Development and characterization of SSR markers from Pinus massoniana and their transferability to P. elliottii, P. caribaea and P. yunnanensis

Pinus massoniana (Masson's pine) is a widespread tree species in central and southern China and northern Vietnam; it is valued for rosin and paper production. Despite the significant economic value of Masson's pine, little work has been done on its molecular genetics. We developed 318 SSR primers from genome sequences of P. massoniana, and we identified 10 polymorphic markers. The number of alleles in the population of P. massoniana that we examined ranged from two to four, and the Shannon diversity index ranged from 0.150 to 1.133. Cross-species transferability of the 318 SSRs was also analyzed in the slash pine (Pinus elliottii), the Caribbean pine (Pinus caribaea) and the Yunnan pine (Pinus yunnanensis); 15, 10, and 10 primer pairs generated polymorphic amplification, respectively. These sets of polymorphic SSR markers will be useful for population genetics studies of P. massoniana, for genetic identification of interspecific hybridization, and for phylogeographic studies of Pinus spp.

[Effect of Limax lyophilized powder on bronchial asthma]

OBJECTIVE

To study the effect of Limax lyophilized powder on bronchial asthma.

METHODS

The allergic asthma model was established in guinea pigs by combined utilization of aluminum hydroxide and egg albumin to investigate the effect of Limax lyophilized powder on the bronchial flow and on the level of inflammator in bronchoalveolar lavage and serum.

RESULTS

The mortality of asthma laboratory guinea pigs was reduced and the incubation period of asthma was extended significantly in Limax lyophilized powder groups. Its antiasthmatic effect was as efficient as the control drug (aminophylline). The leucocyte count was decreased in peripheral blood and the bronchoalveolar lavage fluid. The infiltration of pulmonary tissues eosinophil was also significantly reduced. Further more,the most efficient effects was showed in Limax lyophilized powder at the moderate dosage (63 mg/kg). The bronchial perfusion flow was increased and the level of IL-2 and IL-4 in blood serum and bronchoalveolar lavage fluid was decreased obviously in the aminophylline group and Limax lyophilized powder groups at moderate and high dosage.

CONCLUSION

Limax lyophilized powder could inhibit bronchial asthma evidently.

5-HT1-like receptors mediate contractions of the rabbit saphenous vein

5-Hydroxytryptamine (5-HT) elicited concentration-dependent contractions of the rabbit isolated saphenous vein. The effects of 5-HT were mimicked by 5-carboxamidotryptamine (5-CT), 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole succinate (RU 24969) and sumatriptan; the rank order of potency (pD2 values) was 5-CT (7.6) greater than 5-HT (6.9) greater than 8-OH-DPAT (6.2) greater than RU 24969 (6.1) greater than sumatriptan (5.7). The maximal response to RU 24969 was less than that to the other compounds, implying that RU 24969 may behave as a partial agonist. Methiothepin (10(-8), 3 x 10(-8) and 3 x 10(-7) M), ketanserin (10(-7), 3 x 10(-7) and 10(-6) M) and spiperone (10(-7), 10(-6) and 10(-5) M), but not 1 alpha H,3 alpha,5 alpha H- tropan-3-yl-3,5-dichlorobenzoate (MDL 72222; 10(-7), 10(-6) or 10(-6) M), cyanopindolol (10(-7) and 10(-6) M) or propranolol (10(-7) and 10(-6) M), shifted the concentration-effect curve of 5-HT to the right in a concentration-dependent manner with pA2 values of 8.25, 7.51 and 6.12, respectively. The high activity of 5-CT and methiothepin compared to, respectively, 5-HT and ketanserin (and spiperone) suggests that the contraction of the rabbit saphenous vein is not mediated by 5-HT2 receptors. The receptor involved seems to be mainly 5-HT1-like, similar to the one mediating contraction of the dog saphenous vein, human basilar artery and porcine cranial arteriovenous anastomoses.