循环饥饿投喂对大鼠消化道嗜银细胞 形态及分布的影响

为了研究循环饥饿投喂对大鼠(Rattus norvegicus)消化道内嗜银细胞的分布密度及形态功能的影响,本实验采用Grimelius银染法观察和测定循环饥饿投喂(饥饿1 d,投喂1 d,周期为14 d)期间大鼠消化道嗜银细胞形态功能及密度分布。结果表明,实验组(即循环饥饿投喂组)和对照组(正常喂食组)大鼠消化道嗜银细胞除食管外均有分布,形态上对照组嗜银细胞以椭圆形和锥体形为主,实验组嗜银细胞则主要以锥体形为主;两组大鼠消化道嗜银细胞的分布密度高峰都位于胃,密度低谷对照组位于空肠、盲肠、回肠和直肠,实验组位于空肠到直肠各段;实验组大鼠消化道嗜银细胞分布密度在贲门和幽门部极显著低于对照组(P 0.01),结肠显著低于对照组(P 0.05),说明循环饥饿投喂会明显改变消化道嗜银细胞的形态并降低细胞数量,这可能与内分泌细胞的功能改变有关。     

牛蛙冬眠期及其前后的消化道嗜银细胞分布

为研究两栖类在冬眠期及其前后消化道嗜银细胞是否参与冬眠期的消化调节,本文以牛蛙(Rana catesbeiana)为实验对象,采用Grimelius银染法,对冬眠期前(n = 10)、冬眠期(n = 10)和冬眠期后(n = 10)牛蛙消化道嗜银细胞的形态及密度进行比较研究。结果表明,牛蛙消化道各部位均有嗜银细胞分布;牛蛙消化道嗜银细胞形态在冬眠期、冬眠期前及冬眠期后无差异,均为锥体型、梭型和椭圆型;牛蛙消化道各部位具有外分泌功能的锥体型和梭形嗜银细胞密度在3个时期均显著高于具有内分泌功能的椭圆型嗜银细胞密度(P < 0.01);3个时期牛蛙消化道嗜银细胞分布密度高峰均位于空肠处,但低谷有所不同,冬眠期前和冬眠期后牛蛙消化道嗜银细胞的分布密度低谷位于食管,而冬眠期其分布密度低谷位于贲门;3个时期相比,冬眠期前和冬眠期幽门处分布密度差异不显著(P > 0.05),其余部位均有差异,且食管、胃、十二指肠、空肠、回肠和直肠中嗜银细胞分布密度在冬眠期显著高于冬眠期前和冬眠期后(P < 0.05);冬眠期前和冬眠期后消化道嗜银细胞分布密度呈倒“U”型趋势,冬眠期分布密度呈现“~”型趋势。结合相关研究,推测牛蛙嗜银细胞分布密度的改变可能与机体适应不同生理状态及消化功能的调节有关。     

花背蟾蜍消化道嗜银细胞形态和分布密度的增龄变化

目的比较幼体、亚成体和成体花背蟾蜍(Pseudepidalea raddei)消化道嗜银细胞的形态学特点和分布密度的增龄变化。方法取不同年龄组花背蟾蜍的食管、贲门、胃底、幽门、十二指肠、空肠、回肠和直肠等部位,用Grimelius银染法结合微波技术对各段的嗜银细胞进行染色。结果消化道嗜银细胞分为闭合型和开放型细胞两种类型,从食管至直肠的形态学特征无明显的增龄变化。幼蟾食管嗜银细胞的分布密度显著高于贲门和空肠;亚成体蟾和成蟾都在食管最高,直肠最低,但无显著的部位差异。成蟾和亚成体蟾贲门、胃底和空肠嗜银细胞的分布密度都显著高于幼蟾,成蟾回肠与亚成体蟾接近,但高于幼蟾,食管、幽门和直肠未见年龄差异。结论花背蟾蜍消化道嗜银细胞的形态学特征不随年龄而改变,但分布密度在贲门、胃底、空肠和回肠等部位表现出明显的增龄变化,这可能与食物的机械消化作用和吸收营养物质的能力随年龄而逐渐加强有关。     

猫儿山两种有尾两栖类消化道嗜银细胞比较观察

为探究有尾两栖类消化道内分泌细胞的特点,以分布于猫儿山保护区的猫儿山小鲵（Hynobius maoershanensis）和瑶山肥螈（Pachytriton inexpectatus）为研究对象,采用Grimelius银染法,对二者消化道嗜银细胞的形态特征、分布区域与分布密度进行了比较研究,为有尾两栖类消化道比较组织学和内分泌学研究积累基础资料,并为两栖类消化生理学研究提供形态学数据基础。结果显示,两种动物从食道至直肠均有嗜银细胞分布,分布型都呈波浪形,均在食道处分布密度（个/视野）最高,猫儿山小鲵为2.00 ± 0.69,瑶山肥螈为3.42 ± 0.31,在猫儿山小鲵回肠（1.45 ± 0.50）和瑶山肥螈在直肠（1.63 ± 0.97）分布密度最低。瑶山肥螈消化道各部位嗜银细胞的分布密度都高于猫儿山小鲵,两种动物嗜银细胞分布密度在食道、贲门、十二指肠和回肠中差异显著,但在胃体、幽门和直肠中差异不显著。对同一物种消化道不同部位嗜银细胞进行比较,猫儿山小鲵及瑶山肥螈的嗜银细胞分布密度高峰均出现在食道,其中,猫儿山小鲵食道与十二指肠、回肠、直肠差异显著（P < 0.05）,瑶山肥螈食道与其他各部位差异显著（P < 0.05）。嗜银细胞形状多样,有圆形、椭圆形、锥形和梭形等,可分为闭合型和开放型细胞。猫儿山小鲵生活环境多为沼泽地,富含淤泥、落叶,喜食蛙类蝌蚪、蚯蚓等个体较小且易消化的食物,瑶山肥螈生活环境为石块粗砂较多的山溪,以虾、蟹、螺等为食,这两种动物消化道嗜银细胞的形态特征和分布密度各具自身特点,可能与其生境及食性等因素有关。     

中华大蟾蜍消化道嗜银细胞的分布及形态学观察

本文用Grimelius嗜银法对12只中华大蟾蜍消化道嗜银细胞的分布及形态进行了初步观察．结果显示：（1）中华大蟾蜍消化道嗜银细胞的分布密度依次为;食管为31．51±6.73;胃贲门为67．52±3．81;胃体部为49．41±5．69;胃幽门部为142．58±6．69;十二指肠为34．63±5．26;空肠为25．36±2．57;回肠为13．28±3．29;（2）嗜银细胞在食管部分主要集中子食管腺;在胃部主要集中于胃腺,在小肠部主要分布于绒毛上皮之间;（3）嗜银细胞的形态也是多种多样,有锥体形、三角形、椭圆形、长梭形等。     

蛇岛蝮蛇消化道嗜银细胞的分布及形态学观察

应用Grimelius银染法对蛇岛蝮蛇Gloydius shedaoensis 消化道嗜银细胞的分布密度及形态进行研究.结果 表明,蛇岛蝮蛇的消化道中嗜银细胞分布广泛,见于其全长,主要分布于上皮细胞基部、上皮细胞之间、腺泡上皮细胞之间,也有少量位于固有膜内;胃贲门是嗜银细胞分布密度的高峰,胃体次之,食管分布密度最低;嗜银细胞形态多样,主要有锥体形、梭形、圆形和椭圆形,具有内、外分泌两种功能.     

褐家鼠消化道嗜银细胞的分布及形态学观察

应用Grimelius银染法观察了褐家鼠Arattus norvegicus消化道嗜银细胞的分布密度及形态.结果 显示,在褐家鼠的消化道除食管未见嗜银细胞外,其它部位均有嗜银细胞的分布,其分布密度为胃贲门部最高,回肠部最低.嗜银细胞多分布于消化道粘膜上皮细胞之间或腺泡上皮之间,有时可见于上皮基部和固有膜内.嗜银细胞形态多样,主要以锥体形为主,其次还有圆形、梭形和椭圆形.根据其嗜银细胞形态,认为褐家鼠消化道内嗜银细胞具有内、外分泌、旁分泌3种功能.     

东亚腹链蛇消化道嗜银细胞的分布及形态学观察

应用Grimelius银染法研究了东亚腹链蛇（Amphiesma vibakari）消化道嗜银细胞的分布密度及形态。结果表明：在东亚腹链蛇的消化道中嗜银细胞分布广泛,见于全消化道。其分布密度曲线大致呈波浪形,其中胃部是嗜银细胞分布密度的高峰,胃幽门次之,回肠分布密度最低。嗜银细胞形态多样,主要以锥体形为主,其次还有圆形、椭圆形。广泛分布于上皮细胞基部、上皮细胞之间、腺泡上皮细胞之间。结论：东亚腹链蛇消化道嗜银细胞分布型的形成与各部位消化功能有关;根据其形态,我们认为东亚腹链蛇消化道内嗜银细胞具有内分泌、外分泌、旁分泌3种功能。     

禁食对东方蝾螈胃肠道嗜银细胞形态 和分布密度的影响

以改良的龙桂开浸银法,比较了喂食和禁食15 d后的东方蝾螈(Cynops orientalis)胃肠道的长度与重量、嗜银细胞的形态及分布密度的变化。结果表明,禁食后动物的肠鲜重下降,胃长度缩短。禁食处理对嗜银细胞的形态无明显影响,呈圆形、椭圆形、楔形、锥体形、毛笔头状和蝌蚪形等。喂食组的分布密度高峰为幽门,低谷为十二指肠;禁食组的分布密度高峰为贲门,低谷为十二指肠、回肠和直肠。除幽门和十二指肠外,禁食组其余胃肠道各部位的密度都高于喂食组。禁食使东方蝾螈胃肠道前、后端嗜银细胞的密度增加,这可能与东方蝾螈的摄食习性和能较长时间耐受饥饿的生理特性有关。     

小鼠胃肠道嗜银细胞的分布及形态学观察

用Grimelius嗜银法对10只小鼠胃肠道嗜银细胞的分布及形态学作了观察研究,结果显示：（l）小鼠嗜银细胞的分布密度,在胃体部最高,从十二脂肠、空肠、回肠、盲肠直到结肠依次减少。（2）嗜银细胞的形态也是多种多样,有梭形、锥体形、椭圆形等。     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices     

Characterization of the composition of the aqueous humor and the vitreous body of the eye of the frog Rana temporaria L

This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10^− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.     

Observations on the permeability of the choriocapillaris of the eye

Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418