Conducting pathways of the rabbit lumbar sympathetic ganglia

Conducting pathways of ganglia from the lumbar portion (L₃–L₅) of the sympathetic trunk in rabbits were studied by recording action potentials from nerves of the ganglia evoked by stimulation of other nerves of these ganglia, and by intracellular recording from single neurons. Besides the well-known system of descending preganglionic fibers, which enter the trunk through white rami communicantes and, as they pass through the ganglia, form synapses on ganglionic neurons, some preganglionic fibers were shown to enter the sympathetic chain through gray rami communicantes and to run in both ascending and descending directions, forming synaptic connections with neurons of the lumbar ganglia.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 16, No. 2, pp. 247–254, March–April, 1984.     

小鼠BW5147细胞与网织红细胞融合后cAMP水平及其磷酸二酯酶的细胞化学观察

本实验用PEG介导,将小鼠BW_(5147)细胞与小鼠网织红细胞在体外进行悬浮融合,经HAT选择性培养基筛选获得的胞质杂交细胞,表现出增殖减慢、生长率下降、生瘤能力降低等去恶化现象。本实验从cAMP-PDE细胞化学反应显示出胞质杂交细胞内cAMP-PDE活性比亲本BW_(5147)瘤细胞有所减弱,而cAMP水平则有所升高,提示胞质杂交细胞恶性程度下降可能与细胞内cAMP-PDE活性降低和cAMP水平升高具有一定的关系。本实验的结果将为进一步探索促使肿瘤细胞逆转的可能途径提供一定的依据。     

社鼠一新亚种——闹牛社鼠

社鼠是鼠科的一种,我国已记载的有六种。作者在吉林西部闹牛山采得一新亚种,其尾短,尾长率小于1,与已知各亚种不同,定名为社鼠闹牛亚种(Rattus nivienter naoniuensis,subsp.nov)。     

横断山蝗虫二新属二新种

在整理横断山综合考察队所采集的部分蝗虫标本时发现二新属。 模式标本存放在中国科学院动物研究所。 珂蝗属 Anepipodisma新属 体形中等大小,具粗刻点。头短于前胸背板。头顶低凹,侧隆线明显。复眼间头顶的宽度大于触角间颜面隆起的宽。颜面略倾斜,颜面隆起几乎全长明显,具纵沟,此纵沟向上延伸至头顶的端部,形成凹口(图1)。复眼长卵形。触角细长,到达或超过前胸背板的     

家白蚁的生物学和群体发育

家白蚁Coptotermes formosanus Shiraki的生物学和初建群体的经过,显示有如下特性:(1)在广州室温条件下,成虫配对后5至10天开始产卵,产卵盛期集中在6天至7天。当年产卵期有5个月,每头雌虫平均产卵约为46粒。雌里产卵后,如果不断将卵取走,产卵量显著提高。这时,每头雌虫平均可产卵约96粒。(2)家白蚁卵要经过成虫或工蚁用口舐触和搬动卵粒才能孵化。孵化期在室温下为31至35天,32至33天为孵化高峰期。卵的孵化期随温度而变化。(3)初步测定幼蚁共有6个龄期。1—2龄幼蚁不活跃,要靠成虫或工蚁喂养,3龄后幼蚁非常活跃并能自己取食。4龄期间出现工蚁和兵蚁的分化,拟工蚁可以产生短翅补充型。(4)蚁巢成片叶状,由成虫唾液与食物及沙土等基质组成。配对后80天腔室内开始出现巢架。(5)家白蚁生活史漫长,需8年才能完成一个周期。     

Interaction of peanut agglutinin,a lectin specific for nonreducing terminal d-galactosyl residues,with embryonal carcinoma cells

Peanut agglutinin (PNA), a lectin specific for terminal d-galactosyl residues, was found to react with embryonal carcinoma cells, but not with their differentiated derivatives. Receptors for PNA were detectable at the surface of all cells of the quasinullipotent F9 line and on only 50% of the multipotent PCC3/A/1 line. The fraction of the PCC3/A/1 population which expresses the F9 antigen was found to be included in the subpopulation carrying the PNA receptors. PNA⁺ and PNA^? subpopulations of PCC3/A/1 were separated by a PNA-mediated reversible agglutination of PNA⁺ cells with rabbit erythrocytes. These subpopulations were essentially F9⁺ and F9^?, respectively.     

Selectivity of edta-modified calcium channels to monovalent cations

The characteristics of slow inward sodium currents arising in response to membrane depolarization were studied in experiments on isolated dialyzed neurons of the snailHelix pomatia when the calcium-chelating agent EDTA was added to the calcium-free external solution. Values of the relative permeability of the corresponding ionic channels, determined from the shift of the equilibrium potential, were: P_Na+:P_Li+: +=1.00:0.80:0.55:0.21. The ratio between these values for "fast" sodium channels was 1.00:1.04:0.44:0.19. The induced sodium current was blocked by D-600 and nifedipine, which block calcium channels, more effectively than the calcium current of the same membrane (the corresponding dissociation constants were 10^–5 and 0.8·10^–5 mole/liter for the induced sodium current compared with 2.6·10^–5 and 2.3·10^–5 mole/liter for the calcium current). It is postulated on the basis of these data that the calcium channels have a principal selective filter similar to that of sodium channels, but also an additional binding site for bivalent cations, which prevents entry of monovalent cations into the channel. The addition of calcium-chelating agents to the calcium-free external solution liberates this site and thereby modifies the calcium channel into a sodium channel.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 14, No. 5, pp. 491–498, September–October, 1982.