[Anti-inflammatory, analgesic and sedative effects of Leontice kiangnanensis P.L. Chiu]

The ethanolic extract of Leontice kiangnanensis (EELK) can inhibit obviously the increased permeability of abdominal blood capillaries and the ear inflammation in mice as well as the swelling of hind paw and the proliferation of granuloma induced by cotton-pellets in rats, EELK can also raise the pain thresholds during hot-plate, formaldehyde and writhing tests in mice. Use of EELK together with pentobarbital may enhance sedative effect on mice.

Metabolism of normal skeletal muscle during dynamic exercise to clinical fatigue: in vivo assessment by nuclear magnetic resonance spectroscopy

In vivo nuclear magnetic resonance (NMR) spectroscopy was used to define several intracellular high energy phosphate variables of the gastrocnemius muscle of normal subjects during rest, graded plantar flexion exercise to exhaustion, and recovery. There were nine males and eight females with an average age of 34 +/- 8 years. At rest, pH averaged 7.09 +/- 0.03 and the energy cost index (ECI)--the ratio of inorganic phosphate to phosphocreatine--averaged 0.13 +/- 0.03. At peak exercise, the ECI increased markedly to 2.71 +/- 2.0 (P less than 0.001) and pH fell precipitately to 6.76 +/- 0.17 (P less than 0.001), indicating the high intensity of the exercise. Exercise endurance averaged 12 +/- 5 mins; it was not highly correlated with sex, age (r = 0.35), rest pH (r = 0.26), rest ECI (r = 0.38), peak exercise pH (r = 0.23) or peak exercise ECI (r = 0.38), nor exercise changes in pH (r = 0.17) and ECI (r = 0.28). At 23 mins post exercise all variables were similar to rest. Rest pH was the only variable different between males (7.10 +/- 0.03) and females (7.07 +/- 0.03) (P less than 0.05). Thus, dynamic exercise of large skeletal muscles in normal subjects was characterized by marked temporal changes in high energy phosphate profiles and very low pH at exhaustion. No single metabolic variable correlated highly with exercise endurance, suggesting that the intracellular pathophysiology of exhaustive muscle exercise and clinical fatigue may be multifactorial.

[Effects of Codonopsis pilosulae on the synthesis of thromboxane A2 and prostacyclin]

24 angina pectoris patients were treated with Codonopsis pilosulae (CP) oral solution 20 ml (containing crude CP 20 g) thrice daily for 7 days, other 10 cases were treated by aspirin 0.5 g per day for a week as the control group. After treatment, in the CP group, the plasma level of TXB2 was obviously reduced from 156.76 +/- 11.87 pg/ml to 125.01 +/- 8.85 pg/ml (means +/- S means), the inhibitory rates was 15. 67% (P less than 0.05), and of 6-keto-PGF1 alpha (6-K) was not markedly changed (P greater than 0.05). In the aspirin group, TXB2 was also reduced significantly (P less than 0.05); 6-K was reduced more than that of CP group, the inhibitory rate was 24.33 +/- 9.40% (P less than 0.05). To reveal the mechanism of CP action on the synthesis of TXA2 and PGI2, the porcine lung microsome was used as the donor of cyclooxygenase, thromboxane synthase and prostacyclin synthase, the effects of CP on the formation of TXB2 and 6-K from arachidonic acid (AA) or endoperoxides were measured by RIA respectively. The results showed that both the levels of the formation of TXB2 from AA or endoperoxides were markedly reduced by CP in a dose-dependent (at doses of 3-300 mg/ml). The synthesis of TXB2 was distinctly inhibited alone with a dose of 100 mg/ml CP, which suggested that CP might be an inhibitor of TXB2 synthase at that dose; while at a dose of 300 mg/ml CP, the synthesis of TXB2 and 6-K were inhibited simultaneously (P less than 0.001). It showed that a larger dosage of CP, which could inhibited the synthesis of both TXA2 and PGI2, its mechanism of action needs further study.

Status of the substrate binding sites of ribulose bisphosphate carboxylase as determined with 2-C-carboxyarabinitol 1,5-bisphosphate

The properties of the tight and specific binding of 2-C-carboxy-d-arabinitol 1,5-bisphosphate (CABP), which occurs only to reaction sites of ribulose 1,5-bisphosphate carboxylase (Rubisco) that are activated by CO(2) and Mg(2+), were studied. With fully active purified spinach (Spinacia oleracea) Rubisco the rate of tight binding of [(14)C]CABP fit a multiple exponential rate equation with half of the sites binding with a rate constant of 40 per minute and the second half of the sites binding at 3.2 per minute. This suggests that after CABP binds to one site of a dimer of Rubisco large subunits, binding to the second site is considerably slower, indicating negative cooperativity as previously reported (S Johal, BE Partridge, R Chollet [1985] J Biol Chem 260: 9894-9904). The rate of CABP binding to partially activated Rubisco was complete within 2 to 5 minutes, with slower binding to inactive sites as they formed the carbamate and bound Mg(2+). Addition of [(14)C]CABP and EDTA stopped binding of Mg(2+) and allowed tight binding of the radiolabel only to sites which were CO(2)/Mg(2+)-activated at that moment. This approach estimated the amount of CO(2)/Mg(2+)-activated sites in the presence of inactive sites and carbamylated sites lacking Mg(2+). The rate of CO(2) fixation was proportional to the CO(2)/Mg(2+)-activated sites. During light-dependent CO(2) fixation with isolated spinach chloroplasts, the amount of carbamylation was proportional to Rubisco activity either initially upon lysis of the plastids or following total activation with Mg(2+) and CO(2). Lysis of chloroplasts in media with [(14)C]CABP plus EDTA estimated those carbamylated sites having Mg(2+). The loss of Rubisco activation during illumination was partially due to the lack of Mg(2+) to stabilize the carbamylated sites.

SV40-transfected human melanocyte sensitivity to growth inhibition by the phorbol ester 12-O-tetradecanoylphorbol-13-acetate

Normal human melanocytes, which require the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) for growth in culture, were transfected with a SV40 T-antigen-containing plasmid by using the technique of electroporation, and were scored for colonies of morphologically altered cells. The frequency of transformed colonies was higher when selection was done in the absence rather than the presence of TPA in the medium. Three cell lines derived from transformed colonies were characterized. All show an enhanced growth rate compared to parental cells, anchorage independence, loss of dependence on medium supplements for growth, chromosomal abnormalities, an extended life span, and growth inhibition by TPA. They express nerve growth factor receptor and Mr 97,000 protein, melanotransferrin, two antigens usually associated with melanocytic cells, but the transformed cells are not pigmented. The three cell lines underwent crisis at about passage 10 posttransfection; one cell line recovered and appears to have unlimited growth potential. None of the cell lines is tumorigenic. They should be interesting models for studying multistage carcinogenesis in human cells and transcriptional activation by TPA.