Effect of physostigmine and scopolamine on the memory functions of chess players

Six young trained chess players received 10 consecutive tasks comprising problematic play position at chess. Each subject was tested four times with drug orders balanced across subjects. Compared with saline placebo, physostigmine (20 microgram/kg i.v.) in the presence of peripheral muscarinic blockade (methylscopolamine 6 microgram/kg i.v.) impaired the performance of good players, but the amount of correct solutions was increased when the initial performance level was low. Scopolamine (6 microgram/kg i.v.) impaired the performance of all subjects, and saline placebo proved inactive. The effect of scopolamine together with physostigmine was about the average of the separate effects of these drugs. The subjects talked less, when mildly sedated, and felt nauseated after the physostigmine treatment. Antimuscarinics with and without physostigmine caused cycloplegia in all subjects.     

Muscarinic supersensitivity of anterior pituitary ACTH and B-endorphin release in major depressive illness

Subjects with major depressive illness had greater increases in plasma concentrations of ACTH and B-endorphin immunoreactivity in response to central muscarinic stimulation by physostigmine, than did normal control subjects, or psychiatric control subjects without major depressive illness. These findings provide further evidence for muscarinic receptor supersensitivity in depression and may implicate an abnormality of peptide physiology in the pathogenesis of depression.     

Effects of the infusion of glucagon on the blood levels of thyroid hormones

We have attempted to determine if mild hyperglucagonemia induced by exogenous glucagon infusion induces changes of serum thyroid hormone levels. Eleven healthy subjects, overnight fasting, received glucagon infusion (2 mg/90 min i.v.), whereas 5 healthy subjects (control group) received normal saline infusion. In the subjects infused with exogenous glucagon plasma glucagon concentrations increased from 130 +/- 24 pg/ml to 550 +/- 68 pg/ml at the end of infusion. At the same time no significant changes in serum T3, rT3 and T4 levels were found. A significant increase in serum rT3 levels was found 270 min after glucagon infusion withdrawal, whereas serum T4 levels remained unaltered during the whole period. Normal saline infusion failed to induce any variation in control group, however a late (at 6th hour) mild increase of serum rT3 in these subjects resulted comparable to the same increase of glucagon infused subjects. The results from this study suggest that mild increase in plasma glucagonemia, as found in patients with severe illness, does not induce a short-time significant lowering of serum T3 and a simultaneous rise of serum rT3 in normal subjects.     

L-arginine protects from ischemia-reperfusion-induced endothelial dysfunction in humans in vivo.

It has been shown that nitric oxide (NO) protects from myocardial ischemia-reperfusion injury in animal models. The present study investigated whether administration of the NO substrate l-arginine protects against ischemia-reperfusion-induced endothelial dysfunction in humans. Forearm blood flow was measured with venous occlusion plethysmography in 16 healthy male subjects who were investigated on two occasions. Forearm ischemia was induced for 20 min followed by 60-min reperfusion. With the use of a crossover protocol, the subject received a 15-min intrabrachial artery infusion of l-arginine (20 mg/min) and vehicle (saline, n = 12 or d-arginine, n = 4) starting at 15 min of ischemia on two separate occasions. Compared with preischemia, endothelium-dependent increase in forearm blood flow induced by intra-arterial acetylcholine (3-30 microg/min) was significantly impaired at 15 and 30 min of reperfusion when the subjects received saline (P < 0.001). When the subjects received l-arginine, the acetylcholine-induced increase in forearm blood flow was not significantly affected by ischemia-reperfusion. The recovery of endothelium-dependent vasodilatation at 15- and 30-min reperfusion was significantly greater after administration of l-arginine than after saline (P < 0.05). d-Arginine did not affect the response to acetylcholine. Endothelium-independent vasodilatation to nitroprusside was not affected during reperfusion. These results demonstrate that the NO substrate l-arginine significantly attenuates ischemia-reperfusion-induced endothelial dysfunction in humans in vivo. This suggests that l-arginine may be useful as a therapeutic agent in the treatment of ischemia-reperfusion injury in humans.     

腹腔注射四氯化碳辅以饮食改良制备犬慢性肝纤维化模型

探讨一种经典的、与人类慢性肝纤维化——肝硬化进程相似的大动物模型建立方法.采用15只成年健康中华田园犬:对照组5只,使用生理盐水腹腔注射及正常饲料干预;实验组10只,采用小剂量四氯化碳(CCl4)腹腔注射及高脂饮食干预.间断采血检测肝功能、血清学肝纤维化指标,B超引导下定期肝穿活检作HE染色和Masson染色.56周后所有实验动物成功诱导至不同程度的肝纤维化.丙氨酸氨基转移酶、门冬氨酸转氨酶、球蛋白、总胆红素、γ-谷氨酰基转肽酶以及透明质酸与对照组相比,差异均有统计学意义(P<0.05).联合应用小剂量CCl4和单纯高脂饮食可成功诱导犬慢性肝纤维化-肝硬化模型,该方法动物存活率和成模率均较高,可为后续的相关研究提供更好的平台.     

Hemodynamic effects of lipids in humans

Evidence suggests lipid abnormalities may contribute to elevated blood pressure, increased vascular resistance, and reduced arterial compliance among insulin-resistant subjects. In a study of 11 normal volunteers undergoing 4-h-long infusions of Intralipid and heparin to raise plasma nonesterified fatty acids (NEFAs), we observed increases of blood pressure. In contrast, blood pressure did not change in these same volunteers during a 4-h infusion of saline and heparin. To better characterize the hemodynamic responses to Intralipid and heparin, another group of 21 individuals, including both lean and obese volunteers, was studied after 3 wk on a controlled diet with 180 mmol sodium/day. Two and four hours after starting the infusions, plasma NEFAs increased by 134 and 111% in those receiving Intralipid and heparin, P < 0.01, whereas plasma NEFAs did not change in the first group of normal volunteers who received saline and heparin. The hemodynamic changes in lean and obese subjects in the second study were similar, and the results were combined. The infusion of Intralipid and heparin induced a significant increase in systolic (13.5 +/- 2.1 mmHg) and diastolic (8.0 +/- 1.5 mmHg) blood pressure as well as heart rate (9.4 +/- 1.4 beats/min). Small and large artery compliance decreased, and systemic vascular resistance rose. These data raise the possibility that lipid abnormalities associated with insulin resistance contribute to the elevated blood pressure and heart rate as well as the reduced vascular compliance observed in subjects with the cardiovascular risk factor cluster.     

Cholinergic agents: antinociception without morphine type dependence in rats

We have confirmed the work of others showing that loss in body weight is a predictable and consistent sign of opiate withdrawal in rats. Rats that were treated chronically with either oxotremorine or physostigmine displayed no weight loss or other signs of opiate-like withdrawal when the drugs were withdrawn. Furthermore, there was no difference in weight loss between morphine dependent rats substituted with saline and those substituted with either cholinergic drug. However, we did observe an increased mortality among rats substituted with a cholinergic agent compared with saline. Rats infused with a mixture of morphine plus oxotremorine or morphine plus physostigmine showed less weight loss, but not fewer behavioral signs, after the end of the infusion than rats treated only with morphine. It is concluded that the cholinergic agents did not cause a morphine-like physical dependence themselves, but appeared to antagonize to some extent the development or manifestation of opiate dependence.     

Effect of atropine and/or physostigmine on cerebral acetylcholine in rats poisoned with Soman

Cerebral acetylcholine (ACh) levels in normal animals were found to be 29.6 ± 1.4 (S.E.) nmoles ACh/g of wet tissue. Physostigmine and Soman reduced cerebral cholinesterase (ChE) activity to < 18% of control and increased cerebral ACh levels by 148 and 130% of normal, respectively. Neostigmine failed to alter ChE activity or ACh levels. Atropine decreased ACh levels to 62% of normal. When atropine was given with physostigmine or Soman, the ACh levels were almost normal. Soman failed to increase the levels of ACh in animals protected with atropine and physostigmine. When physostigmine was followed by Soman, cerebral ACh levels were lower than in animals given physostigmine only.Our data indicate that it may be possible to manage ACh concentrations in animals poisoned with irreversible ChE inhibitors by prior treatment with apprópriate dosages of anticholinergic and reversible anti-ChE drugs. The data also suggest that ACh and/or anti-ChEs inhibit the synthesis of ACh.     

Zinc acutely and temporarily inhibits adrenal cortisol secretion in humans

Hypo- and hyperzincemia has been reported to cause alterations in the adrenal secretion. To determine the acute effect of zinc on cortisol levels, we studied 27 normal individuals of both sexes aged 20-27 y after a 12-h fast. The tests were initiated at 7:00 AM when an antecubital vein was punctured and a device for infusion was installed and maintained with physiological saline. Zinc was administered orally at 8:00 AM. Subjects were divided into an experimental group of 13 individuals who received doses of 25, 37.5, and 50 mg of zinc and a control group of 14 individual who received 20 mL of physiological saline. Serial blood samples were collected over a period of 240 min after basal samples (-30 and 0 min). We detected an acute inhibitory effect of zinc on cortisol secretion during 240 min of the study period in the experimental group.     

Plasma leptin suppression by arginine vasopressin in normal women and men

Leptin inhibits appetite by activating several neuroendocrine systems, including the hypothalamo-pituitary-adrenal cortical (HPA) axis. In turn, elevated glucocorticoids can increase circulating leptin. We therefore measured plasma leptin in 12 normal women and eight normal men administered low-dose physostigmine (PHYSO) and arginine vasopressin (AVP) to stimulate the HPA axis. The subjects underwent four test sessions 5-7 days apart: PHYSO (8 microg/kg IV), AVP (0.08 U/kg IM), PHYSO + AVP, and saline control. Serial blood samples were taken before and after pharmacologic challenge and analyzed for leptin, adrenocorticotropin (ACTH)1-39, cortisol, and AVP. Estradiol and testosterone also were measured at each test session. PHYSO and AVP produced no side effects in about half the subjects and predominantly mild side effects in the other half, with no significant female-male differences. Correlations between side effects (absent or present) after PHYSO or AVP and the corresponding leptin responses were nonsignificant. Baseline plasma leptin concentrations were significantly higher in the women than in the men (p < 0.003). Leptin concentrations following PHYSO remained unchanged from baseline, indicating that the short-lived ACTH and cortisol increases produced by PHYSO did not affect leptin secretion. In contrast, AVP administration, while also increasing ACTH and cortisol, suppressed leptin, to a significantly greater degree in the women than in the men (p = 0.01). This significant suppression of leptin by AVP has not been previously described; physiologically, it may be part of a negative feedback regulatory system between central leptin and its activation of the HPA axis, by inhibition of leptin production or acceleration of its clearance.     

Physostigmine effects in Alzheimer's disease: relationship to dementia severity

Eleven demented patients were administered .004, .009, and .013 mg/kg physostigmine intramuscularly, and placebo, double-blind, in Phase 1. The most effective dose, in terms of showing the best memory score as compared to saline, was repeated during Phase 2. Five patients improved their verbal memory scores in both Phases 1 and 2 after the most effective dose of physostigmine; these five "responders" were found to be significantly more demented than the six "nonresponders." Drug-induced increases in memory scores were significantly correlated with illness severity. Intrusions, which were not a factor in selection of the most effective dose, were reduced in the group as a whole, with the responders showing the most improvement and the nonresponders the least. The association between physostigmine effect and degree of dementia suggests to us that the severe cases may have more permeable blood-brain barriers, and that drug availability to the brain is an important factor in evaluating treatment of SDAT with cholinergic substances.     

Comparative effect of galanin and pyridostigmine on the growth hormone response to growth hormone-releasing hormone in normal aged subjects.

The aim of our study was to investigate the effects of aging on the growth hormone (GH) response to growth hormone-releasing hormone (GHRH) alone and in combination with either the neuropeptide galanin or the acetylcholinesterase inhibitor pyridostigmine (PD) in normal subjects. In protocol 1 (GHRH/galanin), 9 old healthy volunteers, ranging in age from 68 to 97 years, and 6 young subjects, ranging in age from 25 to 31 years, received: (a) human GHRH (1-29)NH2, 100 micrograms in 1 ml saline, as an intravenous bolus, and (b) porcine galanin, 500 micrograms in 100 ml saline, as an intravenous infusion from -10 to 30 min combined with GHRH, 100 micrograms i.v. at time 0. In protocol 2 (GHRH/PD), 14 old healthy volunteers, ranging in age from 65 to 91 years, and 11 young subjects, ranging in age from 19 to 34 years, received: (a) GHRH (1-29)NH2, 100 micrograms in 1 ml saline, as an intravenous bolus, and (b) PD, 120 mg administered per os 60 min before GHRH, 100 micrograms as an intravenous bolus. Blood samples for GH were drawn at -75, -60 (time of PD administration), -45, -30, -15, -10 (time of beginning of galanin infusion), 0 (time of GHRH injection), 15, 30, 45, 60, 90, and 120 min. The GH response to GHRH was significantly (< 0.05) enhanced either by galanin or PD pretreatment both in young and old subjects. However, the GH response to GHRH alone or combined with either galanin or PD was significantly greater in the young subjects as compared to the old subjects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Neonatal administrations of a vasopressin analog (DDAVP) and hypertonic saline enhance learning behavior in rats

Groups of newborn Wistar rats received daily 1-desamino-8-D-arginine-vasopressin (DDAVP), oxytocin (OXT), hypertonic saline or normal saline for 14 days from day 1 to day 14 of life. One or three months later they were trained in a maze for brightness discrimination (BD). A group of untreated adult male rats received posttrial DDAVP or normal saline for brightness discrimination. Subsequently all the retentions of BD were tested after one month. We found that the neonatal treatments with both DDAVP and hypertonic saline facilitated acquisition and subsequent maintenance of brightness discrimination in immature and mature rats, and also that posttreatment with DDAVP enhanced retention of BD in adult rats. Oxytocin and normal saline had no effect on these parameters. The results are interpreted as showing that endogenous AVP and its synthetic analog enhance the development and adult function of central neural substrates involved in learning behaviors.     

Galvanic vestibular stimulation improves the results of vestibular rehabilitation

Here, we present findings from a three-step investigation of the effect of galvanic vestibular stimulation (GVS) in normal subjects and in subjects undergoing vestibular rehabilitation (VR). In an initial study, we examined the body sway of 10 normal subjects after one minute of 2 mA GVS. The effect of the stimulation lasted for at least 20 minutes in all subjects and up to two hours in 70% of the subjects. We then compared a group of patients who received conventional VR (40 patients) with a group that received a combination of VR and GVS. Results suggest a significant improvement in the second group. Finally, we attempted to establish the optimal number of GVS sessions and to rule out a placebo effect. Fifteen patients received "systematic" GVS: five sessions, once a week. Five patients received "nonsystematic" galvanic stimulation in a sham protocol, which included two stimulations of the clavicle. These data were analyzed with Fisher's exact test and indicated that the best results were obtained after three sessions of GVS and no placebo effect was observed.     

Procaine (Novocain) Treatment of Patients with Senile and Arteriosclerotic Brain Disease

Of 32 patients (13 men and 19 women) with a mean age of 81.1 years committed to a mental hospital for senile or arteriosclerotic psychoses, 11 received 2% procaine hydrochloride according to Aslan''s method, for an average of 13 months, 11 for 6 months, and 10 normal saline. Of 20 patients, with a mean age of 72 years, who attended the geriatric psychiatric clinic of a general hospital, 10 were treated with procaine hydrochloride and 10 with normal saline for six months. Procaine hydrochloride applied for six or 12 months did not appreciably alter the symptomatology and course of senile and arteriosclerotic brain disease. It did not improve the senile amnestic syndrome or neurological symptomatology, when present. The general mood and level of activity improved temporarily. It was also temporarily helpful in alleviating depressive symptoms in patients suffering from arteriosclerotic brain disease.     

Limb venous distension evokes sympathetic activation via stimulation of the limb afferents in humans

We have recently shown that a saline infusion in the veins of an arterially occluded human forearm evokes a systemic response with increases in muscle sympathetic nerve activity (MSNA) and blood pressure. In this report, we examined whether this response was a reflex that was due to venous distension. Blood pressure (Finometer), heart rate, and MSNA (microneurography) were assessed in 14 young healthy subjects. In the saline trial (n = 14), 5% forearm volume normal saline was infused in an arterially occluded arm. To block afferents in the limb, 90 mg of lidocaine were added to the same volume of saline in six subjects during a separate visit. To examine whether interstitial perfusion of normal saline alone induced the responses, the same volume of albumin solution (5% concentration) was infused in 11 subjects in separate studies. Lidocaine abolished the MSNA and blood pressure responses seen with saline infusion. Moreover, compared with the saline infusion, an albumin infusion induced a larger (MSNA: Δ14.3 ± 2.7 vs. Δ8.5 ± 1.3 bursts/min, P < 0.01) and more sustained MSNA and blood pressure responses. These data suggest that venous distension activates afferent nerves and evokes a powerful systemic sympathoexcitatory reflex. We posit that the venous distension plays an important role in evoking the autonomic adjustments seen with postural stress in human subjects.     

The effects of TRH on prolactin, plasma renin activity, water and electrolyte excretion in normal males.

The effect of TRH induced secretion of TSH and prolactin (hPrl) on plasma renin activity (PRA), water and electrolyte excretion, was studied in 7 normal males before and after an intravenous injection of 2 ml normal saline or 200 microgram TRH. Plasma hPrl and TSH rose significantly (p less than 0.01) in all 7 subjects after TRH but not after saline injection. No significant differences in the hourly excretion of sodium, potassium and free water clearance were noted before and after either saline or TRH injection. Mean PRA values of the 7 subjects were similar after either the 2 ml saline of TRH injection. Our results indicate that despite a correlation between basal hPrl and sodium excretion as well as free water clearance, acute TRH induced elevation of hPrl is not associated with changes of urinary sodium and potassium excretion, free water clearance and PRA in normal males. These findings provide some evidence against a direct osmoregulatory role of hPrl in man.     

The physostigmine depolarization potentiating effect of salicylate in frog skeletal muscle.

1) The frog's sartorius muscle was depolarized depending on the degree of concentration 2--4 times more intensely by physostigmine salicylate than by physostigmine sulphate. 2) In normal Ringer's solution, 1 mM physostigmine salicylate decreased the sensitivity of the membrane to potassium depolarization by about 90%. Under similar experimental conditions, physostigmine sulphate and Na salicylate, respectively, decrease the sensitivity of the membrane to potassium depolarization by about 30%. 3) The difference manifested in the depolarizing effect of salicylate and other physostigmine salts (chloride, sulphate, phosphate, formiate, acetate, monochloracetate, benzoate and para-oxy-benzoate) is expressed already at 1 mM concentration (about 10-fold), if the muscle had been equilibrated in chloride-free glucuronate or sulphate milieu. 4) The depolarization develops slowly. It takes 30--60 minutes for the new steady state to develop even in the superficial sartorius fibres. If depolarization has reached its maximum on an average 100 mV, the membrane potential remains unchanged for hours. 5) Depolarization ensues at an unchanged degree in the presence of Na-free (choline) Ringer as well as in the presence of 2X10(-8) g/ml tetrodotoxin; therefore, it is not a Na-dependent process. 6) Under the influence of 1 mM physostigmine salicylate the membrane's resistance to the inward potassium current increased about twofold, while the increase was only 15% to the outward potassium current. It is assumed that the salicylate anion is characteristically capable of potentiating the decreasing effect of physostigmine on potassium permeability, though the role of the metabolic effect of salicylate cannot be excluded.     

葡激酶突变体对高脂喂养大鼠血液常规指标的影响

目的研究葡激酶突变体（SakM）对高脂喂养大鼠血液常规的影响。方法选取60只Wistar大鼠,随机分为高脂药物组、高脂生理盐水组、正常药物对照组、正常生理盐水对照组,静脉注射SakM到大鼠体内,剂量按照0．5mg／kg体重,2d注射一次,连续15次,观察SakM对血液常规的影响。结果SakM对正常动物血液常规指标没有影响,但是能够改善高脂喂养动物的血液常规指标结论SakM长期使用不会影响正常动物血液常规指标,具有使用安全性,同时还能用来调节高脂喂养动物的血液常规指标。