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Biomedical subjects

G Zou

Publications and source records attributed to G Zou.

33 records · Page 2Linked to original sources
PubMed1989

Isolation and structure of ranamargarin, a new tachykinin from the skin of Chinese frog Rana margaratae.

A new tetradecapeptide, ranamargarin, has been isolated by Sep-Pak C18 and HPLC from methanol extracts of the skin of the Chinese frog Rana margaratae. The sequence of the peptide is: Asp-Asp-Ala-Ser-Asp-Arg-Ala-Lys-Lys-Phe-Tyr-Gly-Leu-Met-NH2. This structure has been confirmed by synthesis. The peptide is the largest among the amphibian tachykinins and its N-terminal amino acids are quite different from those of the other tachykinins. The formation of the sulfoxide and peak-splitting of ranamargarin during purification procedures are briefly discussed.

Amino Acid Sequence↗
PubMed1988

Electro-acupuncture markedly increases proenkephalin mRNA in rat striatum and pituitary.

Electro-acupuncture (EA) has been found to increase enkephalin content in striatum, hypothalamus and cerebrospinal fluid. Further studies on rat striatum showed that the increase is accompanied by an elevation of enkephalin precursor and processed intermediate levels. In order to characterize the nature of these changes, we have measured the proenkephalin mRNA (PE-mRNA) level in rat striatum and pituitary by recombinant DNA technique. The PE-mRNA was hybridized with human proenkephalin cDNA using a dot-blot procedure. Rats receiving EA showed a 3-5-fold increase of PE-mRNA in striatum beginning at 1 h after the cessation of 30-min EA treatment and lasting 48 h at least. A 3-fold increase of PE-mRNA in pituitary was found immediately after the cessation of EA and a 5-6-fold increase at 1 or 24 h after the termination of EA.

Acupuncture Therapy↗
PubMed1983

Determination of catecholamines in human serum by micro high-performance liquid chromatography with micro precolumn and dual electrochemical detection.

A dual electrochemical detector having two working electrodes (anode and cathode) in parallel--opposed configuration suitable for micro high-performance liquid chromatography was developed for the selective and sensitive detection of catecholamines on the basis of their electrochemical reversibility and catalytic amplification by recycling oxidation and re-reduction. The micro high-performance liquid chromatographic system with a micro alumina precolumn for enriching catecholamines and the dual electrochemical detector in parallel--opposed configuration was successfully utilized for the determination of catecholamines in healthy human serum injected directly after ultrafiltration.

Catecholamines↗
PubMed1981

Isolation and partial characterization of two biologically active peptides from porcine spinal cord.

Two biologically active peptides designated SCP-1 and SCP-2 have been isolated and partially characterized from porcine spinal cord. The results of amino acid analysis, electrophoresis, isoelectric focusing and the chromatographic analysis of the dansylated derivatives indicate that these two peptides are homogeneous. The amino acid composition and apparent untriakontapeptide and SCP-2 is a pentacospeptide. The N-terminal amino acids of SCP-1 and SCP-2 are Arginine and Tryptophan respectively. SCP-1 can stimulate the contraction of isolated guinea pig ileum and SCP-2 induces hypotension in anesthetized rat. Both SCP-1 and SCP-2 show no morphine-like activity. The chemical composition and biological properties of SCP-1 and SCP-2 distinguish them from any known peptide.

Amino Acids↗
PubMed1980

Enkephalin involvement in acupuncture analgesia-radioimmunoassay.

Since there are several endogenous morphine-like substances differing in distribution and probably also in function, it seems necessary to study their roles in acupuncture analgesia separately. Therefore we set up a sensitive and specific radioimmunoassay (RIA) for met- and leu-enkephalin, and employ it in determining the changes of enkephalin contents in the brain regions and CSF during acupuncture. The main results are as follows: (i) Two enkephalins increase markedly in hypothalamus and striatum during acupuncture analgesia. (ii) Prior intraventricular bacitracin enhances the acupuncture analgesia with concomitant increased contents of enkephalins in the brain and CSF. (iii) Cycloheximide, the protein-synthesis inhibitor, reduces the enkephalin-increasing effect of acupuncture, indicating that one of the mechanisms by which acupuncture elevates the enkephalin levels is the acceleration of biosynthesis. (iv) After surgical isolation of rat hypothalamus, the effect of electric acupuncture is attenuated. This indicates that hypothalamus takes part in acupuncture analgesia.

Acupuncture Therapy↗