口腔粘膜内酶对胰岛素口腔吸收的影响

目的　研究口腔粘膜内酶对胰岛素口腔吸收的影响。方法　用三氯醋酸沉淀法,考察胰岛素在仓鼠口腔粘膜匀浆物中不同条件下的降解情况。在胰岛素口腔喷雾剂中加入酶抑制剂(杆菌肽、屈来赛多)和去氧胆酸钠,考察了大鼠经口腔喷入胰岛素后的血糖降低情况。结果　小肠粘膜细胞内酶活性远高于口腔粘膜细胞中的酶的活性。杆菌肽、屈来赛多和去氧胆酸钠均能抑制口腔粘膜内胰岛素的降解。在相同浓度下,去氧胆酸钠的酶抑制作用比杆菌肽弱,但比屈来赛多强。胰岛素在正常仓鼠口腔内的降解显著大于糖尿病仓鼠。胰岛素溶液中加入杆菌肽、屈来赛多及去氧胆酸钠后,给正常大鼠口腔喷雾给药,药理相对生物利用度分别有不同程度的提高。只含胰岛素的喷雾液(胰岛素空白液) ,喷雾液中加入屈来赛多(0.1% ) ,加入杆菌肽(0.5% ) ,去氧胆酸钠(1% ) ,与sc胰岛素比较药理相对生物利用度分别为2.89% ,4.84% ,7.52 %和9.60%。结论　口腔粘膜中的酶可以限制胰岛素在口腔粘膜的吸收     

不同吸收促进剂对大鼠口腔胰岛素吸收作用的影响

目的 :研究胰岛素的口腔吸收及吸收促进剂、酶抑制剂对药物吸收的影响。方法 :以血糖水平为指标 ,考察各种吸收促进剂和酶抑制剂经糖尿病模型的大鼠口腔给药后对胰岛素溶液 (insulinsolution ,INS SOL)和胰岛素贴片 (insulinpatch ,INS PAT)降血糖作用的影响 ,以皮下注射为对照 ,计算不同条件下INS SOL和INS PAT的药理生物利用度。结果 :不加吸收促进剂的条件下 ,32U·kg-1的INS SOL和10U·kg-1的INS PAT经口腔给药后的生物利用度较低 (0 .77%和 1.82 % )。 3%去氧胆酸钠和 5 %壬苯醇醚均能显著增加INS SOL和INS PAT的降血糖作用 (P <0 .0 5 )。其中 3%去氧胆酸钠作用最明显 ,INS SOL和INS PAT的生物利用度增加了近 3倍(2 .83%和 7.2 6 % )。结论 :胰岛素可通过口腔吸收 ,适当的吸收促进剂对其吸收具有显著的促进作用。     

盐酸丁螺环酮口腔粘附片的制备及释药机理初步研究

口腔粘附制剂是指将药物与适宜的生物粘附剂等辅料经加工制成的制剂 ,使用时将制剂粘附于口腔粘膜上 ,恒定释放药物。口腔粘附制剂不仅能够局部治疗口腔疾病 ,而且药物可以透过口腔粘膜吸收 ,进入血液循环 ,起到全身治疗作用。药物经口腔粘膜吸收时 ,避免了胃肠道及肝脏的首过作用 ,因此对于易受胃肠道酸和酶降解的蛋白质、肽类及其他大分子药物 ,以及受肝脏首过代谢作用严重的药物 ,通过口腔粘膜给药可以提高生物利用度[1] 。本文选择的药物盐酸丁螺环酮 (ｂｕｓｐｉｒｏｎｅｈｙｄｒｏｃｈｌｏｒｉｄｅ)是一个新型的非苯二氮类抗焦虑症…     

粘膜粘附纳米粒在肽类药物给药中的应用

肽类药物生物半衰期短，生物膜渗透性差，且易被胃肠道酶降解，如何提高其生物利用度成为目前药剂学研究的热点之一。近年来兴起研究的粘膜粘附纳米粒可以延长药物在吸收部位的滞留时间而促进药物吸收；某些制备材料还具有酶抑制及膜渗透效应，可防止药物的酶降解及促进药物的跨膜转运，使其成为提高肽类药物生物利用度的新方法。本文综述了粘膜粘附纳米粒常用材料、促进吸收的机制、制备方法及应用方面的进展。     

用氨甲苯酸和没食子酸抗坏血酸液综合治疗口腔粘膜溃疡坏死性病变

材料和方法观察口腔粘膜中度溃疡坏死性病变58例，年龄为16～45岁。其中急性溃疡性龈炎和龈口炎匕例，慢性溃疡性龈炎8例，多形渗出性红斑10例，非特异性口腔粘膜溃疡25例。施行综合治疗，给予维生素C，P，B使用对口腔粘膜无刺激的高热量饮食，按适应证给予脱敏、抗菌、解热和止痛剂，消除局部刺激，保持口腔清洁，用1：500O味哺西林温热液灌洗口腔，用1％美索卡因敷贴或10％利多卡因喷雾止痛，清除溃疡面坏死组织，用氯甲苯酿一没食子酸抗坏血酸（amben－galascorbin）液（l0氨甲苯酸10oml十没食子酸抗坏血酸l～5g）湿敷，l次／d每次15～…     

口腔粘贴缓释膜剂的研究

制成一种可粘贴在口腔粘膜上的缓释膜剂。对各种膜剂的粘膜粘贴力,硝苯啶、硫氮(?)酮从膜剂中的溶出、给药后家兔的血药浓度进行了测定。提出一种药物透粘膜吸收的体外试验方法。口腔粘贴缓释膜剂有较强的粘膜粘贴力,血药浓度维持时间长,生物利用度高。Azone能增加药物的透粘膜极收。     

液氮冷冻治疗小儿口腔粘液囊肿200例体会

粘液囊肿是口腔粘膜常见的类肿瘤。小儿口腔粘液囊肿由于咬舌、咬唇等不良习惯造成粘液腺体损伤，分泌管阻塞，使腺体的粘液储留，腺泡逐渐膨胀形成囊肿。多发于下唇及舌尖腹面粘膜。有些囊肿不规则，手术较困难，极易复发。我科1993年7月～1996年12月采用液氮冷冻法治疗口腔粘液囊肿200例，取得了较满意的疗效，现报告如下。临床资料：200例中，男108例，女92例，年龄5～13岁。位于下唇17o例（占850％），舌尖腹面25例（占12．5％），其它口腔粘膜5例（占2．5％）。冷冻疗法的机理：液氮冷冻主要是通过快速冷却，缓慢融化，使细胞破裂死亡…     

格列美脲口腔崩解片正常人体生物等效性研究

目的研究格列美脲口腔崩解片在正常人体的药代动力学及相对生物利用度。方法20名健康志愿受试者分别单剂量口服格列美脲口腔崩解片（受试制剂）和普通片（参比制剂），用高效液相色谱法测定血药浓度，以3P97计算药动学参数和生物等效性。结果受试制剂或参比制剂体内药时曲线均符合二室模型，峰浓度（Cmax）分别为（406.894-230.57）ng／mL和（409．62±231．58）ng／mL，达峰时间（Tmax）分别为（3.704-1．53）h和（3．58±1．04）h，0～t药时曲线下面积（AUC-t）分别为（3311．60±2038，99）ng·h／mL和（3127，85±1625．64）ng·h／mL．两者药代动力学参数无显著性差异（P〉0．05），受试制荆相对生物利用度为（105．87±12．92）％。结论受试制剂与参比制剂具有生物等效性。     

用中粘度的羟丙基纤维素增加胰岛素的口服吸收

胰岛素口服给药能提高门静脉内的胰岛素水平，这与机体分泌胰岛素的正常生理途径较为相似。而胰岛素其它方案长期给药的同时，必须设法降低外周胰岛素浓度过高引起的伤害。提高口服胰岛素生物利用度的给药方法有加入促渗剂和酶抑制剂等。而载体影响胰岛素口服吸收的作用报道不多，因此通过用不同粘度的辅料方法，力图增加制剂与吸收部位接触时间，以达到增加胰岛素吸收的目的。选用口服后能粘附于粘膜的羟丙基纤维素（HPC）为实验材料，材料按粘度由低到高分别称为GF、MF和HF三种，实验动物为雄性大白兔，并以给药后检测血糖的方法来确…     

黄杨宁口腔速崩片人体药代动力学及相对生物利用度的研究

目的：研究黄杨宁口腔速崩片的人体相对生物利用度和生物等效性。方法：22名健康男性受试者，随机分组双交叉给予黄杨宁口腔速崩片（受试制剂）和黄杨宁片（参比制剂），剂量均为2mg，间隔为2周。分别于给药后120h内多点抽取静脉血，血浆样品经固相萃取（SPE）后用液质联用技术测定其中环维黄杨星D浓度。DAS2．0药动学程序计算相对生物利用度并评价两者的生物等效性。AUC0-120、AUC0-inf和Cmax经方差分析和双单侧t检验，tmax进行秩和检验。结果：单剂量给予受试制剂、参比制剂后血浆中的环维黄杨星D的Cmax分别为（121±55）、（122±52）ng／L；tmax分别为（10±7）、（12±8）h；AUC0-120分别为（4398±1656）、（4524±1760）ng·L^-1·h；AUC0→inf分别为（5292±2034）、（5440±2446）ng·L^-1·h。Cmax的90％可信区间为82．7％～117．3％；AUC－120的90％可信区间为83．9％。112．9％；AUC0→inf的90％可信区间为83．4％～117．6％。结论：受试制剂的人体相对生物利用度为（97．7±14．7）％，与参比制剂相比，两者具有生物等效性。     

Absorption Enhancement of Intranasally Administered Insulin by Sodium Taurodihydrofusidate (STDHF) in Rabbits and Rats

The enhancement of nasal insulin absorption by sodium taurodihydrofusidate (STDHF) was studied in rabbits and rats. Using identical nasal formulations remarkable interspecies differences were observed. The fusidate derivative at 1% (w/v) enhanced nasal insulin bioavailability from 0.9 to 5.2% and from 0.3 to 18.0% in rabbits and rats, respectively. In both species the insulin formulations with STDHF resulted in strong hypoglycemic responses. Coadministration with the trypsin inhibitor aprotinin tended further to increase insulin bioavailability in rats and decrease insulin bioavailability in rabbits; however, these aprotinin effects were not statistically significant. Addition of the aminopeptidase inhibitor bacitracin to the STDHF containing formulation did not have any effect on insulin bioavailability in rats. Hence, STDHF is a potent enhancer of nasal insulin absorption, probably both by facilitating insulin transport through the nasal mucosa and possibly also by inhibiting enzymatic degradation. Further, interspecies differences and, experimental animal conditions can greatly affect nasal drug absorption.     

Proteolytic enzymes as a limitation for pulmonary absorption of insulin: in vitro and in vivo investigations

In vitro biodegradation of insulin in lung cytosol and subcellular pellets of normal and diabetic rats was investigated. Rat lung was homogenized and subcellular fractions were isolated by ultracentrifugation. Degradations of [125I]-insulin after incubation with lung cytosol or subcellular pellets was determined using the trichloroacetic acid method. The results show that insulin is highly degraded in cytosol and subcellular pellets. Cytosolic insulin degradation was strongly inhibited by bacitracin or sodium cholate. The degradation of insulin in the lung cytosol from diabetic rats was significantly less than from normal rat. The lung protease activity reached a maximum at pH 7.4. Enzyme inhibitors like bacitracin and sodium cholate noticeably enhanced the relative pharmacological bioavailability of insulin when given intratracheally with insulin to normal rats. Acidic insulin solutions (pH 3.0) had more pronounced hypoglycaemic effects than neutrol solution (pH 7.0). These in vitro and in vivo results suggest that the proteolytic enzymes in the lung limit pulmonary delivery of insulin. The coadministration of protease inhibitors would be a useful approach for improving the pulmonary absorption of insulin.     

Use of Protease Inhibitors to Improve Calcitonin Absorption from the Small and Large Intestine in Rats

The objective of this study was to examine the effects of protease inhibitors on the absorption of calcitonin from different regions of the intestine in rats. The absorption experiments were investigated by in-situ use of closed intestinal loops in rats and stability of calcitonin was examined in mucosal homogenates and intestinal fluids. The intestinal absorption of calcitonin was evaluated by measurement of its hypocalcaemic effect. No substantial hypocalcaemic response was observed when calcitonin was administered into the jejunum or colon. A slight hypocalcaemic effect was observed after administration of calcitonin into the ileum. Of the co-administered protease inhibitors, bacitracin (20 mM) strongly promoted calcitonin absorption from the jejunum, ileum and colon. A significant hypocalcaemic effect was also obtained after intestinal administration of calcitonin with soybean trypsin inhibitor (10mgmL^?1), camostat mesylate (20mM) or aprotinin (2mgmL^?1). In the stability experiment, bacitracin reduced the degradation of calcitonin in the different intestinal homogenates. Soybean trypsin inhibitor significantly reduced the degradation of calcitonin in the fluids of the small intestine. We also examined the different endopeptidases in gut luminal fluids and the different exopeptidases in gut mucosal homogenates of rats. The ranking order for the total endopeptidase activity of the intestinal fluids was jejunum > ileum > colon. That for total exopeptidase activity of the intestinal mucosa was jejunum > ileum > colon. These results suggest that endo- and exopeptidases might be responsible for the hydrolysis of calcitonin and that protease inhibitors might usefully improve absorption of calcitonin to the systemic circulation from the large intestine.     

Buccal delivery of thiocolchicoside: in vitro and in vivo permeation studies

Thiocolchicoside, a muscle-relaxant agent, is administered by the oral, intra-muscular and topical route. After oral administration the extent of bioavailability compared with intra-muscular administration is low, due to a first pass effect. In this paper, the delivery of thiocolchicoside through oral mucosa is studied to improve the bioavailability. Thiocolchicoside in vitro permeation through porcine oral mucosa and in vivo buccal transport in humans were investigated. Two dosage forms, a bioadhesive disc and a fast dissolving disc for buccal and sublingual administration of thiocolchicoside, respectively, were designed. The in vitro permeation of thiocolchicoside through porcine buccal mucosa from these dosage forms was evaluated and compared with in vivo absorption. Results from in vitro studies demonstrated that thiocolchicoside is quite permeable across porcine buccal mucosa and that permeation enhancers, such as sodium taurocholate and sodium taurodeoxycholate, were not able to increase its flux. The in vivo thiocolchicoside absorption experiments, in which the drug loss from oral cavity was measured, indicated that both formulations could be useful for therapeutic application. The fast dissolving (sublingual) form resulted in a quick uptake of 0.5 mg of thiocolchicoside within 15 min whereas with the adhesive buccal form the same dose can be absorbed over an extended period of time.     

Effects of Various Protease Inhibitors on the Intestinal Absorption and Degradation of Insulin in Rats

The effects of protease inhibitors on the intestinal absorption of insulin were investigated in situ in closed small and large intestinal loops in rats, and the stability of insulin was examined in homoge-nates of the small and large intestine. The intestinal absorption of insulin was evaluated by its hypoglycemic effect. When insulin alone was administered into small or large intestinal loops, no marked hypoglycemic response was observed in either region. Of the coadministered protease inhibitors, soybean trypsin inhibitor (1.5, 10 mg/ml) marginally promoted insulin absorption from the large intestine, whereas aprotinin (10 mg/ml) did to a moderate degree. However, a significant hypoglycemic effect was obtained following large intestinal administration of insulin with 20 mM of Na-glycocholate, camostat mesilate and bacitracin, when compared with the controls. In contrast, we found little hypoglycemic effect following small intestinal coadministration of insulin with these protease inhibitors. In the stability experiment, bacitracin, camostat mesilate and Na-glycocholate were effective in reducing insulin degradation in both small and large intestinal homogenates. It was found that the reduction in the proteolytic rate of insulin was related to the decrease in plasma glucose concentration by these protease inhibitors in the large intestine. These findings suggest that coadministration of protease inhibitors would be useful for improving the large intestinal absorption of insulin.     

Buccal mucosal ulcer healing effect of rhEGF/Eudispert hv hydrogel

We have studied the effect of rhEGF on the buccal mucosal ulcer healing. rhEGF was rapidly degraded upon incubation with the hamster buccal mucosal homogenates; The degradation of rhEGF was significantly inhibited by sodium lauryl sulfate (SLS). Eudispert hv hydrogel and Polycarbophil 974P hydrogel were prepared for rhEGF delivery and their mucoadhesiveness was measured by the Instron method. The mucoadhesive force of Eudispert hv was significantly greater than that of Polycarbophil 974P. Moreover, rhEGF in Eudispert hv hydrogel remained stable for about 2 months. To evaluate the ulcer healing effect of rhEGF, the buccal mucosal ulcer was induced in golden hamsters using acetic acid. At 24 h after administration of rhEGF/Eudispert hv hydrogel, the ulcerous area was decreased compared with rhEGF solution and, as a result, the curative ratio was 36.8 +/- 5.68%. By the addition of SLS (0.5%) to Eudispert hv hydrogel, the curative ratio increased 1.5 times. The mechanism of the action was probably due to a combination of protection of the drug against proteases present in mucosa and prolongation of the release of rhEGF from the formulation at the site of action.     

胰岛素经口腔给药对正常大鼠的降血糖作用

目的　研究胰岛素溶液 (insulinsolution ,INS SOL)经正常大鼠口腔给药后的降血糖作用。方法　以血糖水平为指标 ,考察各种吸收促进剂经正常大鼠口腔给药后对INS SOL降血糖作用的影响 ,以皮下注射为对照 ,计算不同条件下INS SOL的药理生物利用度 (pharmacologicalbioavailability ,PA)。 结果　不加吸收促进剂的条件下 ,10U·kg-1的INS SOL经口腔给药后的生物利用较低 (PA =6 9% )。十二烷基硫酸钠 (5 % ,PA =14 5 % ) ,苄泽 78(5 % ,PA =2 0 6 % ) ,脱氧胆酸钠 (5 % ,PA =16 5 % )和卵磷脂(10 % ,PA =13 8% )均增加INS SOL的降血糖作用。苄泽78(5 % )可使INS SOL(5U·kg-1)的PA最高达到 33%。结论　在适当的吸收促进剂的作用下INS SOL经口腔给药后具有明显的降血糖效果。