The actions of capsaicin applied topically to the skin of the rat on C-fibre afferents, antidromic vasodilatation and substance P levels

1. Single applications of solutions of capsaicin were made to the intact skin of anaesthetized rats and the effects on cutaneous blood flow and the firing of C-nociceptor afferents determined. Blood flow was measured by laser-Doppler flowmetry. C-fibre activity was recorded from filaments dissected from the saphenous nerve. 2. Following the application of a capsaicin solution (concentration > or = 1 mM) to rat saphenous skin, low frequency firing occurred in C-polymodal nociceptors that sometimes continued for > 10 min. At the some time, large increases in skin blood flow occurred exceeding 300% in some instances. 3. After the initial excitation, some C-polymodal nociceptors lost their sensitivity to pressure whilst their sensitivity to heat was lost or enhanced depending on the vehicle used. 4. Sensitivity of C-polymodal nociceptors to heat recovered in < 1 day following a single application of 33 mM capsaicin. Thresholds to mechanical pressure, however, were still significantly elevated by 123% on day 1, but had recovered on day 2. 5. Vasodilatation in response to saphenous nerve stimulation ('antidromic vasodilatation') was significantly reduced by 35%, 2 days after a single application of 33 mM capsaicin, but was normal at 4 days. 6. Following a single application of 33 mM capsaicin, skin substance P levels fell to only half the normal value at day 1 and remained at this level throughout the 4 day period examined. 7. It is suggested that the ability of relatively low concentrations of capsaicin to desensitize C-fibre nociceptors may underlie the analgesic action of topical capsaicin in man.

[Pathogenetic and clinical significance of peripheral activated T-lymphocyte subsets in Basedow's disease]

The peripheral activated T-cell subsets which express concurrently DR and CD antigens were determined in 22 patients with Graves' disease using the fluorescence-rosette double labelling technique. In the active phase of the disease a decrease in the percentage of CD8+ cells, an increase in the CD4+/CD8+ ratio and an elevation of various DR+CD+T-lymphocytes was found. A concurrent marked increase in DR+CD4+ cells accounts for an abnormality in the equilibrium of activated T-lymphocyte subsets and an increase in DR+CD4+/DR+CD8+ ratios. In comparison with the active phase the DR+CD3+ and DR+CD4+ cells decreased in remission, but DR+CD8+ cells remained unchanged. The decrease in the ratio of CD4+/CD8+ cells was less marked than that of the DR+CD4+/DR+CD8+ cells, which fell into the normal range. Our results suggest an excessive activation of T-helper cells as well as a deficiency in T-suppressor cells which may play an important role in the pathogenesis of Graves' disease.

[Antispermatogenic effects of multiglycosides of Tripterygium wilfordii and monomer T4 in the testes and epididymal spermatozoa of rats]

The antispermatogenic effects of the multiglycosides of Tripterygium wilfordii (GTW) and monomer T4 isolated from GTW on the testes and epididymal spermatozoa of rats were examined microscopically following silver staining. The dosages of GTW and T4 were 10mg/kg.d and 0.05 mg/kg.d, respectively, fed for 7 weeks via gastric intubation. Different degrees of damage to the testis and epididymal tubes were found in rats treated with GTW. Deformed, round-headed sperms and exfoliated cells (mainly spermatids and occasionally pachytene spermatocytes) were seen in the tubular lumen of the epididymis. Spermatids with deformed acrosomal vesicles were also commonly observed. No significant pathological changes were seen in other internal organs. T4 mainly caused damage to the spermatozoa in the epididymis. Under the dosage of 0.05mg/kg.d the sperm count was almost nil, but no discernible changes in the seminiferous tubules, epididymal epithelia, Leydig cells or Sertoli cells were found. The antifertility potency of T4 was 200 times stronger than that of GTW.

[A study on components and compound prescription of huangqin decoction]

The results obtained from the pharmacological experiments have preliminarily demonstrated that the compound prescription is better than its individual component drug in the range and potency of pharmacological activities. In the prescription Radix Scutellariae plays a principal role in pharmacological effects. Radix Scutellariae and Radix Paeoniae Alba can potentiate each other. Radix Glycyrrhizae and Fructus Jujubae in the compound prescription also exhibit biological activities to some extent. The relieving effect of the prescription for spasm and pain may result from the synergistic interaction between Radix Paeoniae Alba and Radix Glycyrrhiza, and the heat clearing and diarrhea stopping action is due to the biological activity of Radix Scutellariae.

[Treatment and prevention of asymmetrical intrauterine growth retardation with huoxue huayu prescription]

The purpose of this study was to observe the therapeutical and preventive effect of the compound prescriptions of Huoxue Huayu (promoting blood circulation to remove stasis, PBCRS) and Yiqi Huoxue, replenishing Qi to remove stasis, RQRS) on experimental intrauterine growth retardation (IUGR) caused by passive smoking during pregnancy in rats. The fetal average birth weight and the erythrocyte deformability were found to be significantly reduced in the smoke-exposed group compared with the control group. However, there was a significant increase of blood viscosity (at both shear rates), Hb, Ht, MCV, MCH levels and the erythrocyte fragility in the smoke-exposed group in comparison with the control group. After the mother-rats were given PBCRS and RQRS prescriptions during gestation, the fetal average birth weight and erythrocyte deformability were markedly increased. The blood viscosity, Hb, Ht, MCV, MCH levels and erythrocyte fragility of pregnant rats were decreased. No differences were found in the control group and the two treated groups. The electronic microscope observation of erythrocyte shape shows there were some protrusions on the surface of red cells in the smoke-exposed group. The protrusions were significantly reduced in the two treated groups, which was similar to the control group. The erythrocyte deformability, the blood viscosity, Hb, Ht, MCV, MCH levels indicate that there was a significant correlation between them and the fetal average birth weight respectively. This study indicates that blood stasis is one of the pathogenetic mechanisms of asymmetrical IUGR and that the PBCRS recipe could improve intrauterine growth environment of fetal which could treat and prevent IUGR in obstetrics.

[A preliminary study on the pharmacology of the compound prescription huangqin tang and its component drugs]

Results obtained from the pharmacological experiments demonstrated that the compound prescription Huangqin Tang and its component drugs, roots of Paeonia lactiflora, Scutellaria baicalensis and Glycyrrhiza uralensis, and the fruit of Ziziphus jujuba showed marked anti-inflammatory effect. The compound prescription and its component drugs, except the peony root, possessed significant antispastic effect. Antipyretic effect of Radix Scutellariae, Radix Glycyrrhizae and Huangqin Tang was suggested. Huangqin Tang, Radix Paeoniae alba, and Radix Glycyrrhizae showed marked analgesic effect. In addition, the experiments confirmed that both Huangqin Tang and single Radix Scutellariae have sedative effect.

Multipoint linkage of 9 anonymous probes to HPRT, factor 9, and fragile X

We have analyzed the segregation of restriction fragment length polymorphisms (RFLPs) associated with 9 anonymous probes detecting loci DXS10, DXS15, DXS19, DXS37, DXS51, DXS52, DXS98, DXS99, and DXS100 and probes for HPRT and F9 in a set of 40 families segregating fragile X (fra(X]. Using two-point and multipoint analysis, we have established their relative genetic locations. The results indicate that DXS99 and DXS10, unlike previous reports, are not tightly linked to F9. A new locus was found to map within the F9 - fra(X) region. DXS98 showed 6% recombination with fra(X) and appeared to be the closest locus to fra(X). These results will be useful for mapping the relative position of newly defined X probes in this region and for future genetic studies of families with fra(X), hemophilia B, or Lesch-Nyhan mutations.

Waterborne outbreak of rotavirus diarrhoea in adults in China caused by a novel rotavirus

During two epidemics of acute diarrhoea in China in late 1982/early 1983, more than 12 000 adults in two coal mining districts were affected. The virus isolated from stool samples resembled a rotavirus morphologically. Antigenically it lacked the group antigen shared by known rotaviruses. Like other rotaviruses it had a double-stranded RNA with 11 discrete segments, but the pattern of migration of the segments on polyacrylamide electrophoresis differed from those of other rotaviruses.