Category Archives: Male Rat Reproductive Tract

Creatine Synthesis and Transport Systems: DISCUSSION(5)

Seminal Vesicles No significant amounts of transamidinase, GAMT, or AdoHcyase mRNAs were observed in the seminal vesicles of rats (Figs. 2, 4, and 5). Transamidinase protein was not detected by immunoblotting (Fig. 3, A and B), and GAMT activity was … Continue reading

Creatine Synthesis and Transport Systems: DISCUSSION(4)

Epididymis There have not been any reports of GAMT or transamidinase activities in the epididymis, but we previously have shown that very high levels of GAMT mRNA and protein are expressed in the mouse caput epididymidis and low levels in … Continue reading

Creatine Synthesis and Transport Systems: DISCUSSION(3)

Besides metabolizing AdoHcy, AdoHcyase may have another important function: namely, producing adenosine and homocysteine. Others have reported considerable levels of AdoHcyase activity in the testis. Although sperm cells have AdoHcyase activity, we suspect that AdoHcyase may be expressed by the … Continue reading

Creatine Synthesis and Transport Systems: DISCUSSION(2)

Alekseeva and Arkhange’skaya could not detect guanidinoacetate synthesis in rat testicular tissue cultured in a medium containing 14C-glycine, whereas guanidinoacetate as well as Cr was labeled by 14C-arginine in both in vivo and in vitro experiments. David and Reddy reported … Continue reading

Creatine Synthesis and Transport Systems: DISCUSSION(1)

Testis The mammalian testis has long been known to be one of the major sources of Cr in the body. In addition, several researchers have shown that testicular tissue is capable of synthesizing Cr from glycine and arginine. We have … Continue reading

Creatine Synthesis and Transport Systems: RESULTS(3)

AdoHcyase catalyzes the breakdown of AdoHcy, the product of GAMT-catalyzed transmethylation reaction using AdoMet as the methyl group donor. Since the hydrolysis of AdoHcy produces homocysteine and adenosine, an important regulatory molecule, we examined the expression pattern of AdoHcyase in … Continue reading

Creatine Synthesis and Transport Systems: RESULTS(2)

In agreement with the immunoblot result, no enzyme activity was detected in testis, seminal vesicle, caput epididymidis, vas deferens, and sperm extracts by the method described previously whereas high transamidinase activity, consistent with previously reported values, was observed in the … Continue reading

Creatine Synthesis and Transport Systems: RESULTS(1)

Transamidinase mRNA and Protein Expression in Kidney and Reproductive Organs Transamidinase is the enzyme that catalyzes the first step of Cr biosynthesis by transferring the amidine group of arginine to glycine to produce guanidinoacetate. Rat kidney transamidinase cDNA was cloned … Continue reading

Creatine Synthesis and Transport Systems: MATERIALS AND METHODS(5)

Reverse transcriptase PCR procedure was utilized for the synthesis of single-strand cDNA probes for transamidinase and Cr transporter mRNAs. Primer pairs for the amplification of transamidinase cDNA fragment (778-bp segment from the 3′ end of the protein coding region to … Continue reading

Creatine Synthesis and Transport Systems: MATERIALS AND METHODS(4)

Synthesis of DIG-Labeled Hybridization Probes DIG-labeled GAMT cRNA probe was prepared from the plasmid pGEM-1 containing rat GAMT cDNA insert by an in vitro transcription reaction using DIG-UTP as described previously. A single-strand antisense DIG-cDNA probe for the AdoHcyase mRNA … Continue reading