青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究

将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5～4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。     

Study of the duration of antimicrobial chemotherapy in mycoplasmal pneumonia]

We assessed the period of administration of antibiotics required for cases of mycoplasmal pneumonia. The subjects were 38 patients with mycoplasmal pneumonia admitted to our hospital. These patients were treated with 100 mg minocycline or 500 mg erythromycin by intravenous infusion twice a day. They were divided into a 6 day-administration group (Group A; 16 cases) and a 9 day-administration group (Group B; 17 cases). Administration was discontinued on the 4th day or earlier in 5 cases due to side effects. A comparative assessment was made between Groups A and B with respect to body temperature, WBC, erythrocyte sedimentation rate, CRP, and chest X-ray on the 3rd, 6th, and 9th days of treatment, but no significant difference was observed. Residual shadows at the end of treatment were present in 100% of Group A and in 47% of Group B, but they disappeared gradually in both groups. No cases of recurrence were observed in either Group A or B within 1 month after the completion of treatment. Regarding the treatment period for mycoplasmal pneumonia by intravenous infusion of minocycline or erythromycin, no significant clinical difference was observed between the 6 day-administration group and the 9 day-administration group, suggesting that 6 days of administration is sufficient for treatment.     

Chemosensitivity of neurons in the dorsal motor nucleus of the vagus that responded to portal infusion of hypertonic saline in rats

Neural responses in the dorsal motor nucleus of the vagus (DMV) to topical administrations of sodium and portal infusions of hypertonic saline were investigated electrophysiologically by using multibarrel electrodes in anesthetized rats. Of 102 neurons that showed antidromic response to electrical stimulation of the ventral gastric vagus or the accessory celiac vagus, 51 neurons increased and 13 neurons decreased their discharge rates in response to the electrophoretic administration of sodium. The other 38 neurons did not respond to this stimulation. The portal infusion of hypertonic saline elicited neural responses of some DMV neurons whose axons are involved into either the ventral gastric or the accessory celiac vagus. Further, effects of the topical administration and the portal infusion of hypertonic saline were examined on 33 neurons. Typical response was characterized by an increase in discharge rate responding to both of the portal infusion and the topical administration. In conclusion, the DMV neurons receiving the afferent inputs from hepatoportal osmoreceptors may have an enteroceptor function detecting the change in osmotic pressure of their environment.     

Effect of portal infusion of hypertonic saline on neurons in the dorsal motor nucleus of the vagus in the rat

Effects of hepatoportal osmo-receptive (or sodium-receptive) afferents on neurons within the dorsal motor nucleus of the vagus (DMV) were investigated electrophysiologically in urethane-chloralose anesthetized rats. Responses of 56 spontaneously active neurons to antidromic stimulation of the ventral trunk of the subdiaphragmatic vagus were recorded in the left DMV. Among them, 35 neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve (inhibitory neurons), except two neurons that were slightly excited. Effects of portal infusion of 3.6% NaCl were examined on 26 inhibitory neurons. Sixteen neurons increased their discharge rates and one neuron decreased its discharge rate in response to portal infusion of hypertonic saline. Thirty-five DMV neurons responded to electrical stimulation of the dorsal trunk of the subdiaphragmatic vagus were inhibited by electrical stimulation of the hepatic branch of the vagus. Four neurons were excited by this stimulation. Relatively smaller number of neurons (5 out of 22 inhibitory neurons) increased their discharge rates in response to portal infusion of hypertonic saline. In conclusion, the response of DMV neuron observed in this experiment was characterized by increasing the frequency of spike discharges in response to portal infusion of hypertonic saline. However, these neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve. These results suggest that the hepatoportal osmoreceptive afferents may be conveyed to the DMV via inhibitory synapses.