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The present study was designed to investigate brain stem responses to manual acupuncture (MA) and electroacupuncture (EA) at different frequencies at pericardial P (5-6) acupoints located over the median nerve. Activity of premotor sympathetic cardiovascular neurons in the rostral ventral lateral medulla (rVLM) was recorded during stimulation of visceral and somatic afferents in ventilated anesthetized rats. We stimulated either the splanchnic nerve at 2 Hz (0.1-0.4 mA, 0.5 ms) or the median nerve for 30 s at 2, 10, 20, 40, or 100 Hz using EA (0.3-0.5 mA, 0.5 ms) or at approximately 2 Hz with MA. Twelve of 18 cells responsive to splanchnic and median nerve stimulation could be antidromically driven from the intermediolateral columns of the thoracic spinal cord, T2-T4, indicating that they were premotor sympathetic neurons. All 18 neurons received baroreceptor input, providing evidence of their cardiovascular sympathoexcitatory function. Evoked responses during stimulation of the splanchnic nerve were inhibited by 49 +/- 6% (n = 7) with EA and by 46 +/- 4% (n = 6) with MA, indicating that the extent of inhibitory effects of the two modalities were similar. Inhibition lasted for 20 min after termination of EA or MA. Cardiovascular premotor rVLM neurons responded to 2-Hz electrical stimulation at P 5-6 and to a lesser extent to 10-, 20-, 40-, and 100-Hz stimulation (53 +/- 10, 16 +/- 2, 8 +/- 2, 2 +/- 1, and 0 +/- 0 impulses/30 stimulations, n = 7). These results indicate that rVLM premotor sympathetic cardiovascular neurons that receive convergent input from the splanchnic and median nerves during low-frequency EA and MA are inhibited similarly for prolonged periods by low-frequency MA and EA.

The interaction between the p orbit of the auxochrome, the maximum bonding orbit (pi) and the minimum antibonding orbit (pi*) of the chromophore forms three new molecular orbit, among which the antibonding orbit (pi*') has the highest energy that is higher than those of the original pi*. The maximum occupied orbit (pi') will have energy lower or higher than those of pi according to different auxochrome and chromophore, and the energy of n orbit will remain steady, because the n orbit of the original chromophore is perpendicular to the p orbit of the auxochrome and the interaction is negligeable. As a result, the absorption wavelength of transition n-->pi* will shift towards higher photon energy, but for transition pi-->pi*, the absorption wavelength will shift towards either lower or higher photon energy, depending on the species of auxochrome and chromophore.

This paper discusses the effect mechanism of auxochrome of electronic spectrum. The study proves that the auxochrome does not invariably make the maximum absorption wavelength of chromophore shift towards lower photon energy. For the transition of n-->pi*, the p orbit of the auxochrome interacts with the minimum antibonding empty orbit(pi*), which will make the energy of pi* increase, while the p orbit of the auxochrome is perpendicular to the n orbit of chromophore, and the energy of the n orbit will remain steady ultimately, so the transition energy of n-->pi* will increase. For the transition of pi-->pi*, the interaction of p orbit of the auxochrome and maximum bonding orbit (pi) of the chromophore forms new orbits, so the energy of the maximum bonding orbit in new orbits will increase. In some compounds, the increase is higher than those of pi*, so the transition energy of pi-->pi* will decrease and absorption wavelength will shift towards lower photon energy, which, however, is reverse in other compounds.