蛇床子提取液的局部麻醉作用

蛇床子提取液对蟾蜍离体坐骨神经有阻滞麻醉作用;对豚鼠有浸润麻醉效果,盐酸肾上腺素可增强其麻醉强度和明显延长局麻时间;对家兔有椎管麻醉作用,但对兔眼角膜没有表面麻醉作用。蛇床子提取液的局麻作用相似于1%盐酸普鲁卡因,唯作用强度较弱、持续时间较短。此外,还能明显增强戊巴比妥钠对小鼠的催眠作用。     

Ipsilateral hemiconvulsive seizure after unilateral injection of procaine into the substantia innominata of amygdaloid-kindled rats

The effects of procaine injected into the substantia innominata (SI) and the amygdala (AM) were compared in AM-kindled rats. Intra-SI injection of procaine (ipsilateral to the kindled AM) caused immediate contralateral hemiparesis lasting for about 30 min, associated with EEG amplitude reduction. When the kindled AM was stimulated at the previously established generalized seizure triggering threshold (GST), 8/15 animals had ipsilateral hemiconvulsive seizure 5 min after the injection. In all the animals, afterdischarge was readily produced with a significant reduction in its duration. When procaine was injected into the kindled AM, there was no paresis or EEG change. AM stimulation at the GST did not evoke afterdischarge 5 min after the injection, although the kindled seizure was reactivated by a more intense stimulus. After 24 hr, all the animals, regardless of the site of procaine injection, responded to GST stimulation with a kindled seizure. The data suggest that (1) the effect of intra-SI procaine is not due to drug diffusion to the kindled AM, and (2) the kindled AM can gain access to the contralateral hemispheric motor mechanism without participation of the ipsilateral SI.     

普鲁卡因程序输注对犬的平均动脉压和心率的影响

目的 观察普鲁卡因程序输注及恒速滴注对平均动脉压（ＭＡＰ）和心率（ＨＲ）的影响。方法１２只杂种家犬随机分成两组，每组６只，体重相近，Ⅰ组１ｍｇ．ｋｇ＾－１．ｍｉｎ＾－１恒速滴入１％盐酸普鲁卡因；Ⅱ组程序输入盐酸普鲁止痼，滴注时间为７０ｍｉｎ，观测ＭＡＰ、ＨＲ。结果 普鲁卡因程序输注对家ＨＲ的影响与普鲁卡因恒速至其影响相近，普鲁卡因程序输注对ＭＡＰ的相比，只有１５ｍｉｎ点下降显著，余各占下降程度相近     

Analysis of anion conductance in frog skin

Electrophysiological characteristics of transepithelial Cl-specific conductance (g _Cl) and intracellular element concentrations were analyzed in frog skins before and during voltage perturbation to serosa +100 mV, both under control conditions and after mucosal application of procaine. Under control conditions, g _Cl was often minimal and almost insensitive to voltage perturbation. Procaine stimulated g _Cl in many cases considerably and further activation resulted then from voltage perturbation. Microelectrode determinations indicated that conductive pathways parallel to the principal cells account for the procaine-induced increase in g _Cl. The responses in g _Cl were not related to the density of mitochondria-rich (MR) cells. Electron microprobe analysis of intracellular electrolyte concentrations showed that procaine increased the Cl content of MR cells significantly. Gain of Cl was primarily due to uptake across the basolateral membrane, as indicated by the small accumulation of Br after unilateral mucosal application. Voltage perturbation to serosa + 100 mV in the presence of Br on the mucosal side led in procaine-stimulated tissues to an increase of the ratio of Br/Cl content in the majority of MR cells. It was much less than predicted for conductive transcellular anion transport. Also, intracellular Cl concentrations of MR cells were far above those expected for a highly Cl-permeable basolateral membrane. The data, although indicating finite Cl/Br transport across MR cells, are incompatible with the idea that the voltage-activated conductive Cl transport occurs though these cells. Alternatively, we suggest passage across highly Clspecific sites of a paracellular pathway.     

Behavioral pharmacology of local anesthetics: Reinforcing and discriminative stimulus effects

The reinforcing properties of several short-acting esteratic local anesthetics were determined in rhesus monkeys experienced in the IV self-administration of cocaine. In addition, the discriminative stimulus properties of these and several other local anesthetics of both the ester and amide class were determined in rats trained to discriminate procaine from saline in a 2-lever operant task. IV delivery of chloroprocaine, dimethylprocaine or dimethocaine maintained responding above vehicle levels in most monkeys while propoxycaine, piperocaine and dimethylaminoethanol (Deanol) failed to maintain self-administration behavior. Thus some, but not all, short-acting esteratic local anesthetics are positive reinforcers in rhesus monkeys. In addition, it is unlikely that the reinforcing effects of dimethylprocaine are mediated by its metabolite dimethylaminoethanol. In rats, all local anesthetics tested except piperocaine and procainamide resulted in responding on the procaine-appropriate lever indicating procaine-like discriminative stimulus effects for these compounds. In addition, injections of d-amphetamine resulted in principally procaine lever responding. All local anesthetics that were self-administered by rhesus monkeys had discriminative stimulus effects in rats that were similar to those of procaine. However, not all local anesthetics that were procaine-like in rats were self-administered by rhesus monkeys. These data may represent a separation of these two stimulus properties for local anesthetics although other variables such as species differences may play a role.     

Mobilization of stored calcium for phasic contraction induced by norepinephrine in rabbit aorta.

In Ca-free solution norepinephrine (NE) produced only a phasic contraction in the media-intima layer of rabbit aorta. The second application of NE was almost ineffective. Incubation of the muscle with Ca for a short period (Ca loading) restored the ability to produce a phasic contraction in Ca-free solution. Various ions and compounds were applied to the muscle prior to the Ca loading or prior to NE application and it was found that these treatments variously affected the NE-induced phasic contraction. The data suggest that the NE-induced phasic contraction in Ca-free solution results from Ca release from cellular sites and that a hyperbolic relationship exists between the amount of Ca at these sites and the magnitude of the contraction. These sites take up extracellular Ca by a process sensitive to La3+ but not to D600; the Ca influx stimulated by high K solution, which is sensitive to D600 and also contributes to refilling of these sites; NE releases this stored Ca by a process sensitive to procaine, caffeine and theophylline and, in this manner, elicits a phasic contraction.     

普鲁卡因对离体人红细胞膜ATPases活性的影响

盐酸普鲁卡因是静脉复合麻醉（ＩＢＡ）的常用药物之一。我们发现在ＩＰＢＡ下施行上腹部手 术时，术毕人红细胞膜ＡＴＰａｓｅｓ活性有所下降。本研究的目的是观察普鲁卡因对离体人红细胞膜ＡＴ－ Ｐａｓｅ活性是否有直接影响。结果；一定浓度的普鲁卡因对Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性有明显抑制作用，对 Ｍｇ２＋－ＡＴＰａｓｅ活性无明显作用，对Ｃａ２＋－Ｍｇ２＋－ＡＴＰａｓｅ活性有轻微保护作用。研究结果为临床合理应 用ＩＰＢＡ提供了一定的实验依据。     

Differential effects of phenylbutazone and local anesthetics on nociception in the equine

The effects of procaine, mepivacaine and phenylbutazone on pain perception in the equine were studied using two behavioral assays of nociception; the thermal evoked hoof withdrawal reflex and skin twitch reflex. Pain perception threshold was measured as the latency from onset of thermal stimuli to reflex withdrawal of the forelimb or contraction of the cutaneous musculature. Procaine 2% and mepivacaine 2% prolonged the hoof withdrawal reflex latency when administered locally by producing a block of the palmar and metacarpal nerves. Significant analgesia lasted 90 min and 210 min for procaine and mepivacaine, respectively. Phenylbutazone (7.3 mg/kg) failed to alter pain thresholds measured over a 36 h post-treatment period. However, pain thresholds rose over time with successive trials. These data suggest that in the equine (1) phenylbutazone does not alter normal cutaneous pain perception, and (2) successive presentation of painful stimuli increases nociceptive thresholds.     

Conformational aspects of the antifibrillatory activity of procaine

The effects of procaine and foursemi-rigid conformational analogs (compounds 1, 2, 3 and 4) were tested and compared on isolated rabbit atria. Procaine and the four analogs produced positive inotropic effects at all dose levels tested.

The antifibrillatory activity of procaine and its analogs arranges in decreasing order of activity was compound 4 > 3 > 2 > 1 procaine. The antifibrillatory activity of the compounds correlated to the distance between the ring nitrogen and the ester oxygen; that is, as the N-O distance increased the concentration required to reduce the following frequency decreased. However, the compound became more toxic as the N-O distance increased. Our data do not confirm the commonly regarded direct relationship between local anesthetic activity and antifibrillatory activity of procaine. Differences in activity displayed by the isomers of procaine could reflect differences in the ability of these analogs to bind to receptors responsible for the respective actions.     

PURGING OF ACUTE NON-LYMPHOCYTIC LEUKEMIA PROGENITORS BY PROCAINE AND HYPERTHERMIA

Procaine and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemlc cells. In this study, the combined effects of procaine and hyperthermia on the growth of hematopoietic progenitors (GM-CFU) and ieukemic progenitors (L-CFU) were examined to determine if this combination resulted in a great selective killing of leukemlc cells than that achieved by procaine or heat alone. When the cells were treated simutaneously with procaine (2 mM) and hyperthermia (42℃) for one hour, the killing of L-CFU was enhanced considerably whereas GM-CFU were not markedly affected. These data Indicate that the combined treatment with procain and hyperthermia might offer an efficient mean to selectively purge residual leukemlc cells in vitro. Procaine with hyperthermia may have a role in clinical autoiogous bone marrow transplantation for acute leukemia.