acetyltransferase that has substrate specificity, immunogenicity and sequence characteristics similar to human NAT1, and that the unusual presence of only a single N- acetyltransferase gene appears to be a family wide trait shared by other felids.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0960-314x ISBN Medium  
  Area Expedition Conference  
  Notes Document Type: eng Approved no  
  Call Number SLN @ rana @ 345 Serial 968  
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